In the Literature: HM-Related Research You Need to Know
Literature at a Glance
A guide to this month’s studies
- Risks of preoperative tobacco use
- Timing of perioperative beta-blocker use and outcomes
- Continuous vs. bolus dose diuretics in CHF
- Outcomes of carotid endearterectomy and carotid artery stenting
- Protocol for low-risk chest pain
- Effect of esomeprazole on recurrent ulcer rates in clopidogrel users
- Effect of ICU QI project on hospital mortality
- Acute kidney injury risks after coronary angiography
Smokers Have Worse Perioperative Outcomes
Clinical question: Do current smokers have worse 30-day postoperative outcomes than nonsmokers after noncardiac surgery?
Background: Approximately 20% of adults in the U.S. smoke cigarettes, and a significant fraction of surgical patients are current smokers. Despite concerns that smoking is associated with worse postoperative outcomes, these increased risks have not been quantified across multiple outcomes.
Study design: Retrospective cohort study.
Setting: Surgical patients in 200 centers throughout the United States.
Synopsis: Data from the American College of Surgeons National Surgical Quality Improvement Program from 2005 to 2008 were acquired, and 391,006 patient records were reviewed. Postoperative morbidity and mortality were significantly greater in smokers. Current smokers had a 40% increased odds of death at 30 days compared to people who had never smoked (OR 1.38, 95% CI, 1.11-1.72). Current smokers also had significantly greater odds of pulmonary complications, including pneumonia (OR 2.09, 95% CI, 1.80-2.43), unplanned intubation (OR 1.87, 95% CI, 1.58-2.21), and mechanical ventilation (OR 1.53, 95% CI, 1.31-1.79).
Furthermore, current smokers had significantly greater odds of postoperative cardiac arrest (OR 1.57, 95% CI, 1.10-2.25), myocardial infarction (OR 1.80, 95% CI, 1.11-2.25), and stroke (OR 1.73, 95% CI, 1.18-2.53). Odds of infectious complications were increased in current smokers, including deep incisional infections (OR 1.42, 95% CI, 1.21-1.68), sepsis (OR 1.30, 95% CI, 1.20-1.60), and septic shock (OR 1.55, 95% CI, 1.29-1.87).
Limitations of this study include self-reporting of smoking habits and absence of detailed smoking history just before and after surgery.
Bottom line: Current smokers have significantly increased postoperative morbidity and mortality after noncardiac surgery.
Citation: Turan A, Mascha EJ, Roberman D, et al. Smoking and perioperative outcomes. Anesthesiology. 2011;114(4):837-846.
Chronic Beta-Blockade Reduces Postoperative Myocardial Ischemia
Clinical question: Does the timing of beta-blocker exposure affect cardiovascular outcomes in patients undergoing elective, noncardiac surgery?
Background: Several studies have demonstrated that beta-blockers are associated with decreased perioperative cardiovascular morbidity and mortality. Study designs have varied greatly, and differences in dosing and timing of beta-blocker administration have caused conflicting results. The question of when to initiate beta-blockers prior to surgery remains controversial.
Study design: Prospective cohort study.
Setting: Three academic medical centers in Canada.
Synopsis: Data from 1,398 patients who had elective, noncardiac surgery with either acute (n=436) or chronic (n=962) beta-blocker exposure were analyzed. Acute exposure was defined as receiving a beta-blocker for the first time within 48 hours after surgery, whereas chronic beta-blocker exposure was defined as receiving a beta-blocker seven to 10 days prior to surgery.
Patients with chronic beta-blocker exposure were more likely to have a history of coronary disease, heart failure, or hypertension and were more likely to be receiving statins, antiplatelet agents, and angiotensin-converting enzyme inhibitors. The primary outcome was a composite of major cardiac events, including myocardial infarction, nonfatal cardiac arrest, and 30-day mortality.
