This Month in Anesthesiology

Abstract

In this observational study, investigators measured the prevalence of preoperative anemia in noncardiac surgery patients and assessed the relationship between preoperative anemia and postoperative mortality. Data were retrospectively collected on 7,759 consecutive noncardiac surgical patients between 2003 and 2006. The relationship between preoperative anemia and postoperative mortality was assessed using logistic regression and propensity analyses. Preoperative anemia was common and equal between genders. After adjustment for major confounders, anemia was associated with increased mortality (odds ratio = 2.36, 95% confidence interval = 1.57–3.41). The authors propose that treatment of preoperative anemia should be the focus of investigations for the reduction of perioperative risk.Investigators sought to identify the incidence, risk factors, and mortality impact of acute kidney injury (AKI) after general surgery using a national clinical dataset. The primary outcome was AKI within 30 days after surgery. The authors identified 11 independent preoperative predictors: age greater than or equal to 56 yr, male gender, emergency surgery, intraperitoneal surgery, diabetes mellitus requiring oral therapy, diabetes mellitus requiring insulin therapy, active congestive heart failure, ascites, hypertension, mild preoperative renal insufficiency, and moderate preoperative renal insufficiency. From these data, the authors developed a risk index that is predictive of AKI after general surgery so that trials attempting to reduce this risk can be conducted. See the accompanying Editorial View on page 449 Surgical site infections (SSIs) increase morbidity, mortality, length of hospital stay, and costs. The authors sought to identify modifiable risk factors associated with SSI after spinal surgery. Medical records from 104 patients with SSI were compared with 104 randomly selected control patients without SSI. Multivariate analysis identified independent risk factors for SSI including prolonged procedure duration, American Society of Anesthesiologists score of 3 or greater, lumbar-sacral operative level, posterior approach, instrumentation, obesity, razor shaving before surgery, and intraoperative inspired oxygen concentration of less than 50%. The authors propose that administration of at least 50% inspired oxygen should be tested prospectively as an intervention to prevent SSI after spinal surgery.The clinical safety and outcome of intensive insulin therapy compared with conventional insulin therapy was investigated in patients receiving postoperative intensive care after brain surgery. Four hundred and eighty three patients were prospectively and randomly assigned either to intensive insulin therapy or to conventional insulin therapy. Median hypoglycemic episodes were more frequent in patients receiving intensive insulin therapy (8 vs. 3). However, the length of stay in the intensive care unit (ICU) was shorter (6 vs. 8 days) and the infection rate was less (25.7% vs. 39.3%). Glasgow outcome scale score and overall survival at 6 months were similar. This study showed intensive insulin therapy in neurosurgical ICU patients after brain surgery is associated with iatrogenic hypoglycemia but appears to decrease infection rate and ICU stay. See the accompanying Editorial View on page 456 This Practice Advisory focuses on magnetic resonance imaging settings where anesthetic care is provided.The Functional Recovery Index questionnaire will be a good instrument for assessing recovery of ambulatory surgical patients.Challenges in informed consent influence anesthesiologists' views of current and future patients, their practice, their profession, and themselves. See the accompanying Editorial View on page 445 Current concepts on the pathogenesis of ventilator-associated pneumonia in relation to the endotracheal tube are reviewed.