Clinical question: In patients undergoing noncardiac surgery, what is the incidence and clinical characteristics of perioperative myocardial infarction (MI)?
Background: Though millions of patients experience perioperative MI after noncardiac surgery, little is known about the characteristics and outcomes of these patients.
Study design: Cohort study.
Setting: One hundred ninety centers in 23 countries.
Synopsis: Using data from the 8,351 patients in the POISE (PeriOperative ISchemic Evaluation) trial, this study showed that perioperative MI occurred in 5% of patients; 65% were asymptomatic. Patients who experienced postoperative MI were older and had more cardiovascular risk factors when compared to those who did not. The 30-day mortality was higher in patients with a perioperative MI (11.6%) compared with those who did not (2.2%); the presence or absence of ischemic symptoms was not associated with mortality rate.
Of the 8.3% of patients who experienced an elevation in cardiac biomarkers but who did not meet the definition of MI, there was an increased risk of nonfatal cardiac arrest and nonacute coronary revascularization. Those in the highest quartile also had increased 30-day mortality.
Bottom line: Given the high proportion of asymptomatic MIs and isolated elevations in cardiac biomarkers and the association between these events and increased risk of death, hospitalists should consider routine monitoring of troponin in at-risk patients undergoing noncardiac surgery.
Citation: Devereaux PJ, Xavier D, Pogue J, et al. Characteristics and short-term prognosis of perioperative myocardial infarction in patients undergoing noncardiac surgery: a cohort study. Ann Intern Med. 2011;154(8):523-528.
Patients Prescribed Higher Opioid Doses Are at Increased Risk of Opioid Overdose Death
Clinical question: What is the association between opioid prescribing patterns and fatal opioid overdose?
Background: In the past 10 years, the rate of fatal overdose from opioid prescription for pain has more than doubled. Little is known about how the indications (substance abuse disorders, cancer-related pain, chronic pain, acute pain), maximal daily dose, and scheduling (standing, as-needed, or both) of opioid prescriptions relate to this increased risk.
Study design: Case-cohort study.
Setting: Veterans Health Administration (VHA) patients.
Synopsis: The VHA’s National Patient Care Database was used to randomly select a cohort of 154,684 nonhospice/nonpalliative-care patients who were prescribed opioids from 2004 to 2008. They were compared with 750 patients who were treated with prescription opioids who died from opioid overdose during this time.
Fatal opioid overdose was a rare event (0.04%), but risk increased with higher prescribed maximum daily morphine dose-equivalence, especially when greater than or equal to 50 mg/day in all subgroups (substance abuse, acute and chronic pain, and cancer). Fatal overdoses were higher in middle-aged white men with acute or chronic pain, substance abuse disorders, and other psychiatric illness. Patients with cancer were at increased risk of fatal overdose if they were prescribed as-needed opioids alone.
Treatment with both as-needed and standing opioids did not statistically affect risk of overdose death in any subgroup.
Bottom line: Although rare, risk of fatal opioid overdose in patients prescribed opiate medication increases with higher maximum prescribed daily dose.
Citation: Bohnert AS, Valenstein M, Bair M, et al. Association between opioid prescribing patterns and opioid overdose-related deaths. JAMA. 2011; 305:1315-1321.
Structured Interdisciplinary Rounds on Medical Teaching Unit Significantly Decrease Adverse Events
Clinical question: Do structured interdisciplinary rounds have an impact on the rate of adverse events?
Background: Many preventable adverse events occurring during hospitalization can be attributed to communication failures. Structured interdisciplinary rounds provide a format as well as a forum for team members to discuss patient care. Prior studies demonstrated improvements in collaboration; whether this translates to better patient care is not known.