Patient Care

Clinical question: What risk factors could predict the likelihood of Pseudomonas and methicillin-resistant Staphylococcus aureus (MRSA) in patients hospitalized with healthcare-associated pneumonia (HCAP)?

Background: Patients identified with HCAP have an increased risk for multi-drug-resistant pathogens, such as gram-negative (GNR) organisms and MRSA. Meeting criteria for HCAP does not discriminate between the different infections, which require different antibiotic classes for treatment. Risk factors need to be identified to determine the most likely infectious organism to help guide initial empiric antibiotic therapy.

Study design: Retrospective cohort study.

Setting: Veterans Affairs hospitals.

Synopsis: Of 61,651 veterans with HCAP diagnosis, 1,156 (1.9%) had a discharge diagnosis of Pseudomonas pneumonia and were found to be younger and more likely to be immunocompromised; have hemiplegia; have a history of chronic obstructive pulmonary disease; have had corticosteroid exposure; and have been exposed to a fluoroquinolone, β-lactam, cephalosporin, or carbapenem antiobiotic within 90 days prior to admission. Pseudomonas pneumonia was negatively associated with age >84, drug abuse, diabetes, and higher socioeconomic status. A discharge diagnosis of MRSA pneumonia was found in 641 patients (1.0%), who also were positively associated with the male gender, age >74, recent nursing home stay, and recent exposure to fluoroquinolone antibiotics within 90 days prior to admission.

MRSA pneumonia was negatively associated with complicated diabetes. Neither diagnosis was present in 59,854 patients (97.1%).

This study was limited due to its predominantly male veteran population, low incidence of Pseudomonas and MRSA pneumonia being identified, and Pseudomonas as the only GNR organism analyzed.

Bottom line: Risk factors identified for Pseudomonas and MRSA pneumonia can help guide targeted antibiotics for HCAP patients.

Citation: Metersky ML, Frei CR, Mortenson EM. Predictors of Pseudomonas and methicillin-resistant Staphylococcus aureus in hospitalized patients with healthcare-associated pneumonia. Respirology. 2016;21(1):157-163.

Short Take

Hematuria as Marker of Urologic Cancer

Narrative literature review did not demonstrate beneficial role of screening urinalysis for cancer detection in asymptomatic patients, but it did suggest including gross hematuria as part of routine review of systems.

Citation: Nielsen M, Qaseem A, High Value Care Task Force of the American College of Physicians. Hematuria as a marker of occult urinary tract cancer: advice for high-value care from the American College of Physicians. Ann Intern Med. 2016;164(7):488-497. doi:10.7326/M15-1496.

Clinical question: What risk factors could predict the likelihood of Pseudomonas and methicillin-resistant Staphylococcus aureus (MRSA) in patients hospitalized with healthcare-associated pneumonia (HCAP)?

Background: Patients identified with HCAP have an increased risk for multi-drug-resistant pathogens, such as gram-negative (GNR) organisms and MRSA. Meeting criteria for HCAP does not discriminate between the different infections, which require different antibiotic classes for treatment. Risk factors need to be identified to determine the most likely infectious organism to help guide initial empiric antibiotic therapy.

Study design: Retrospective cohort study.

Setting: Veterans Affairs hospitals.

Synopsis: Of 61,651 veterans with HCAP diagnosis, 1,156 (1.9%) had a discharge diagnosis of Pseudomonas pneumonia and were found to be younger and more likely to be immunocompromised; have hemiplegia; have a history of chronic obstructive pulmonary disease; have had corticosteroid exposure; and have been exposed to a fluoroquinolone, β-lactam, cephalosporin, or carbapenem antiobiotic within 90 days prior to admission. Pseudomonas pneumonia was negatively associated with age >84, drug abuse, diabetes, and higher socioeconomic status. A discharge diagnosis of MRSA pneumonia was found in 641 patients (1.0%), who also were positively associated with the male gender, age >74, recent nursing home stay, and recent exposure to fluoroquinolone antibiotics within 90 days prior to admission.

MRSA pneumonia was negatively associated with complicated diabetes. Neither diagnosis was present in 59,854 patients (97.1%).

This study was limited due to its predominantly male veteran population, low incidence of Pseudomonas and MRSA pneumonia being identified, and Pseudomonas as the only GNR organism analyzed.

Bottom line: Risk factors identified for Pseudomonas and MRSA pneumonia can help guide targeted antibiotics for HCAP patients.

Citation: Metersky ML, Frei CR, Mortenson EM. Predictors of Pseudomonas and methicillin-resistant Staphylococcus aureus in hospitalized patients with healthcare-associated pneumonia. Respirology. 2016;21(1):157-163.

Short Take

Hematuria as Marker of Urologic Cancer

Narrative literature review did not demonstrate beneficial role of screening urinalysis for cancer detection in asymptomatic patients, but it did suggest including gross hematuria as part of routine review of systems.

Citation: Nielsen M, Qaseem A, High Value Care Task Force of the American College of Physicians. Hematuria as a marker of occult urinary tract cancer: advice for high-value care from the American College of Physicians. Ann Intern Med. 2016;164(7):488-497. doi:10.7326/M15-1496.

Clinical question: What risk factors could predict the likelihood of Pseudomonas and methicillin-resistant Staphylococcus aureus (MRSA) in patients hospitalized with healthcare-associated pneumonia (HCAP)?

Background: Patients identified with HCAP have an increased risk for multi-drug-resistant pathogens, such as gram-negative (GNR) organisms and MRSA. Meeting criteria for HCAP does not discriminate between the different infections, which require different antibiotic classes for treatment. Risk factors need to be identified to determine the most likely infectious organism to help guide initial empiric antibiotic therapy.

Study design: Retrospective cohort study.

Setting: Veterans Affairs hospitals.

Synopsis: Of 61,651 veterans with HCAP diagnosis, 1,156 (1.9%) had a discharge diagnosis of Pseudomonas pneumonia and were found to be younger and more likely to be immunocompromised; have hemiplegia; have a history of chronic obstructive pulmonary disease; have had corticosteroid exposure; and have been exposed to a fluoroquinolone, β-lactam, cephalosporin, or carbapenem antiobiotic within 90 days prior to admission. Pseudomonas pneumonia was negatively associated with age >84, drug abuse, diabetes, and higher socioeconomic status. A discharge diagnosis of MRSA pneumonia was found in 641 patients (1.0%), who also were positively associated with the male gender, age >74, recent nursing home stay, and recent exposure to fluoroquinolone antibiotics within 90 days prior to admission.

MRSA pneumonia was negatively associated with complicated diabetes. Neither diagnosis was present in 59,854 patients (97.1%).

This study was limited due to its predominantly male veteran population, low incidence of Pseudomonas and MRSA pneumonia being identified, and Pseudomonas as the only GNR organism analyzed.

Bottom line: Risk factors identified for Pseudomonas and MRSA pneumonia can help guide targeted antibiotics for HCAP patients.

Citation: Metersky ML, Frei CR, Mortenson EM. Predictors of Pseudomonas and methicillin-resistant Staphylococcus aureus in hospitalized patients with healthcare-associated pneumonia. Respirology. 2016;21(1):157-163.

Short Take

Hematuria as Marker of Urologic Cancer

Narrative literature review did not demonstrate beneficial role of screening urinalysis for cancer detection in asymptomatic patients, but it did suggest including gross hematuria as part of routine review of systems.

Citation: Nielsen M, Qaseem A, High Value Care Task Force of the American College of Physicians. Hematuria as a marker of occult urinary tract cancer: advice for high-value care from the American College of Physicians. Ann Intern Med. 2016;164(7):488-497. doi:10.7326/M15-1496.

Clinical question: What are the current recommendations for antithrombotic therapy in various venous thromboembolism (VTE) scenarios?

Background: VTE is commonly encountered with a multitude of therapeutic options. Selecting the optimal anticoagulant is as important as making the diagnosis and requires knowledge of individual patient characteristics to initiate the correct therapy. These factors include malignancy, location of thrombus, and history of recurrent VTE despite anticoagulation.

Study design: Guideline.

Setting: Expert panel.

Synopsis: For VTE patients without cancer, non-vitamin K oral anticoagulants (NOAC) are now suggested over vitamin K antagonists (Grade 2B). However, there remains no strong evidence to favor one NOAC over another.

Better evidence now supports the prior recommendation to discourage IVC filters for VTE that is being treated with anticoagulation (Grade 1B).

In pulmonary embolism of the subsegmental type without proximal DVT, clinical surveillance is favored over anticoagulation in lower-risk patients (Grade 2C).

Low-molecular-weight heparin (LMWH) is advised in recurrent VTE treated with non-LMWH, and for recurrences on LMWH, a dose increase of LMWH is advised (Grade 2C).

Finally, routine use of compression stockings for post-thrombotic syndrome prevention is not routinely recommended (Grade 2B).

Limitations include only 20 of the 54 total recommendations being of strong Grade 1 criteria. Additionally, none of the 54 statements are drawn from high-quality evidence.

Further study is needed to continually update our practice in caring for VTE disease as more experience and comparison data are obtained with the use of NOAC drugs.

Bottom line: Anticoagulant therapy recommendations have been updated, but few are strong recommendations and none are based on high-quality evidence.

Citation: Kearon C, Akl EA, Ornelas J, et al. Antithrombotic therapy for VTE disease: CHEST guideline and expert panel report. Chest. 2016;149(2):315-352.

Clinical question: What are the current recommendations for antithrombotic therapy in various venous thromboembolism (VTE) scenarios?

Background: VTE is commonly encountered with a multitude of therapeutic options. Selecting the optimal anticoagulant is as important as making the diagnosis and requires knowledge of individual patient characteristics to initiate the correct therapy. These factors include malignancy, location of thrombus, and history of recurrent VTE despite anticoagulation.

Study design: Guideline.

Setting: Expert panel.

Synopsis: For VTE patients without cancer, non-vitamin K oral anticoagulants (NOAC) are now suggested over vitamin K antagonists (Grade 2B). However, there remains no strong evidence to favor one NOAC over another.

Better evidence now supports the prior recommendation to discourage IVC filters for VTE that is being treated with anticoagulation (Grade 1B).

In pulmonary embolism of the subsegmental type without proximal DVT, clinical surveillance is favored over anticoagulation in lower-risk patients (Grade 2C).

Low-molecular-weight heparin (LMWH) is advised in recurrent VTE treated with non-LMWH, and for recurrences on LMWH, a dose increase of LMWH is advised (Grade 2C).

Finally, routine use of compression stockings for post-thrombotic syndrome prevention is not routinely recommended (Grade 2B).

Limitations include only 20 of the 54 total recommendations being of strong Grade 1 criteria. Additionally, none of the 54 statements are drawn from high-quality evidence.

Further study is needed to continually update our practice in caring for VTE disease as more experience and comparison data are obtained with the use of NOAC drugs.

Bottom line: Anticoagulant therapy recommendations have been updated, but few are strong recommendations and none are based on high-quality evidence.

Citation: Kearon C, Akl EA, Ornelas J, et al. Antithrombotic therapy for VTE disease: CHEST guideline and expert panel report. Chest. 2016;149(2):315-352.

Clinical question: What are the current recommendations for antithrombotic therapy in various venous thromboembolism (VTE) scenarios?

Background: VTE is commonly encountered with a multitude of therapeutic options. Selecting the optimal anticoagulant is as important as making the diagnosis and requires knowledge of individual patient characteristics to initiate the correct therapy. These factors include malignancy, location of thrombus, and history of recurrent VTE despite anticoagulation.

Study design: Guideline.

Setting: Expert panel.

Synopsis: For VTE patients without cancer, non-vitamin K oral anticoagulants (NOAC) are now suggested over vitamin K antagonists (Grade 2B). However, there remains no strong evidence to favor one NOAC over another.

Better evidence now supports the prior recommendation to discourage IVC filters for VTE that is being treated with anticoagulation (Grade 1B).

In pulmonary embolism of the subsegmental type without proximal DVT, clinical surveillance is favored over anticoagulation in lower-risk patients (Grade 2C).

Low-molecular-weight heparin (LMWH) is advised in recurrent VTE treated with non-LMWH, and for recurrences on LMWH, a dose increase of LMWH is advised (Grade 2C).

Finally, routine use of compression stockings for post-thrombotic syndrome prevention is not routinely recommended (Grade 2B).

Limitations include only 20 of the 54 total recommendations being of strong Grade 1 criteria. Additionally, none of the 54 statements are drawn from high-quality evidence.

Further study is needed to continually update our practice in caring for VTE disease as more experience and comparison data are obtained with the use of NOAC drugs.

Bottom line: Anticoagulant therapy recommendations have been updated, but few are strong recommendations and none are based on high-quality evidence.

Citation: Kearon C, Akl EA, Ornelas J, et al. Antithrombotic therapy for VTE disease: CHEST guideline and expert panel report. Chest. 2016;149(2):315-352.

Clinical question: Is tamsulosin efficacious as an expulsive therapy for distal ureter stones ≤10 mm in diameter?

Background: Ureteric calculi are a common reason for hospital admission, and use of medical expulsive therapy during observation periods for small caliber stones has gained much attention recently. Specifically, tamsulosin has been suggested as a medical therapy for small stones.

Study design: Randomized, double-blind, placebo-controlled study.

Setting: Five EDs in Australia.

Synopsis: A total of 403 patients participated in the study, based on inclusion criteria of age older than 18 years with symptoms and CT evidence of ureteric stones Exclusion criteria included fever, glomerular filtration rate <60, and calculi >10 mm. Patients were randomized to placebo or 0.4 mg tamsulosin daily for 28 days. The outcome was stone expulsion demonstrated by absence of calculi on repeat CT. Stone passage in the entire group occurred in 87% of the tamsulosin arm and 81.9% of the placebo, with a 95% CI of -3.0% to 13%, which was not a significant difference with P=0.22.

Interestingly, in a subgroup analysis of larger stones 5–10 mm, 83% of tamsulosin subjects compared to 61% of placebo subjects had stone passage that was significant at a 22% difference and P=.03.

Limitations included compliance in both groups, applicability to other populations given study based in Australia, and the lack of follow-through with CT scan at 28 days in 17% of the original group, resulting in missing outcome data.

Bottom line: Patients with ureteric stones 5–10 mm in size demonstrate increased spontaneous stone expulsion with the addition of tamsulosin and should thus be offered this therapy.

Citation: Furyk J, Chu K, Banks C, et al. Distal ureteric stones and tamsulosin: a double-blind, placebo-controlled, randomized, multicenter trial. Ann Emerg Med. 2016;67(1):86-95.e2.

Short Take

Low Diagnostic Yield of Blood Cultures in Hospitalized Medical Patients

Prospective cohort study of patients hospitalized on a medical service demonstrated a true positive rate of blood cultures that was lower than previously studied. Using objective clinical predictors may improve likelihood of true positive blood cultures.

Citation: Linsenmeyer K, Gupta K, Strymish JM, Dhanani M, Brecher SM, Breu AC. Culture if spikes? Indications and yield of blood cultures in hospitalized medical patients [published online ahead of print January 13, 2016]. J Hosp Med. doi:10.1002/jhm.2541.

Clinical question: Is tamsulosin efficacious as an expulsive therapy for distal ureter stones ≤10 mm in diameter?

Background: Ureteric calculi are a common reason for hospital admission, and use of medical expulsive therapy during observation periods for small caliber stones has gained much attention recently. Specifically, tamsulosin has been suggested as a medical therapy for small stones.

Study design: Randomized, double-blind, placebo-controlled study.

Setting: Five EDs in Australia.

Synopsis: A total of 403 patients participated in the study, based on inclusion criteria of age older than 18 years with symptoms and CT evidence of ureteric stones Exclusion criteria included fever, glomerular filtration rate <60, and calculi >10 mm. Patients were randomized to placebo or 0.4 mg tamsulosin daily for 28 days. The outcome was stone expulsion demonstrated by absence of calculi on repeat CT. Stone passage in the entire group occurred in 87% of the tamsulosin arm and 81.9% of the placebo, with a 95% CI of -3.0% to 13%, which was not a significant difference with P=0.22.

Interestingly, in a subgroup analysis of larger stones 5–10 mm, 83% of tamsulosin subjects compared to 61% of placebo subjects had stone passage that was significant at a 22% difference and P=.03.

Limitations included compliance in both groups, applicability to other populations given study based in Australia, and the lack of follow-through with CT scan at 28 days in 17% of the original group, resulting in missing outcome data.

Bottom line: Patients with ureteric stones 5–10 mm in size demonstrate increased spontaneous stone expulsion with the addition of tamsulosin and should thus be offered this therapy.

Citation: Furyk J, Chu K, Banks C, et al. Distal ureteric stones and tamsulosin: a double-blind, placebo-controlled, randomized, multicenter trial. Ann Emerg Med. 2016;67(1):86-95.e2.

Short Take

Low Diagnostic Yield of Blood Cultures in Hospitalized Medical Patients

Prospective cohort study of patients hospitalized on a medical service demonstrated a true positive rate of blood cultures that was lower than previously studied. Using objective clinical predictors may improve likelihood of true positive blood cultures.

Citation: Linsenmeyer K, Gupta K, Strymish JM, Dhanani M, Brecher SM, Breu AC. Culture if spikes? Indications and yield of blood cultures in hospitalized medical patients [published online ahead of print January 13, 2016]. J Hosp Med. doi:10.1002/jhm.2541.

Clinical question: Is tamsulosin efficacious as an expulsive therapy for distal ureter stones ≤10 mm in diameter?

Background: Ureteric calculi are a common reason for hospital admission, and use of medical expulsive therapy during observation periods for small caliber stones has gained much attention recently. Specifically, tamsulosin has been suggested as a medical therapy for small stones.

Study design: Randomized, double-blind, placebo-controlled study.

Setting: Five EDs in Australia.

Synopsis: A total of 403 patients participated in the study, based on inclusion criteria of age older than 18 years with symptoms and CT evidence of ureteric stones Exclusion criteria included fever, glomerular filtration rate <60, and calculi >10 mm. Patients were randomized to placebo or 0.4 mg tamsulosin daily for 28 days. The outcome was stone expulsion demonstrated by absence of calculi on repeat CT. Stone passage in the entire group occurred in 87% of the tamsulosin arm and 81.9% of the placebo, with a 95% CI of -3.0% to 13%, which was not a significant difference with P=0.22.

Interestingly, in a subgroup analysis of larger stones 5–10 mm, 83% of tamsulosin subjects compared to 61% of placebo subjects had stone passage that was significant at a 22% difference and P=.03.

Limitations included compliance in both groups, applicability to other populations given study based in Australia, and the lack of follow-through with CT scan at 28 days in 17% of the original group, resulting in missing outcome data.

Bottom line: Patients with ureteric stones 5–10 mm in size demonstrate increased spontaneous stone expulsion with the addition of tamsulosin and should thus be offered this therapy.

Citation: Furyk J, Chu K, Banks C, et al. Distal ureteric stones and tamsulosin: a double-blind, placebo-controlled, randomized, multicenter trial. Ann Emerg Med. 2016;67(1):86-95.e2.

Short Take

Low Diagnostic Yield of Blood Cultures in Hospitalized Medical Patients

Prospective cohort study of patients hospitalized on a medical service demonstrated a true positive rate of blood cultures that was lower than previously studied. Using objective clinical predictors may improve likelihood of true positive blood cultures.

Citation: Linsenmeyer K, Gupta K, Strymish JM, Dhanani M, Brecher SM, Breu AC. Culture if spikes? Indications and yield of blood cultures in hospitalized medical patients [published online ahead of print January 13, 2016]. J Hosp Med. doi:10.1002/jhm.2541.

Clinical question: Do claim-prone physicians account for a substantial share of all paid malpractice claims?

Background: Many studies have compared physicians who have multiple malpractice claims against them with colleagues who have few or no claims against them and have identified systemic differences in their age, sex, and specialty. However, only a few published studies have analyzed the nature of maldistribution itself.

Study design: Retrospective cohort study.

Setting: Using data from the National Practitioner Data Bank (NPDB).

Synopsis: The NPDB is a confidential data repository created by Congress in 1986. Information was obtained on all payments reported to the NPDB against physicians in the U.S. between January 1, 2005, and December 31, 2014. The study sample consisted of 66,426 paid claims against 54,099 physicians.

Physicians in four specialty groups accounted for more than half the claims: internal medicine (15%), obstetrics and gynecology (13%), general surgery (12%), and family medicine (11%). One percent of all physicians accounted for 32% of paid claims. Physicians’ risk of future paid claims increased monotonically with their number of previous paid claims. Physicians who had two paid claims had almost twice the risk of having another one (HR, 1.97; 95% CI, 1.86–2.07).

Risk also varied widely according to specialty. Compared with internal medicine physicians, neurosurgeons had approximately double the risk of recurrence (HR, 2.32; 95% CI, 1.77–3.03).

The study has some limitations. Some malpractice payments do not reach the NPDB. The study also focused on paid claims only.

Bottom line: A small group of U.S. physicians accounted for a disproportionately large share of paid malpractice claims. Several physician characteristics, most notably the number of previous claims and physician specialty, were significantly associated with recurrence of claims.

Citation: Studdert DM, Bismark MM, Mello MM, Singh H, Spittal MJ. Prevalence and characteristics of physicians prone to malpractice claims. N Engl J Med. 2016;374(4):354-362. doi:10.1056/nejmsa1506137.

Clinical question: Do claim-prone physicians account for a substantial share of all paid malpractice claims?

Background: Many studies have compared physicians who have multiple malpractice claims against them with colleagues who have few or no claims against them and have identified systemic differences in their age, sex, and specialty. However, only a few published studies have analyzed the nature of maldistribution itself.

Study design: Retrospective cohort study.

Setting: Using data from the National Practitioner Data Bank (NPDB).

Synopsis: The NPDB is a confidential data repository created by Congress in 1986. Information was obtained on all payments reported to the NPDB against physicians in the U.S. between January 1, 2005, and December 31, 2014. The study sample consisted of 66,426 paid claims against 54,099 physicians.

Physicians in four specialty groups accounted for more than half the claims: internal medicine (15%), obstetrics and gynecology (13%), general surgery (12%), and family medicine (11%). One percent of all physicians accounted for 32% of paid claims. Physicians’ risk of future paid claims increased monotonically with their number of previous paid claims. Physicians who had two paid claims had almost twice the risk of having another one (HR, 1.97; 95% CI, 1.86–2.07).

Risk also varied widely according to specialty. Compared with internal medicine physicians, neurosurgeons had approximately double the risk of recurrence (HR, 2.32; 95% CI, 1.77–3.03).

The study has some limitations. Some malpractice payments do not reach the NPDB. The study also focused on paid claims only.

Bottom line: A small group of U.S. physicians accounted for a disproportionately large share of paid malpractice claims. Several physician characteristics, most notably the number of previous claims and physician specialty, were significantly associated with recurrence of claims.

Citation: Studdert DM, Bismark MM, Mello MM, Singh H, Spittal MJ. Prevalence and characteristics of physicians prone to malpractice claims. N Engl J Med. 2016;374(4):354-362. doi:10.1056/nejmsa1506137.

Clinical question: Do claim-prone physicians account for a substantial share of all paid malpractice claims?

Background: Many studies have compared physicians who have multiple malpractice claims against them with colleagues who have few or no claims against them and have identified systemic differences in their age, sex, and specialty. However, only a few published studies have analyzed the nature of maldistribution itself.

Study design: Retrospective cohort study.

Setting: Using data from the National Practitioner Data Bank (NPDB).

Synopsis: The NPDB is a confidential data repository created by Congress in 1986. Information was obtained on all payments reported to the NPDB against physicians in the U.S. between January 1, 2005, and December 31, 2014. The study sample consisted of 66,426 paid claims against 54,099 physicians.

Physicians in four specialty groups accounted for more than half the claims: internal medicine (15%), obstetrics and gynecology (13%), general surgery (12%), and family medicine (11%). One percent of all physicians accounted for 32% of paid claims. Physicians’ risk of future paid claims increased monotonically with their number of previous paid claims. Physicians who had two paid claims had almost twice the risk of having another one (HR, 1.97; 95% CI, 1.86–2.07).

Risk also varied widely according to specialty. Compared with internal medicine physicians, neurosurgeons had approximately double the risk of recurrence (HR, 2.32; 95% CI, 1.77–3.03).

The study has some limitations. Some malpractice payments do not reach the NPDB. The study also focused on paid claims only.

Bottom line: A small group of U.S. physicians accounted for a disproportionately large share of paid malpractice claims. Several physician characteristics, most notably the number of previous claims and physician specialty, were significantly associated with recurrence of claims.

Citation: Studdert DM, Bismark MM, Mello MM, Singh H, Spittal MJ. Prevalence and characteristics of physicians prone to malpractice claims. N Engl J Med. 2016;374(4):354-362. doi:10.1056/nejmsa1506137.

Clinical question: What is the association of preoperative frailty on one-year postoperative mortality?

Background: Frailty is an aggregate expression of susceptibility to poor outcomes owing to age and disease-related deficits that accumulate with multiple domains. Frailty in this study was defined by the Johns Hopkins Adjusted Clinical Groups (ACG) frailty-defining diagnoses indicator. It is a binary variable that uses 12 clusters of frailty-defining diagnoses.

Study design: Population-based retrospective cohort study.

Setting: All hospital and physician services funded through the public health care system in Toronto.

Synopsis: The study had 202,980 patients who underwent major elective non-cardiac surgery. Frailty-defining diagnoses were present in 6,289 patients (3.1%). Mean age for the frail population was about 77 years. Joint replacements were the most common procedures for the frail and non-frail groups. Knee replacements were more prevalent in the non-frail group. One year after surgery, 855 frail patients (13.6%) and 9,433 non-frail patients (4.8%) died (unadjusted hazard ratio [HR], 2.98; 95% CI, 2.78–3.20). When adjusted for age, sex, neighborhood income quintile, and procedure, one-year mortality risk remained significantly higher in the frail group. One-year risk of death was significantly higher in frail patients for all surgical procedures, especially with total joint arthroplasty.

The relative hazard ratio of mortality in frail versus non-frail was extremely high in the early postoperative period, most notably at postoperative day three.

One major weakness of the study is that there is no universal definition of frailty, plus the results are difficult to generalize across populations.

Bottom line: Presence of preoperative frailty-defining diagnoses is associated with increased risk for one-year postoperative mortality; the risk appears to be very high in the early postoperative period.

Citation: McIsaac D, Bryson G, van Walraven C. Association of frailty and 1-year postoperative mortality following major elective noncardiac surgery: a population-based cohort study [published online ahead of print January 20, 2016]. JAMA Surg. doi:10.1001/jamasurg.2015.5085.

Short Take

Early Discharge Associated with Longer Length of Stay

Retrospective analysis showed early discharge before noon was associated with longer length of stay, especially among emergent admissions. However, multiple metrics should be used to measure true effectiveness of an early discharge program.

Citation: Rajkomar A, Valencia V, Novelero M, Mourad M, Auerbach A. The association between discharge before noon and length of stay in medical and surgical patients [published online ahead of print December 30, 2015]. J Hosp Med. doi:10.1002/jhm.2529.

Clinical question: What is the association of preoperative frailty on one-year postoperative mortality?

Background: Frailty is an aggregate expression of susceptibility to poor outcomes owing to age and disease-related deficits that accumulate with multiple domains. Frailty in this study was defined by the Johns Hopkins Adjusted Clinical Groups (ACG) frailty-defining diagnoses indicator. It is a binary variable that uses 12 clusters of frailty-defining diagnoses.

Study design: Population-based retrospective cohort study.

Setting: All hospital and physician services funded through the public health care system in Toronto.

Synopsis: The study had 202,980 patients who underwent major elective non-cardiac surgery. Frailty-defining diagnoses were present in 6,289 patients (3.1%). Mean age for the frail population was about 77 years. Joint replacements were the most common procedures for the frail and non-frail groups. Knee replacements were more prevalent in the non-frail group. One year after surgery, 855 frail patients (13.6%) and 9,433 non-frail patients (4.8%) died (unadjusted hazard ratio [HR], 2.98; 95% CI, 2.78–3.20). When adjusted for age, sex, neighborhood income quintile, and procedure, one-year mortality risk remained significantly higher in the frail group. One-year risk of death was significantly higher in frail patients for all surgical procedures, especially with total joint arthroplasty.

The relative hazard ratio of mortality in frail versus non-frail was extremely high in the early postoperative period, most notably at postoperative day three.

One major weakness of the study is that there is no universal definition of frailty, plus the results are difficult to generalize across populations.

Bottom line: Presence of preoperative frailty-defining diagnoses is associated with increased risk for one-year postoperative mortality; the risk appears to be very high in the early postoperative period.

Citation: McIsaac D, Bryson G, van Walraven C. Association of frailty and 1-year postoperative mortality following major elective noncardiac surgery: a population-based cohort study [published online ahead of print January 20, 2016]. JAMA Surg. doi:10.1001/jamasurg.2015.5085.

Short Take

Early Discharge Associated with Longer Length of Stay

Retrospective analysis showed early discharge before noon was associated with longer length of stay, especially among emergent admissions. However, multiple metrics should be used to measure true effectiveness of an early discharge program.

Citation: Rajkomar A, Valencia V, Novelero M, Mourad M, Auerbach A. The association between discharge before noon and length of stay in medical and surgical patients [published online ahead of print December 30, 2015]. J Hosp Med. doi:10.1002/jhm.2529.

Clinical question: What is the association of preoperative frailty on one-year postoperative mortality?

Background: Frailty is an aggregate expression of susceptibility to poor outcomes owing to age and disease-related deficits that accumulate with multiple domains. Frailty in this study was defined by the Johns Hopkins Adjusted Clinical Groups (ACG) frailty-defining diagnoses indicator. It is a binary variable that uses 12 clusters of frailty-defining diagnoses.

Study design: Population-based retrospective cohort study.

Setting: All hospital and physician services funded through the public health care system in Toronto.

Synopsis: The study had 202,980 patients who underwent major elective non-cardiac surgery. Frailty-defining diagnoses were present in 6,289 patients (3.1%). Mean age for the frail population was about 77 years. Joint replacements were the most common procedures for the frail and non-frail groups. Knee replacements were more prevalent in the non-frail group. One year after surgery, 855 frail patients (13.6%) and 9,433 non-frail patients (4.8%) died (unadjusted hazard ratio [HR], 2.98; 95% CI, 2.78–3.20). When adjusted for age, sex, neighborhood income quintile, and procedure, one-year mortality risk remained significantly higher in the frail group. One-year risk of death was significantly higher in frail patients for all surgical procedures, especially with total joint arthroplasty.

The relative hazard ratio of mortality in frail versus non-frail was extremely high in the early postoperative period, most notably at postoperative day three.

One major weakness of the study is that there is no universal definition of frailty, plus the results are difficult to generalize across populations.

Bottom line: Presence of preoperative frailty-defining diagnoses is associated with increased risk for one-year postoperative mortality; the risk appears to be very high in the early postoperative period.

Citation: McIsaac D, Bryson G, van Walraven C. Association of frailty and 1-year postoperative mortality following major elective noncardiac surgery: a population-based cohort study [published online ahead of print January 20, 2016]. JAMA Surg. doi:10.1001/jamasurg.2015.5085.

Short Take

Early Discharge Associated with Longer Length of Stay

Retrospective analysis showed early discharge before noon was associated with longer length of stay, especially among emergent admissions. However, multiple metrics should be used to measure true effectiveness of an early discharge program.

Citation: Rajkomar A, Valencia V, Novelero M, Mourad M, Auerbach A. The association between discharge before noon and length of stay in medical and surgical patients [published online ahead of print December 30, 2015]. J Hosp Med. doi:10.1002/jhm.2529.

Case

A 66-year-old man with diabetes mellitus type 2 and hypertension underwent left total knee replacement. Several hours after surgery, the patient developed atrial fibrillation (AF). He was asymptomatic, and reversible causes of AF were ruled out. Approximately 18 hours later, he spontaneously reverted back to sinus rhythm. Should this patient, who has no known prior history of AF and a CHA2DS2-VASc score of 3, be started on anticoagulation?

Background

Hospitalists are commonly consulted for evaluation and management of postoperative atrial fibrillation (POAF). The incidence of new-onset AF associated with non-cardiac surgery is approximately 2% and may be more frequent in an elderly population.1 The increased adrenergic tone associated with surgery is thought to elicit AF in some patients. POAF has also been associated with positive fluid balance, electrolyte abnormalities, and hypoxemia.2 Some of these patients will spontaneously revert back to sinus rhythm after these issues are reversed. Others will go on to develop chronic or paroxysmal AF that persists indefinitely. It is also likely that some patients with POAF, in fact, already had asymptomatic AF that was simply undetected prior to hospitalization.

Hospitalists are faced with the difficult task of determining which patients with POAF will benefit from either short-term or long-term anticoagulation. This has not been well studied in postsurgical patients, in contrast to medical patients in whom stroke risk from AF has been very well-characterized. The decision may be further complicated by bleeding risk (associated with either some surgeries or with patient-dependent factors).3

It is worth noting that following major cardiac or thoracic surgery, POAF is common; the incidence ranges from 10% to 60%. In these cases, POAF may be triggered by transient atrial ischemia or by postoperative inflammation and may have a different natural history from POAF in non-cardiac surgery patients in terms of both reversibility and stroke risk. More retrospective data are available regarding cardiothoracic surgery patients.

Previous American Heart Association (AHA) and American College of Cardiology (ACC) guidelines stated that POAF lasting longer than 48 hours warranted anticoagulation. This recommendation was removed from the newest update. The 2014 updated AHA/ACC guidelines are less absolute and now state only that “it is reasonable to administer antithrombotic medication in patients who developed postoperative AF, as recommended for nonsurgical patients” (Level of Evidence: B) in regard to cardiothoracic surgery.4

There is no specific recommendation regarding POAF for non-cardiac surgery patients. The current guidelines are likely purposefully vague due to the lack of direct evidence. The following is a review of the existing literature and a suggested approach to anticoagulation in POAF.

Review

How common is postoperative atrial fibrillation? New-onset AF during hospitalization is known to occur in association with many acute conditions including surgery, infection, and myocardial infarction. About half of the cases of in-hospital new-onset AF are associated with surgery. AF is more commonly seen in surgery that involves the thoracic cavity and cardiac structures. In a cross-sectional epidemiologic study of 22 million patients in California, 20.8% of patients undergoing cardiac surgery developed POAF compared with only 1.3% of patients undergoing non-cardiac surgery.5 A smaller study of non-cardiac surgery patients found a 30-day POAF incidence of 0.37%.2

Does postoperative atrial fibrillation increase the short-term risk of stroke? A major concern in AF is the risk of stroke. It is well-established that prolonged or recurrent AF increases the risk for stroke over months or years, but do short episodes of POAF increase stroke risk to a significant degree? Most of the studies in the literature focus on perioperative stroke risk specifically in cardiothoracic surgery. A prospective study of 4,000 patients undergoing cardiac surgery found that the in-hospital postoperative stroke risk was 3.3% in patients with POAF compared to 1.4% in patients without POAF (P<0.01).6 Similar outcomes were seen in a VA study looking at patients who underwent open heart surgery: Stroke risk was 5.3% at six months in POAF patients compared to 2.4% in those without POAF.7 Another study of coronary artery bypass graft (CABG) patients with a follow-up of almost six years showed a stroke risk of 12.1% in POAF patients compared to 8.4% in those without POAF.8

 

It is not clear that all of the increase in stroke risk is a direct effect of POAF. Indeed, in a retrospective analysis of almost 3,000 CABG patients, 1.1% suffered a stroke during their hospital stay. Fewer than half of those had a cardiac rhythm other than sinus rhythm. In the 15 stroke patients who developed POAF, nine presented with stroke symptoms prior to the first episode of AF.9 The authors suggest that aggressive anticoagulation for POAF would not have prevented most of these events.

Furthermore, the rate of in-hospital stroke after non-cardiac surgery is probably much lower, though it has not been as well studied. These data raise some questions as to the benefit of anticoagulation in the immediate postoperative period, though it is difficult to draw firm conclusions without randomized data.

What about non-cardiac surgery? There is less evidence available for patients undergoing non-cardiac surgery, but the few studies that do exist also point to higher stroke risk in patients with POAF. A large population-based study using ICD codes found that the one-year risk of stroke for patients with POAF after non-cardiac surgery was 1.47% compared to 0.36% in non-cardiac surgery patients without POAF (P<0.001). Based on these data, the long-term stroke risk after POAF in non-cardiac surgery patients is similar to that of medical AF patients with a CHA2DS2-VASc score of 2. The authors of this study suggest that transient POAF after non-cardiac surgery may carry a long-term stroke risk similar to any other AF diagnosis.10 However, this study design is subject to significant ascertainment bias (i.e., they may have unintentionally captured some patients with preexisting or prolonged AF), and further research is needed to better delineate this risk.

Does increased stroke risk translate into increased mortality? In a retrospective study of 17,000 patients, El-Chami et al found that POAF after CABG was associated with decreased survival after one year (90% versus 96%) and 10 years (55% versus 70%).11 However, those patients who develop POAF may be sicker overall.

Another study showed that death due to stroke occurred in 4.2% of POAF patients compared to 0.2% of non-POAF patients in a five-year period.12 Based on these studies, POAF is likely associated with increased mortality, but there may be other unaccounted variables. Nevertheless, the increased mortality associated with POAF in these populations is similar to that seen for non-surgical population-based studies13 and provides support that those with newly diagnosed AF in the post-surgical setting should at least be followed closely to assess for recurrence.

What is a patient’s risk of developing atrial fibrillation later in life? When we choose to anticoagulate patients with POAF, we then have to determine whether they should be committed to long-term anticoagulation. It is thought that many cases of POAF are transient; however, some patients will go on to have persistent or paroxysmal AF after discharge.

A retrospective study examined 571 patients who underwent CABG, 30% of whom had POAF during the index admission. After five years of follow-up, 25% of those with POAF were diagnosed with paroxysmal or persistent AF after discharge compared to only 3% of patients without POAF. Researchers did this by looking at the most recent ECG, if done in the last year, or by obtaining a new ECG at the five-year point.12 By this method, it is probable that some diagnoses of paroxysmal AF were missed.

In another study of about 300 CABG patients, about 20% of patients with POAF also went on to develop post-discharge AF, defined as symptomatic AF that led to medical evaluation. As in the previous study, it is likely that there were undetected episodes of AF.14 Thus, in cardiothoracic surgery patients, some but not all of whom develop POAF have recurrent or ongoing AF. For this reason, if anticoagulation is started, it may be reasonable to stop anticoagulation after weeks or months if ongoing AF is not apparent.

 

What is the risk of postoperative bleeding if anticoagulation is started? Any decision about the benefits of anticoagulation must be weighed against the risks, most notably the risk of serious or life-threatening bleeding. This risk may be heightened in the immediate perioperative period. Discussions should always take place with our surgical colleagues about type of surgery, intraoperative complications, and postoperative risk of bleeding.

Anticoagulation, if indicated, should not be started until postoperative bleeding risk is deemed appropriately low. That said, the 2015 BRIDGE trial (looking at the benefits and risks of “bridging” patients before surgery) provides some peripheral but meaningful information about postoperative bleeding risk. In this study, patients with preexisting AF who underwent low-bleeding-risk surgery and were bridged on day one after surgery with therapeutic doses of unfractionated or low-molecular-weight heparin had a significantly higher risk of postoperative bleeding compared to non-bridged patients, with a number needed to harm of 50.15 It may be reasonable—and likely safer—to wait a couple days to start anticoagulation for patients with POAF.

What is the expert’s opinion? We asked one of our cardiac electrophysiologists what her approach is to this situation. In general, if a patient has a low stroke risk and is in AF for fewer than 24 hours, it is reasonable to defer anticoagulation and follow as an outpatient. Regardless of risk, if AF is sustained for more than 24 hours, we recommend at least four weeks of anticoagulation and close outpatient follow-up, which should include a period of ambulatory monitoring to determine the need for continued anticoagulation. We also recommend considering what comprises the patient’s stroke risk.

For example, if the CHA2DS2-VASc score is 2 but the points come from being a female with coronary artery disease, we would consider forgoing anticoagulation but arranging for an outpatient cardiac monitor with cardiology follow-up. If the patient has a history of stroke or TIA, we recommend continuing anticoagulation indefinitely.

Back to the Case

Given our patient’s episode of POAF lasted fewer than 24 hours, it would be reasonable to hold off starting anticoagulation, but he should be followed as an outpatient with ambulatory monitoring at a minimum, monitoring for recurrence. If he were to develop recurrent AF, then he would warrant anticoagulation based on an annual stroke risk of 3.2% as determined by a CHA2DS2-VASc score of 3.

Bottom Line

Our strategy is as follows: If a patient has a low stroke risk (i.e., CHA2DS2-VASc score <2) and is in AF for fewer than 24 hours, anticoagulation is not started, but outpatient follow-up is arranged to monitor symptoms. Regardless of stroke risk, if a patient is in AF for more than 24 hours, we initiate and continue anticoagulation for a minimum of four weeks and arrange outpatient follow-up with a period of ambulatory monitoring to determine need for continued anticoagulation. If a patient has a high stroke risk (CHA2DS2-VASc >2) or if their risk factors include a history of stroke or TIA, anticoagulation is started and continued indefinitely. Risk-benefit discussion is held with the patient, especially with regard to bleeding risk, prior to anticoagulation initiation. If the individual patient’s situation presents further nuance, we ask for the assistance of our cardiology or cardiac electrophysiology colleagues.

Final Thought

None of the mentioned studies investigated or included newer oral anticoagulants. Risk-benefit ratios may change (potentially considerably) with these agents. Further study is needed. We expect, in due time, studies will look at the question of POAF in regard to newer anticoagulant agents, and perhaps then our decision making will change. TH

---

 

Dr. Evavold is a resident in the hospitalist training program, while Dr. Lessing and Dr. Merritt are hospitalists in the Department of Internal Medicine at the University of Colorado. Dr. Tzou is a cardiologist in the section of electrophysiology at the University of Colorado.

References:

1. POISE Study Group, Devereaux PJ, Yang H, et al. Effects of extended-release metoprolol succinate in patients undergoing non-cardiac surgery (POISE trial): a randomised controlled trial. Lancet. 2008;371(9627):1839-1847. doi:10.1016/s0140-6736(08)60601-7.
2. Christians K, Wu B, Quebbeman E, Brasel K. Postoperative atrial fibrillation in noncardiothoracic surgical patients. Am J Surg. 2001;182(6):713-715. doi:10.1016/s0002-9610(01)00799-1.
3. Pisters R, Lane DA, Nieuwlaat R, de Vos CB, Crijns HJ, Lip GY. A novel user-friendly score (HAS-BLED) to assess 1-year risk of major bleeding in patients with atrial fibrillation: the Euro Heart Survey. Chest. 2010;138(5):1093-1100. doi:10.1378/chest.10-0134.
4. Fleisher L, Beckman J, Brown K, et al. ACC/AHA 2007 guidelines on perioperative cardiovascular evaluation and care for noncardiac surgery: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (writing committee to revise the 2002 guidelines on perioperative cardiovascular evaluation for noncardiac surgery). Circulation. 2007;116(17):e418-e500. doi:10.1161/circulationaha.107.185699.
5. Walkey A, Benjamin E, Lubitz S. New-onset atrial fibrillation during hospitalization. J Am Coll Cardiol. 2014;64(22):2432-2433. doi:10.1016/j.jacc.2014.09.034.
6. Creswell L, Schuessler R, Rosenbloom M, Cox J. Hazards of postoperative atrial arrhythmias. Ann Thorac Surg. 1993;56(3):539-549. doi:10.1016/0003-4975(93)90894-n.
7. Almassi G, Schowalter T, Nicolosi A, et al. Atrial fibrillation after cardiac surgery: a major morbid event? Ann Surg. 1997;226(4):501-513.
8. Horwich P, Buth K, Légaré J. New onset postoperative atrial fibrillation is associated with a long-term risk for stroke and death following cardiac surgery. J Card Surg. 2013;28(1):8-13. doi:10.1111/jocs.12033.
9. Kollar A, Lick S, Vasquez K, Conti V. Relationship of atrial fibrillation and stroke after coronary artery bypass graft surgery: when is anticoagulation indicated? Ann Thorac Surg. 2006;82(2):515-523. doi:10.1016/j.athoracsur.2006.03.037.
10. Gialdini G, Nearing K, Bhave P, et al. Perioperative atrial fibrillation and the long-term risk of ischemic stroke. JAMA. 2014;312(6):616. doi:10.1001/jama.2014.9143.
11. El-Chami M, Kilgo P, Thourani V, et al. New-onset atrial fibrillation predicts long-term mortality after coronary artery bypass graft. J Am Coll Cardiol. 2010;55(13):1370-1376. doi:10.1016/j.jacc.2009.10.058.
12. Ahlsson A, Fengsrud E, Bodin L, Englund A. Postoperative atrial fibrillation in patients undergoing aortocoronary bypass surgery carries an eightfold risk of future atrial fibrillation and a doubled cardiovascular mortality. Euro J Cardiothorac Surg. 2010;37(6):1353-1359. doi:10.1016/j.ejcts.2009.12.033.
13. Benjamin EJ, Wolf PA, D’Agostino RB, Silbershatz H, Kannel WB, Levy D. Impact of atrial fibrillation on the risk of death: the Framingham Heart Study. Circulation. 1998;98(10):946-952.
14. Antonelli D, Peres D, Freedberg N, Feldman A, Rosenfeld T. Incidence of postdischarge symptomatic paroxysmal atrial fibrillation in patients who underwent coronary artery bypass graft: long-term follow-up. Pacing Clin Electrophysiol. 2004;27(3):365-367. doi:10.1111/j.1540-8159.2004.00443.x.
15. Douketis J, Spyropoulos A, Kaatz S, et al. Perioperative bridging anticoagulation in patients with atrial fibrillation. N Engl J Med. 2015;373(9):823-833. doi:10.1056/nejmoa1501035.

Case

A 66-year-old man with diabetes mellitus type 2 and hypertension underwent left total knee replacement. Several hours after surgery, the patient developed atrial fibrillation (AF). He was asymptomatic, and reversible causes of AF were ruled out. Approximately 18 hours later, he spontaneously reverted back to sinus rhythm. Should this patient, who has no known prior history of AF and a CHA2DS2-VASc score of 3, be started on anticoagulation?

Background

Hospitalists are commonly consulted for evaluation and management of postoperative atrial fibrillation (POAF). The incidence of new-onset AF associated with non-cardiac surgery is approximately 2% and may be more frequent in an elderly population.1 The increased adrenergic tone associated with surgery is thought to elicit AF in some patients. POAF has also been associated with positive fluid balance, electrolyte abnormalities, and hypoxemia.2 Some of these patients will spontaneously revert back to sinus rhythm after these issues are reversed. Others will go on to develop chronic or paroxysmal AF that persists indefinitely. It is also likely that some patients with POAF, in fact, already had asymptomatic AF that was simply undetected prior to hospitalization.

Hospitalists are faced with the difficult task of determining which patients with POAF will benefit from either short-term or long-term anticoagulation. This has not been well studied in postsurgical patients, in contrast to medical patients in whom stroke risk from AF has been very well-characterized. The decision may be further complicated by bleeding risk (associated with either some surgeries or with patient-dependent factors).3

It is worth noting that following major cardiac or thoracic surgery, POAF is common; the incidence ranges from 10% to 60%. In these cases, POAF may be triggered by transient atrial ischemia or by postoperative inflammation and may have a different natural history from POAF in non-cardiac surgery patients in terms of both reversibility and stroke risk. More retrospective data are available regarding cardiothoracic surgery patients.

Previous American Heart Association (AHA) and American College of Cardiology (ACC) guidelines stated that POAF lasting longer than 48 hours warranted anticoagulation. This recommendation was removed from the newest update. The 2014 updated AHA/ACC guidelines are less absolute and now state only that “it is reasonable to administer antithrombotic medication in patients who developed postoperative AF, as recommended for nonsurgical patients” (Level of Evidence: B) in regard to cardiothoracic surgery.4

There is no specific recommendation regarding POAF for non-cardiac surgery patients. The current guidelines are likely purposefully vague due to the lack of direct evidence. The following is a review of the existing literature and a suggested approach to anticoagulation in POAF.

Review

How common is postoperative atrial fibrillation? New-onset AF during hospitalization is known to occur in association with many acute conditions including surgery, infection, and myocardial infarction. About half of the cases of in-hospital new-onset AF are associated with surgery. AF is more commonly seen in surgery that involves the thoracic cavity and cardiac structures. In a cross-sectional epidemiologic study of 22 million patients in California, 20.8% of patients undergoing cardiac surgery developed POAF compared with only 1.3% of patients undergoing non-cardiac surgery.5 A smaller study of non-cardiac surgery patients found a 30-day POAF incidence of 0.37%.2

Does postoperative atrial fibrillation increase the short-term risk of stroke? A major concern in AF is the risk of stroke. It is well-established that prolonged or recurrent AF increases the risk for stroke over months or years, but do short episodes of POAF increase stroke risk to a significant degree? Most of the studies in the literature focus on perioperative stroke risk specifically in cardiothoracic surgery. A prospective study of 4,000 patients undergoing cardiac surgery found that the in-hospital postoperative stroke risk was 3.3% in patients with POAF compared to 1.4% in patients without POAF (P<0.01).6 Similar outcomes were seen in a VA study looking at patients who underwent open heart surgery: Stroke risk was 5.3% at six months in POAF patients compared to 2.4% in those without POAF.7 Another study of coronary artery bypass graft (CABG) patients with a follow-up of almost six years showed a stroke risk of 12.1% in POAF patients compared to 8.4% in those without POAF.8

 

It is not clear that all of the increase in stroke risk is a direct effect of POAF. Indeed, in a retrospective analysis of almost 3,000 CABG patients, 1.1% suffered a stroke during their hospital stay. Fewer than half of those had a cardiac rhythm other than sinus rhythm. In the 15 stroke patients who developed POAF, nine presented with stroke symptoms prior to the first episode of AF.9 The authors suggest that aggressive anticoagulation for POAF would not have prevented most of these events.

Furthermore, the rate of in-hospital stroke after non-cardiac surgery is probably much lower, though it has not been as well studied. These data raise some questions as to the benefit of anticoagulation in the immediate postoperative period, though it is difficult to draw firm conclusions without randomized data.

What about non-cardiac surgery? There is less evidence available for patients undergoing non-cardiac surgery, but the few studies that do exist also point to higher stroke risk in patients with POAF. A large population-based study using ICD codes found that the one-year risk of stroke for patients with POAF after non-cardiac surgery was 1.47% compared to 0.36% in non-cardiac surgery patients without POAF (P<0.001). Based on these data, the long-term stroke risk after POAF in non-cardiac surgery patients is similar to that of medical AF patients with a CHA2DS2-VASc score of 2. The authors of this study suggest that transient POAF after non-cardiac surgery may carry a long-term stroke risk similar to any other AF diagnosis.10 However, this study design is subject to significant ascertainment bias (i.e., they may have unintentionally captured some patients with preexisting or prolonged AF), and further research is needed to better delineate this risk.

Does increased stroke risk translate into increased mortality? In a retrospective study of 17,000 patients, El-Chami et al found that POAF after CABG was associated with decreased survival after one year (90% versus 96%) and 10 years (55% versus 70%).11 However, those patients who develop POAF may be sicker overall.

Another study showed that death due to stroke occurred in 4.2% of POAF patients compared to 0.2% of non-POAF patients in a five-year period.12 Based on these studies, POAF is likely associated with increased mortality, but there may be other unaccounted variables. Nevertheless, the increased mortality associated with POAF in these populations is similar to that seen for non-surgical population-based studies13 and provides support that those with newly diagnosed AF in the post-surgical setting should at least be followed closely to assess for recurrence.

What is a patient’s risk of developing atrial fibrillation later in life? When we choose to anticoagulate patients with POAF, we then have to determine whether they should be committed to long-term anticoagulation. It is thought that many cases of POAF are transient; however, some patients will go on to have persistent or paroxysmal AF after discharge.

A retrospective study examined 571 patients who underwent CABG, 30% of whom had POAF during the index admission. After five years of follow-up, 25% of those with POAF were diagnosed with paroxysmal or persistent AF after discharge compared to only 3% of patients without POAF. Researchers did this by looking at the most recent ECG, if done in the last year, or by obtaining a new ECG at the five-year point.12 By this method, it is probable that some diagnoses of paroxysmal AF were missed.

In another study of about 300 CABG patients, about 20% of patients with POAF also went on to develop post-discharge AF, defined as symptomatic AF that led to medical evaluation. As in the previous study, it is likely that there were undetected episodes of AF.14 Thus, in cardiothoracic surgery patients, some but not all of whom develop POAF have recurrent or ongoing AF. For this reason, if anticoagulation is started, it may be reasonable to stop anticoagulation after weeks or months if ongoing AF is not apparent.

 

What is the risk of postoperative bleeding if anticoagulation is started? Any decision about the benefits of anticoagulation must be weighed against the risks, most notably the risk of serious or life-threatening bleeding. This risk may be heightened in the immediate perioperative period. Discussions should always take place with our surgical colleagues about type of surgery, intraoperative complications, and postoperative risk of bleeding.

Anticoagulation, if indicated, should not be started until postoperative bleeding risk is deemed appropriately low. That said, the 2015 BRIDGE trial (looking at the benefits and risks of “bridging” patients before surgery) provides some peripheral but meaningful information about postoperative bleeding risk. In this study, patients with preexisting AF who underwent low-bleeding-risk surgery and were bridged on day one after surgery with therapeutic doses of unfractionated or low-molecular-weight heparin had a significantly higher risk of postoperative bleeding compared to non-bridged patients, with a number needed to harm of 50.15 It may be reasonable—and likely safer—to wait a couple days to start anticoagulation for patients with POAF.

What is the expert’s opinion? We asked one of our cardiac electrophysiologists what her approach is to this situation. In general, if a patient has a low stroke risk and is in AF for fewer than 24 hours, it is reasonable to defer anticoagulation and follow as an outpatient. Regardless of risk, if AF is sustained for more than 24 hours, we recommend at least four weeks of anticoagulation and close outpatient follow-up, which should include a period of ambulatory monitoring to determine the need for continued anticoagulation. We also recommend considering what comprises the patient’s stroke risk.

For example, if the CHA2DS2-VASc score is 2 but the points come from being a female with coronary artery disease, we would consider forgoing anticoagulation but arranging for an outpatient cardiac monitor with cardiology follow-up. If the patient has a history of stroke or TIA, we recommend continuing anticoagulation indefinitely.

Back to the Case

Given our patient’s episode of POAF lasted fewer than 24 hours, it would be reasonable to hold off starting anticoagulation, but he should be followed as an outpatient with ambulatory monitoring at a minimum, monitoring for recurrence. If he were to develop recurrent AF, then he would warrant anticoagulation based on an annual stroke risk of 3.2% as determined by a CHA2DS2-VASc score of 3.

Bottom Line

Our strategy is as follows: If a patient has a low stroke risk (i.e., CHA2DS2-VASc score <2) and is in AF for fewer than 24 hours, anticoagulation is not started, but outpatient follow-up is arranged to monitor symptoms. Regardless of stroke risk, if a patient is in AF for more than 24 hours, we initiate and continue anticoagulation for a minimum of four weeks and arrange outpatient follow-up with a period of ambulatory monitoring to determine need for continued anticoagulation. If a patient has a high stroke risk (CHA2DS2-VASc >2) or if their risk factors include a history of stroke or TIA, anticoagulation is started and continued indefinitely. Risk-benefit discussion is held with the patient, especially with regard to bleeding risk, prior to anticoagulation initiation. If the individual patient’s situation presents further nuance, we ask for the assistance of our cardiology or cardiac electrophysiology colleagues.

Final Thought

None of the mentioned studies investigated or included newer oral anticoagulants. Risk-benefit ratios may change (potentially considerably) with these agents. Further study is needed. We expect, in due time, studies will look at the question of POAF in regard to newer anticoagulant agents, and perhaps then our decision making will change. TH

---

 

Dr. Evavold is a resident in the hospitalist training program, while Dr. Lessing and Dr. Merritt are hospitalists in the Department of Internal Medicine at the University of Colorado. Dr. Tzou is a cardiologist in the section of electrophysiology at the University of Colorado.

References:

1. POISE Study Group, Devereaux PJ, Yang H, et al. Effects of extended-release metoprolol succinate in patients undergoing non-cardiac surgery (POISE trial): a randomised controlled trial. Lancet. 2008;371(9627):1839-1847. doi:10.1016/s0140-6736(08)60601-7.
2. Christians K, Wu B, Quebbeman E, Brasel K. Postoperative atrial fibrillation in noncardiothoracic surgical patients. Am J Surg. 2001;182(6):713-715. doi:10.1016/s0002-9610(01)00799-1.
3. Pisters R, Lane DA, Nieuwlaat R, de Vos CB, Crijns HJ, Lip GY. A novel user-friendly score (HAS-BLED) to assess 1-year risk of major bleeding in patients with atrial fibrillation: the Euro Heart Survey. Chest. 2010;138(5):1093-1100. doi:10.1378/chest.10-0134.
4. Fleisher L, Beckman J, Brown K, et al. ACC/AHA 2007 guidelines on perioperative cardiovascular evaluation and care for noncardiac surgery: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (writing committee to revise the 2002 guidelines on perioperative cardiovascular evaluation for noncardiac surgery). Circulation. 2007;116(17):e418-e500. doi:10.1161/circulationaha.107.185699.
5. Walkey A, Benjamin E, Lubitz S. New-onset atrial fibrillation during hospitalization. J Am Coll Cardiol. 2014;64(22):2432-2433. doi:10.1016/j.jacc.2014.09.034.
6. Creswell L, Schuessler R, Rosenbloom M, Cox J. Hazards of postoperative atrial arrhythmias. Ann Thorac Surg. 1993;56(3):539-549. doi:10.1016/0003-4975(93)90894-n.
7. Almassi G, Schowalter T, Nicolosi A, et al. Atrial fibrillation after cardiac surgery: a major morbid event? Ann Surg. 1997;226(4):501-513.
8. Horwich P, Buth K, Légaré J. New onset postoperative atrial fibrillation is associated with a long-term risk for stroke and death following cardiac surgery. J Card Surg. 2013;28(1):8-13. doi:10.1111/jocs.12033.
9. Kollar A, Lick S, Vasquez K, Conti V. Relationship of atrial fibrillation and stroke after coronary artery bypass graft surgery: when is anticoagulation indicated? Ann Thorac Surg. 2006;82(2):515-523. doi:10.1016/j.athoracsur.2006.03.037.
10. Gialdini G, Nearing K, Bhave P, et al. Perioperative atrial fibrillation and the long-term risk of ischemic stroke. JAMA. 2014;312(6):616. doi:10.1001/jama.2014.9143.
11. El-Chami M, Kilgo P, Thourani V, et al. New-onset atrial fibrillation predicts long-term mortality after coronary artery bypass graft. J Am Coll Cardiol. 2010;55(13):1370-1376. doi:10.1016/j.jacc.2009.10.058.
12. Ahlsson A, Fengsrud E, Bodin L, Englund A. Postoperative atrial fibrillation in patients undergoing aortocoronary bypass surgery carries an eightfold risk of future atrial fibrillation and a doubled cardiovascular mortality. Euro J Cardiothorac Surg. 2010;37(6):1353-1359. doi:10.1016/j.ejcts.2009.12.033.
13. Benjamin EJ, Wolf PA, D’Agostino RB, Silbershatz H, Kannel WB, Levy D. Impact of atrial fibrillation on the risk of death: the Framingham Heart Study. Circulation. 1998;98(10):946-952.
14. Antonelli D, Peres D, Freedberg N, Feldman A, Rosenfeld T. Incidence of postdischarge symptomatic paroxysmal atrial fibrillation in patients who underwent coronary artery bypass graft: long-term follow-up. Pacing Clin Electrophysiol. 2004;27(3):365-367. doi:10.1111/j.1540-8159.2004.00443.x.
15. Douketis J, Spyropoulos A, Kaatz S, et al. Perioperative bridging anticoagulation in patients with atrial fibrillation. N Engl J Med. 2015;373(9):823-833. doi:10.1056/nejmoa1501035.

Case

A 66-year-old man with diabetes mellitus type 2 and hypertension underwent left total knee replacement. Several hours after surgery, the patient developed atrial fibrillation (AF). He was asymptomatic, and reversible causes of AF were ruled out. Approximately 18 hours later, he spontaneously reverted back to sinus rhythm. Should this patient, who has no known prior history of AF and a CHA2DS2-VASc score of 3, be started on anticoagulation?

Background

Hospitalists are commonly consulted for evaluation and management of postoperative atrial fibrillation (POAF). The incidence of new-onset AF associated with non-cardiac surgery is approximately 2% and may be more frequent in an elderly population.1 The increased adrenergic tone associated with surgery is thought to elicit AF in some patients. POAF has also been associated with positive fluid balance, electrolyte abnormalities, and hypoxemia.2 Some of these patients will spontaneously revert back to sinus rhythm after these issues are reversed. Others will go on to develop chronic or paroxysmal AF that persists indefinitely. It is also likely that some patients with POAF, in fact, already had asymptomatic AF that was simply undetected prior to hospitalization.

Hospitalists are faced with the difficult task of determining which patients with POAF will benefit from either short-term or long-term anticoagulation. This has not been well studied in postsurgical patients, in contrast to medical patients in whom stroke risk from AF has been very well-characterized. The decision may be further complicated by bleeding risk (associated with either some surgeries or with patient-dependent factors).3

It is worth noting that following major cardiac or thoracic surgery, POAF is common; the incidence ranges from 10% to 60%. In these cases, POAF may be triggered by transient atrial ischemia or by postoperative inflammation and may have a different natural history from POAF in non-cardiac surgery patients in terms of both reversibility and stroke risk. More retrospective data are available regarding cardiothoracic surgery patients.

Previous American Heart Association (AHA) and American College of Cardiology (ACC) guidelines stated that POAF lasting longer than 48 hours warranted anticoagulation. This recommendation was removed from the newest update. The 2014 updated AHA/ACC guidelines are less absolute and now state only that “it is reasonable to administer antithrombotic medication in patients who developed postoperative AF, as recommended for nonsurgical patients” (Level of Evidence: B) in regard to cardiothoracic surgery.4

There is no specific recommendation regarding POAF for non-cardiac surgery patients. The current guidelines are likely purposefully vague due to the lack of direct evidence. The following is a review of the existing literature and a suggested approach to anticoagulation in POAF.

Review

How common is postoperative atrial fibrillation? New-onset AF during hospitalization is known to occur in association with many acute conditions including surgery, infection, and myocardial infarction. About half of the cases of in-hospital new-onset AF are associated with surgery. AF is more commonly seen in surgery that involves the thoracic cavity and cardiac structures. In a cross-sectional epidemiologic study of 22 million patients in California, 20.8% of patients undergoing cardiac surgery developed POAF compared with only 1.3% of patients undergoing non-cardiac surgery.5 A smaller study of non-cardiac surgery patients found a 30-day POAF incidence of 0.37%.2

Does postoperative atrial fibrillation increase the short-term risk of stroke? A major concern in AF is the risk of stroke. It is well-established that prolonged or recurrent AF increases the risk for stroke over months or years, but do short episodes of POAF increase stroke risk to a significant degree? Most of the studies in the literature focus on perioperative stroke risk specifically in cardiothoracic surgery. A prospective study of 4,000 patients undergoing cardiac surgery found that the in-hospital postoperative stroke risk was 3.3% in patients with POAF compared to 1.4% in patients without POAF (P<0.01).6 Similar outcomes were seen in a VA study looking at patients who underwent open heart surgery: Stroke risk was 5.3% at six months in POAF patients compared to 2.4% in those without POAF.7 Another study of coronary artery bypass graft (CABG) patients with a follow-up of almost six years showed a stroke risk of 12.1% in POAF patients compared to 8.4% in those without POAF.8

 

It is not clear that all of the increase in stroke risk is a direct effect of POAF. Indeed, in a retrospective analysis of almost 3,000 CABG patients, 1.1% suffered a stroke during their hospital stay. Fewer than half of those had a cardiac rhythm other than sinus rhythm. In the 15 stroke patients who developed POAF, nine presented with stroke symptoms prior to the first episode of AF.9 The authors suggest that aggressive anticoagulation for POAF would not have prevented most of these events.

Furthermore, the rate of in-hospital stroke after non-cardiac surgery is probably much lower, though it has not been as well studied. These data raise some questions as to the benefit of anticoagulation in the immediate postoperative period, though it is difficult to draw firm conclusions without randomized data.

What about non-cardiac surgery? There is less evidence available for patients undergoing non-cardiac surgery, but the few studies that do exist also point to higher stroke risk in patients with POAF. A large population-based study using ICD codes found that the one-year risk of stroke for patients with POAF after non-cardiac surgery was 1.47% compared to 0.36% in non-cardiac surgery patients without POAF (P<0.001). Based on these data, the long-term stroke risk after POAF in non-cardiac surgery patients is similar to that of medical AF patients with a CHA2DS2-VASc score of 2. The authors of this study suggest that transient POAF after non-cardiac surgery may carry a long-term stroke risk similar to any other AF diagnosis.10 However, this study design is subject to significant ascertainment bias (i.e., they may have unintentionally captured some patients with preexisting or prolonged AF), and further research is needed to better delineate this risk.

Does increased stroke risk translate into increased mortality? In a retrospective study of 17,000 patients, El-Chami et al found that POAF after CABG was associated with decreased survival after one year (90% versus 96%) and 10 years (55% versus 70%).11 However, those patients who develop POAF may be sicker overall.

Another study showed that death due to stroke occurred in 4.2% of POAF patients compared to 0.2% of non-POAF patients in a five-year period.12 Based on these studies, POAF is likely associated with increased mortality, but there may be other unaccounted variables. Nevertheless, the increased mortality associated with POAF in these populations is similar to that seen for non-surgical population-based studies13 and provides support that those with newly diagnosed AF in the post-surgical setting should at least be followed closely to assess for recurrence.

What is a patient’s risk of developing atrial fibrillation later in life? When we choose to anticoagulate patients with POAF, we then have to determine whether they should be committed to long-term anticoagulation. It is thought that many cases of POAF are transient; however, some patients will go on to have persistent or paroxysmal AF after discharge.

A retrospective study examined 571 patients who underwent CABG, 30% of whom had POAF during the index admission. After five years of follow-up, 25% of those with POAF were diagnosed with paroxysmal or persistent AF after discharge compared to only 3% of patients without POAF. Researchers did this by looking at the most recent ECG, if done in the last year, or by obtaining a new ECG at the five-year point.12 By this method, it is probable that some diagnoses of paroxysmal AF were missed.

In another study of about 300 CABG patients, about 20% of patients with POAF also went on to develop post-discharge AF, defined as symptomatic AF that led to medical evaluation. As in the previous study, it is likely that there were undetected episodes of AF.14 Thus, in cardiothoracic surgery patients, some but not all of whom develop POAF have recurrent or ongoing AF. For this reason, if anticoagulation is started, it may be reasonable to stop anticoagulation after weeks or months if ongoing AF is not apparent.

 

What is the risk of postoperative bleeding if anticoagulation is started? Any decision about the benefits of anticoagulation must be weighed against the risks, most notably the risk of serious or life-threatening bleeding. This risk may be heightened in the immediate perioperative period. Discussions should always take place with our surgical colleagues about type of surgery, intraoperative complications, and postoperative risk of bleeding.

Anticoagulation, if indicated, should not be started until postoperative bleeding risk is deemed appropriately low. That said, the 2015 BRIDGE trial (looking at the benefits and risks of “bridging” patients before surgery) provides some peripheral but meaningful information about postoperative bleeding risk. In this study, patients with preexisting AF who underwent low-bleeding-risk surgery and were bridged on day one after surgery with therapeutic doses of unfractionated or low-molecular-weight heparin had a significantly higher risk of postoperative bleeding compared to non-bridged patients, with a number needed to harm of 50.15 It may be reasonable—and likely safer—to wait a couple days to start anticoagulation for patients with POAF.

What is the expert’s opinion? We asked one of our cardiac electrophysiologists what her approach is to this situation. In general, if a patient has a low stroke risk and is in AF for fewer than 24 hours, it is reasonable to defer anticoagulation and follow as an outpatient. Regardless of risk, if AF is sustained for more than 24 hours, we recommend at least four weeks of anticoagulation and close outpatient follow-up, which should include a period of ambulatory monitoring to determine the need for continued anticoagulation. We also recommend considering what comprises the patient’s stroke risk.

For example, if the CHA2DS2-VASc score is 2 but the points come from being a female with coronary artery disease, we would consider forgoing anticoagulation but arranging for an outpatient cardiac monitor with cardiology follow-up. If the patient has a history of stroke or TIA, we recommend continuing anticoagulation indefinitely.

Back to the Case

Given our patient’s episode of POAF lasted fewer than 24 hours, it would be reasonable to hold off starting anticoagulation, but he should be followed as an outpatient with ambulatory monitoring at a minimum, monitoring for recurrence. If he were to develop recurrent AF, then he would warrant anticoagulation based on an annual stroke risk of 3.2% as determined by a CHA2DS2-VASc score of 3.

Bottom Line

Our strategy is as follows: If a patient has a low stroke risk (i.e., CHA2DS2-VASc score <2) and is in AF for fewer than 24 hours, anticoagulation is not started, but outpatient follow-up is arranged to monitor symptoms. Regardless of stroke risk, if a patient is in AF for more than 24 hours, we initiate and continue anticoagulation for a minimum of four weeks and arrange outpatient follow-up with a period of ambulatory monitoring to determine need for continued anticoagulation. If a patient has a high stroke risk (CHA2DS2-VASc >2) or if their risk factors include a history of stroke or TIA, anticoagulation is started and continued indefinitely. Risk-benefit discussion is held with the patient, especially with regard to bleeding risk, prior to anticoagulation initiation. If the individual patient’s situation presents further nuance, we ask for the assistance of our cardiology or cardiac electrophysiology colleagues.

Final Thought

None of the mentioned studies investigated or included newer oral anticoagulants. Risk-benefit ratios may change (potentially considerably) with these agents. Further study is needed. We expect, in due time, studies will look at the question of POAF in regard to newer anticoagulant agents, and perhaps then our decision making will change. TH

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Dr. Evavold is a resident in the hospitalist training program, while Dr. Lessing and Dr. Merritt are hospitalists in the Department of Internal Medicine at the University of Colorado. Dr. Tzou is a cardiologist in the section of electrophysiology at the University of Colorado.

References:

1. POISE Study Group, Devereaux PJ, Yang H, et al. Effects of extended-release metoprolol succinate in patients undergoing non-cardiac surgery (POISE trial): a randomised controlled trial. Lancet. 2008;371(9627):1839-1847. doi:10.1016/s0140-6736(08)60601-7.
2. Christians K, Wu B, Quebbeman E, Brasel K. Postoperative atrial fibrillation in noncardiothoracic surgical patients. Am J Surg. 2001;182(6):713-715. doi:10.1016/s0002-9610(01)00799-1.
3. Pisters R, Lane DA, Nieuwlaat R, de Vos CB, Crijns HJ, Lip GY. A novel user-friendly score (HAS-BLED) to assess 1-year risk of major bleeding in patients with atrial fibrillation: the Euro Heart Survey. Chest. 2010;138(5):1093-1100. doi:10.1378/chest.10-0134.
4. Fleisher L, Beckman J, Brown K, et al. ACC/AHA 2007 guidelines on perioperative cardiovascular evaluation and care for noncardiac surgery: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (writing committee to revise the 2002 guidelines on perioperative cardiovascular evaluation for noncardiac surgery). Circulation. 2007;116(17):e418-e500. doi:10.1161/circulationaha.107.185699.
5. Walkey A, Benjamin E, Lubitz S. New-onset atrial fibrillation during hospitalization. J Am Coll Cardiol. 2014;64(22):2432-2433. doi:10.1016/j.jacc.2014.09.034.
6. Creswell L, Schuessler R, Rosenbloom M, Cox J. Hazards of postoperative atrial arrhythmias. Ann Thorac Surg. 1993;56(3):539-549. doi:10.1016/0003-4975(93)90894-n.
7. Almassi G, Schowalter T, Nicolosi A, et al. Atrial fibrillation after cardiac surgery: a major morbid event? Ann Surg. 1997;226(4):501-513.
8. Horwich P, Buth K, Légaré J. New onset postoperative atrial fibrillation is associated with a long-term risk for stroke and death following cardiac surgery. J Card Surg. 2013;28(1):8-13. doi:10.1111/jocs.12033.
9. Kollar A, Lick S, Vasquez K, Conti V. Relationship of atrial fibrillation and stroke after coronary artery bypass graft surgery: when is anticoagulation indicated? Ann Thorac Surg. 2006;82(2):515-523. doi:10.1016/j.athoracsur.2006.03.037.
10. Gialdini G, Nearing K, Bhave P, et al. Perioperative atrial fibrillation and the long-term risk of ischemic stroke. JAMA. 2014;312(6):616. doi:10.1001/jama.2014.9143.
11. El-Chami M, Kilgo P, Thourani V, et al. New-onset atrial fibrillation predicts long-term mortality after coronary artery bypass graft. J Am Coll Cardiol. 2010;55(13):1370-1376. doi:10.1016/j.jacc.2009.10.058.
12. Ahlsson A, Fengsrud E, Bodin L, Englund A. Postoperative atrial fibrillation in patients undergoing aortocoronary bypass surgery carries an eightfold risk of future atrial fibrillation and a doubled cardiovascular mortality. Euro J Cardiothorac Surg. 2010;37(6):1353-1359. doi:10.1016/j.ejcts.2009.12.033.
13. Benjamin EJ, Wolf PA, D’Agostino RB, Silbershatz H, Kannel WB, Levy D. Impact of atrial fibrillation on the risk of death: the Framingham Heart Study. Circulation. 1998;98(10):946-952.
14. Antonelli D, Peres D, Freedberg N, Feldman A, Rosenfeld T. Incidence of postdischarge symptomatic paroxysmal atrial fibrillation in patients who underwent coronary artery bypass graft: long-term follow-up. Pacing Clin Electrophysiol. 2004;27(3):365-367. doi:10.1111/j.1540-8159.2004.00443.x.
15. Douketis J, Spyropoulos A, Kaatz S, et al. Perioperative bridging anticoagulation in patients with atrial fibrillation. N Engl J Med. 2015;373(9):823-833. doi:10.1056/nejmoa1501035.

Clinical question: What is the relationship between crowding in the ED and the number of interventions adopted by the ED to address this?

Background: ED crowding results in long waits, prolonged lengths of stay, and delays in providing treatments, which can result in adverse events. Numerous interventions, including bedside registration, ED observation units, fast track, bed czar, surgical schedule smoothing, and pooled nursing, have been implemented to reduce crowding.

Study design: Retrospective, cross-sectional analysis.

Setting: U.S. hospitals in the National Hospital Ambulatory Medical Care Survey (NHAMCS).

Synopsis: From 2007 to 2010, an average of 341 hospitals per year were analyzed from the NHAMCS, representing 139,502 patient encounters. This study evaluated the adoption of nine crowding interventions at the emergency department level (bedside registration, electronic dashboard, RFID tracking, etc.) and eight crowding interventions at the hospital level (bed czar, pooled nursing, full-capacity protocol, board patients in inpatient hallways, etc.).

Bedside registration, electronic dashboard, RFID tracking, bed census, pooled nursing, full-capacity protocol, and boarding patients in the hallway had the highest statistically significant increases in adoption over the study period.

The average number of interventions adopted increased to 6.6 from 5.2, and more-crowded EDs adopted a greater number of interventions than less-crowded EDs. However, in the most-crowded quartile of EDs, 19% did not use bedside registration, and 94% did not use surgical schedule smoothing.

Given that this study is a retrospective, cross-sectional study, it is difficult to determine causality.

Bottom line: More interventions are being adopted by EDs and hospitals to decrease ED crowding, but several of the busiest EDs and hospitals have room for improvement.

Citation: Warner LS, Pines JM, Chambers JG, Schuur JD. The most crowded US hospital emergency departments did not adopt effective interventions to improve flow, 2007–10. Health Aff. 2015;34(12):2151-2159.

Clinical question: What is the relationship between crowding in the ED and the number of interventions adopted by the ED to address this?

Background: ED crowding results in long waits, prolonged lengths of stay, and delays in providing treatments, which can result in adverse events. Numerous interventions, including bedside registration, ED observation units, fast track, bed czar, surgical schedule smoothing, and pooled nursing, have been implemented to reduce crowding.

Study design: Retrospective, cross-sectional analysis.

Setting: U.S. hospitals in the National Hospital Ambulatory Medical Care Survey (NHAMCS).

Synopsis: From 2007 to 2010, an average of 341 hospitals per year were analyzed from the NHAMCS, representing 139,502 patient encounters. This study evaluated the adoption of nine crowding interventions at the emergency department level (bedside registration, electronic dashboard, RFID tracking, etc.) and eight crowding interventions at the hospital level (bed czar, pooled nursing, full-capacity protocol, board patients in inpatient hallways, etc.).

Bedside registration, electronic dashboard, RFID tracking, bed census, pooled nursing, full-capacity protocol, and boarding patients in the hallway had the highest statistically significant increases in adoption over the study period.

The average number of interventions adopted increased to 6.6 from 5.2, and more-crowded EDs adopted a greater number of interventions than less-crowded EDs. However, in the most-crowded quartile of EDs, 19% did not use bedside registration, and 94% did not use surgical schedule smoothing.

Given that this study is a retrospective, cross-sectional study, it is difficult to determine causality.

Bottom line: More interventions are being adopted by EDs and hospitals to decrease ED crowding, but several of the busiest EDs and hospitals have room for improvement.

Citation: Warner LS, Pines JM, Chambers JG, Schuur JD. The most crowded US hospital emergency departments did not adopt effective interventions to improve flow, 2007–10. Health Aff. 2015;34(12):2151-2159.

Clinical question: What is the relationship between crowding in the ED and the number of interventions adopted by the ED to address this?

Background: ED crowding results in long waits, prolonged lengths of stay, and delays in providing treatments, which can result in adverse events. Numerous interventions, including bedside registration, ED observation units, fast track, bed czar, surgical schedule smoothing, and pooled nursing, have been implemented to reduce crowding.

Study design: Retrospective, cross-sectional analysis.

Setting: U.S. hospitals in the National Hospital Ambulatory Medical Care Survey (NHAMCS).

Synopsis: From 2007 to 2010, an average of 341 hospitals per year were analyzed from the NHAMCS, representing 139,502 patient encounters. This study evaluated the adoption of nine crowding interventions at the emergency department level (bedside registration, electronic dashboard, RFID tracking, etc.) and eight crowding interventions at the hospital level (bed czar, pooled nursing, full-capacity protocol, board patients in inpatient hallways, etc.).

Bedside registration, electronic dashboard, RFID tracking, bed census, pooled nursing, full-capacity protocol, and boarding patients in the hallway had the highest statistically significant increases in adoption over the study period.

The average number of interventions adopted increased to 6.6 from 5.2, and more-crowded EDs adopted a greater number of interventions than less-crowded EDs. However, in the most-crowded quartile of EDs, 19% did not use bedside registration, and 94% did not use surgical schedule smoothing.

Given that this study is a retrospective, cross-sectional study, it is difficult to determine causality.

Bottom line: More interventions are being adopted by EDs and hospitals to decrease ED crowding, but several of the busiest EDs and hospitals have room for improvement.

Citation: Warner LS, Pines JM, Chambers JG, Schuur JD. The most crowded US hospital emergency departments did not adopt effective interventions to improve flow, 2007–10. Health Aff. 2015;34(12):2151-2159.

Clinical question: What is the appropriate frequency of INR monitoring in the hospital and its relationship to the risk of over-anticoagulation and warfarin-related adverse events?

Background: Warfarin use is a common cause of adverse drug events in hospitalized patients due to narrow therapeutic windows, drug interactions, and variability of metabolism. Current guidelines, including those by the American College of Chest Physicians, do not provide recommendations on how often to monitor INR or adjust warfarin dosing in the hospital.

Study design: Retrospective cohort.

Setting: Hospitalized patients included in the Medicare Patient Safety Monitoring System.

Synopsis: The study included 14,217 adult patients ≥18 years of age from the Medicare Patient Safety Monitoring System admitted from 2009 to 2013 with pneumonia, acute cardiac disease (myocardial infarction or congestive heart failure), or surgery and taking warfarin. Of those, 1,055 (7.4%) developed a warfarin-associated adverse event (bleeding, drop in hematocrit ≥3, hematoma, death, intracranial bleeding, or cardiac arrest). Patients admitted for acute cardiac disease (acute myocardial infarction or heart failure) or surgery on warfarin for ≥3 days but not monitored for ≥2 days had more warfarin-associated adverse events (OR 1.48; 95% CI, 1.02–2.17), but this association was not true in pneumonia patients. Cardiac and pneumonia patients with ≥1 day without INR being measured had higher rates of INR ≥6.0 (OR 1.61; 95% CI, 1.07–2.41, and OR 1.92, 95% CI, 1.36–2.71, respectively). A single-day rise in INR ≥0.9 had a likelihood ratio of 4.2 in predicting subsequent INR ≥6.0.

Bottom line: Frequent monitoring of INR may decrease warfarin-associated adverse events in hospitalized patients.

Citation: Metersky ML, Eldridge N, Wang Y, et al. Predictors of warfarin-associated adverse events in hospitalized patients: opportunities to prevent harm. J Hosp Med. 2016;11(4):276-282.

Short Take

CDC Guidelines on Prescribing Opioids

New CDC guidelines for chronic pain management stress the importance of non-pharmacologic (physical therapy, etc.) and non-opioid therapy (NSAIDs, etc.), using opioid therapy only if the expected benefits outweigh the risks.

Citation: CDC. CDC guideline for prescribing opioids for chronic pain. Available at: http://www.cdc.gov/drugoverdose/prescribing/guideline.html. Published March 16, 2016. Accessed April 8, 2016.

Clinical question: What is the appropriate frequency of INR monitoring in the hospital and its relationship to the risk of over-anticoagulation and warfarin-related adverse events?

Background: Warfarin use is a common cause of adverse drug events in hospitalized patients due to narrow therapeutic windows, drug interactions, and variability of metabolism. Current guidelines, including those by the American College of Chest Physicians, do not provide recommendations on how often to monitor INR or adjust warfarin dosing in the hospital.

Study design: Retrospective cohort.

Setting: Hospitalized patients included in the Medicare Patient Safety Monitoring System.

Synopsis: The study included 14,217 adult patients ≥18 years of age from the Medicare Patient Safety Monitoring System admitted from 2009 to 2013 with pneumonia, acute cardiac disease (myocardial infarction or congestive heart failure), or surgery and taking warfarin. Of those, 1,055 (7.4%) developed a warfarin-associated adverse event (bleeding, drop in hematocrit ≥3, hematoma, death, intracranial bleeding, or cardiac arrest). Patients admitted for acute cardiac disease (acute myocardial infarction or heart failure) or surgery on warfarin for ≥3 days but not monitored for ≥2 days had more warfarin-associated adverse events (OR 1.48; 95% CI, 1.02–2.17), but this association was not true in pneumonia patients. Cardiac and pneumonia patients with ≥1 day without INR being measured had higher rates of INR ≥6.0 (OR 1.61; 95% CI, 1.07–2.41, and OR 1.92, 95% CI, 1.36–2.71, respectively). A single-day rise in INR ≥0.9 had a likelihood ratio of 4.2 in predicting subsequent INR ≥6.0.

Bottom line: Frequent monitoring of INR may decrease warfarin-associated adverse events in hospitalized patients.

Citation: Metersky ML, Eldridge N, Wang Y, et al. Predictors of warfarin-associated adverse events in hospitalized patients: opportunities to prevent harm. J Hosp Med. 2016;11(4):276-282.

Short Take

CDC Guidelines on Prescribing Opioids

New CDC guidelines for chronic pain management stress the importance of non-pharmacologic (physical therapy, etc.) and non-opioid therapy (NSAIDs, etc.), using opioid therapy only if the expected benefits outweigh the risks.

Citation: CDC. CDC guideline for prescribing opioids for chronic pain. Available at: http://www.cdc.gov/drugoverdose/prescribing/guideline.html. Published March 16, 2016. Accessed April 8, 2016.

Clinical question: What is the appropriate frequency of INR monitoring in the hospital and its relationship to the risk of over-anticoagulation and warfarin-related adverse events?

Background: Warfarin use is a common cause of adverse drug events in hospitalized patients due to narrow therapeutic windows, drug interactions, and variability of metabolism. Current guidelines, including those by the American College of Chest Physicians, do not provide recommendations on how often to monitor INR or adjust warfarin dosing in the hospital.

Study design: Retrospective cohort.

Setting: Hospitalized patients included in the Medicare Patient Safety Monitoring System.

Synopsis: The study included 14,217 adult patients ≥18 years of age from the Medicare Patient Safety Monitoring System admitted from 2009 to 2013 with pneumonia, acute cardiac disease (myocardial infarction or congestive heart failure), or surgery and taking warfarin. Of those, 1,055 (7.4%) developed a warfarin-associated adverse event (bleeding, drop in hematocrit ≥3, hematoma, death, intracranial bleeding, or cardiac arrest). Patients admitted for acute cardiac disease (acute myocardial infarction or heart failure) or surgery on warfarin for ≥3 days but not monitored for ≥2 days had more warfarin-associated adverse events (OR 1.48; 95% CI, 1.02–2.17), but this association was not true in pneumonia patients. Cardiac and pneumonia patients with ≥1 day without INR being measured had higher rates of INR ≥6.0 (OR 1.61; 95% CI, 1.07–2.41, and OR 1.92, 95% CI, 1.36–2.71, respectively). A single-day rise in INR ≥0.9 had a likelihood ratio of 4.2 in predicting subsequent INR ≥6.0.

Bottom line: Frequent monitoring of INR may decrease warfarin-associated adverse events in hospitalized patients.

Citation: Metersky ML, Eldridge N, Wang Y, et al. Predictors of warfarin-associated adverse events in hospitalized patients: opportunities to prevent harm. J Hosp Med. 2016;11(4):276-282.

Short Take

CDC Guidelines on Prescribing Opioids

New CDC guidelines for chronic pain management stress the importance of non-pharmacologic (physical therapy, etc.) and non-opioid therapy (NSAIDs, etc.), using opioid therapy only if the expected benefits outweigh the risks.

Citation: CDC. CDC guideline for prescribing opioids for chronic pain. Available at: http://www.cdc.gov/drugoverdose/prescribing/guideline.html. Published March 16, 2016. Accessed April 8, 2016.

Clinical question: What is the role for inpatient polysomnograms for children with medical complexity?

Background: Sleep-disordered breathing is more common in certain pediatric populations. Children with neuromuscular disease, craniofacial or tracheobronchial malformations, or developmental delay have up to 10 times the rate of sleep-disordered breathing as compared to the general pediatric population, with a prevalence as high as 40%. It is recommended that patients with neuromuscular conditions get annual polysomnograms (PSGs). The medical complexity and requirement for nursing and respiratory care makes it challenging to obtain routine outpatient PSGs in this population. This study is the first of its kind to examine the characteristics of patients receiving inpatient PSGs and to determine the effects the findings of these studies had on the patients’ care.

Study design: Retrospective case series.

Setting: Single, large, academic medical center.

Synopsis: Eight-five PSGs were completed on 70 patients during the study period. These occurred primarily in the pediatric intensive care unit (50 patients) but also in the neonatal intensive care unit (five patients) and the general pediatric floor (15 patients). The mean age of patients was 6.5 years, and 60% were male.

The most common diagnoses in this group were airway obstruction due to craniofacial abnormalities or defects of the tracheobronchial tree (54%), chronic respiratory failure (34%), hypoxic ischemic encephalopathy (23%), and genetic syndromes (14%). All sleep studies were successfully completed using the center’s dedicated sleep technicians and PSG scoring staff. There were no complications associated with the PSGs.

The most common specific indications for obtaining the PSGs were chronic pulmonary failure with airway obstruction and ventilator requirement assessment. Eighty-nine percent of patients had some abnormality of their PSG. Obstructive sleep apnea, tachypnea and desaturation, and disorders of sleep architecture were the most commonly found abnormalities.

The most common interventions based upon the PSG results were adjustment of ventilator parameters (46%), ENT referral for upper airway assessment (31%), and initiation of positive pressure ventilation (CPAP or BiPAP, 25%). Follow-up PSGs after these interventions demonstrated statistically significant improvement in apnea-hypopnea index, arousal index, and lowest oxygen saturation.

Bottom line: Inpatient PSGs for children with medical complexity are safe and often have significant findings that alter care for the patient.

Citation: Tkachenko N, Singh K, Abreu N, et al. Establishing a role for polysomnography in hospitalized children. Pediatr Neurol. 2016;57:39-45.e1. doi:10.1016/j.pediatrneurol.2015.12.020.

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Dr. Stubblefield is a pediatric hospitalist at Nemours/Alfred I. Dupont Hospital for Children in Wilmington, Del., and assistant professor of pediatrics at Thomas Jefferson Medical College in Philadelphia.

Clinical question: What is the role for inpatient polysomnograms for children with medical complexity?

Background: Sleep-disordered breathing is more common in certain pediatric populations. Children with neuromuscular disease, craniofacial or tracheobronchial malformations, or developmental delay have up to 10 times the rate of sleep-disordered breathing as compared to the general pediatric population, with a prevalence as high as 40%. It is recommended that patients with neuromuscular conditions get annual polysomnograms (PSGs). The medical complexity and requirement for nursing and respiratory care makes it challenging to obtain routine outpatient PSGs in this population. This study is the first of its kind to examine the characteristics of patients receiving inpatient PSGs and to determine the effects the findings of these studies had on the patients’ care.

Study design: Retrospective case series.

Setting: Single, large, academic medical center.

Synopsis: Eight-five PSGs were completed on 70 patients during the study period. These occurred primarily in the pediatric intensive care unit (50 patients) but also in the neonatal intensive care unit (five patients) and the general pediatric floor (15 patients). The mean age of patients was 6.5 years, and 60% were male.

The most common diagnoses in this group were airway obstruction due to craniofacial abnormalities or defects of the tracheobronchial tree (54%), chronic respiratory failure (34%), hypoxic ischemic encephalopathy (23%), and genetic syndromes (14%). All sleep studies were successfully completed using the center’s dedicated sleep technicians and PSG scoring staff. There were no complications associated with the PSGs.

The most common specific indications for obtaining the PSGs were chronic pulmonary failure with airway obstruction and ventilator requirement assessment. Eighty-nine percent of patients had some abnormality of their PSG. Obstructive sleep apnea, tachypnea and desaturation, and disorders of sleep architecture were the most commonly found abnormalities.

The most common interventions based upon the PSG results were adjustment of ventilator parameters (46%), ENT referral for upper airway assessment (31%), and initiation of positive pressure ventilation (CPAP or BiPAP, 25%). Follow-up PSGs after these interventions demonstrated statistically significant improvement in apnea-hypopnea index, arousal index, and lowest oxygen saturation.

Bottom line: Inpatient PSGs for children with medical complexity are safe and often have significant findings that alter care for the patient.

Citation: Tkachenko N, Singh K, Abreu N, et al. Establishing a role for polysomnography in hospitalized children. Pediatr Neurol. 2016;57:39-45.e1. doi:10.1016/j.pediatrneurol.2015.12.020.

---

Dr. Stubblefield is a pediatric hospitalist at Nemours/Alfred I. Dupont Hospital for Children in Wilmington, Del., and assistant professor of pediatrics at Thomas Jefferson Medical College in Philadelphia.

Clinical question: What is the role for inpatient polysomnograms for children with medical complexity?

Background: Sleep-disordered breathing is more common in certain pediatric populations. Children with neuromuscular disease, craniofacial or tracheobronchial malformations, or developmental delay have up to 10 times the rate of sleep-disordered breathing as compared to the general pediatric population, with a prevalence as high as 40%. It is recommended that patients with neuromuscular conditions get annual polysomnograms (PSGs). The medical complexity and requirement for nursing and respiratory care makes it challenging to obtain routine outpatient PSGs in this population. This study is the first of its kind to examine the characteristics of patients receiving inpatient PSGs and to determine the effects the findings of these studies had on the patients’ care.

Study design: Retrospective case series.

Setting: Single, large, academic medical center.

Synopsis: Eight-five PSGs were completed on 70 patients during the study period. These occurred primarily in the pediatric intensive care unit (50 patients) but also in the neonatal intensive care unit (five patients) and the general pediatric floor (15 patients). The mean age of patients was 6.5 years, and 60% were male.

The most common diagnoses in this group were airway obstruction due to craniofacial abnormalities or defects of the tracheobronchial tree (54%), chronic respiratory failure (34%), hypoxic ischemic encephalopathy (23%), and genetic syndromes (14%). All sleep studies were successfully completed using the center’s dedicated sleep technicians and PSG scoring staff. There were no complications associated with the PSGs.

The most common specific indications for obtaining the PSGs were chronic pulmonary failure with airway obstruction and ventilator requirement assessment. Eighty-nine percent of patients had some abnormality of their PSG. Obstructive sleep apnea, tachypnea and desaturation, and disorders of sleep architecture were the most commonly found abnormalities.

The most common interventions based upon the PSG results were adjustment of ventilator parameters (46%), ENT referral for upper airway assessment (31%), and initiation of positive pressure ventilation (CPAP or BiPAP, 25%). Follow-up PSGs after these interventions demonstrated statistically significant improvement in apnea-hypopnea index, arousal index, and lowest oxygen saturation.

Bottom line: Inpatient PSGs for children with medical complexity are safe and often have significant findings that alter care for the patient.

Citation: Tkachenko N, Singh K, Abreu N, et al. Establishing a role for polysomnography in hospitalized children. Pediatr Neurol. 2016;57:39-45.e1. doi:10.1016/j.pediatrneurol.2015.12.020.

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Dr. Stubblefield is a pediatric hospitalist at Nemours/Alfred I. Dupont Hospital for Children in Wilmington, Del., and assistant professor of pediatrics at Thomas Jefferson Medical College in Philadelphia.

Clinical question: What are the factors that promote education in delivering high-value, cost-conscious care?

Background: Healthcare costs are increasing, with most recent numbers showing U.S. expenditures on healthcare of more than $3 trillion, almost 18% of the gross domestic product. High-value care focuses on understanding the benefits, risks, and costs of care and promoting interventions that add value.

Study design: Systematic review.

Setting: Physicians, resident physicians, and medical students in North America, Asia, and Oceania.

Synopsis: Seventy-nine articles were included in the analysis, with 14 being RCTs. Most of the studies were conducted in North America (78.5%) and used a pre-post interventional design (58.2%). Practicing physicians (36.7%) made up the majority of participants in the study, with residents (15.2%) and medical students (6.3%) in smaller numbers. Analysis of the studies identified three factors for successful learning:

• effective transmission of knowledge about prices of services and general health economics, scientific evidence, and patient preferences;
• facilitation of reflective practice through feedback and/or stimulating reflection; and
• creation of a supportive environment.

Bottom line: The most-effective interventions in educating physicians, resident physicians, and medical students on high-value, cost-conscious care are effective transmission of knowledge, reflective practice, and supportive environment.

Citation: Stammen LA, Stalmeijer RE, Paternotte E, et al. Training physicians to provide high-value, cost-conscious care: a systematic review. JAMA. 2015;314(22):2384-2400.

Clinical question: What are the factors that promote education in delivering high-value, cost-conscious care?

Background: Healthcare costs are increasing, with most recent numbers showing U.S. expenditures on healthcare of more than $3 trillion, almost 18% of the gross domestic product. High-value care focuses on understanding the benefits, risks, and costs of care and promoting interventions that add value.

Study design: Systematic review.

Setting: Physicians, resident physicians, and medical students in North America, Asia, and Oceania.

Synopsis: Seventy-nine articles were included in the analysis, with 14 being RCTs. Most of the studies were conducted in North America (78.5%) and used a pre-post interventional design (58.2%). Practicing physicians (36.7%) made up the majority of participants in the study, with residents (15.2%) and medical students (6.3%) in smaller numbers. Analysis of the studies identified three factors for successful learning:

• effective transmission of knowledge about prices of services and general health economics, scientific evidence, and patient preferences;
• facilitation of reflective practice through feedback and/or stimulating reflection; and
• creation of a supportive environment.

Bottom line: The most-effective interventions in educating physicians, resident physicians, and medical students on high-value, cost-conscious care are effective transmission of knowledge, reflective practice, and supportive environment.

Citation: Stammen LA, Stalmeijer RE, Paternotte E, et al. Training physicians to provide high-value, cost-conscious care: a systematic review. JAMA. 2015;314(22):2384-2400.

Clinical question: What are the factors that promote education in delivering high-value, cost-conscious care?

Background: Healthcare costs are increasing, with most recent numbers showing U.S. expenditures on healthcare of more than $3 trillion, almost 18% of the gross domestic product. High-value care focuses on understanding the benefits, risks, and costs of care and promoting interventions that add value.

Study design: Systematic review.

Setting: Physicians, resident physicians, and medical students in North America, Asia, and Oceania.

Synopsis: Seventy-nine articles were included in the analysis, with 14 being RCTs. Most of the studies were conducted in North America (78.5%) and used a pre-post interventional design (58.2%). Practicing physicians (36.7%) made up the majority of participants in the study, with residents (15.2%) and medical students (6.3%) in smaller numbers. Analysis of the studies identified three factors for successful learning:

• effective transmission of knowledge about prices of services and general health economics, scientific evidence, and patient preferences;
• facilitation of reflective practice through feedback and/or stimulating reflection; and
• creation of a supportive environment.

Bottom line: The most-effective interventions in educating physicians, resident physicians, and medical students on high-value, cost-conscious care are effective transmission of knowledge, reflective practice, and supportive environment.

Citation: Stammen LA, Stalmeijer RE, Paternotte E, et al. Training physicians to provide high-value, cost-conscious care: a systematic review. JAMA. 2015;314(22):2384-2400.