A further evaluation of intraoperative parameters of high-risk patients experiencing a CAE showed that these patients were more likely to have an episode of mean arterial pressure (MAP) <50 mmHg, an episode of 40% decrease in MAP, and an episode of tachycardia (heart rate >100).
Bottom line: A combination of preoperative predictors and intraoperative elements can help improve risk assessment for perioperative CAEs after noncardiac surgery.
Citation: Kheterpal S, O’Reilly M, Englesbe M, et al. Preoperative and intraoperative predictors of cardiac adverse events after general, vascular, and urological surgery. Anesthesiology. 2009;110(1):58-66.
Clinical question: Will implementing evidence-based feeding guidelines improve feeding practices and reduce mortality in ICU patients?
Background: There is evidence suggesting that providing nutritional support to ICU patients within 24 hours of admission may decrease mortality. It is widely understood that patient care varies between ICUs, and there exist no uniform, evidence-based guidelines for nutritional support. Many patients remain unfed after 48 hours.
Study design: Cluster, randomized-controlled trial.
Setting: ICUs in 27 community and tertiary-care hospitals in Australia and New Zealand.
Synopsis: Hospitals were randomized to intervention or control groups. Dietitian and intensivist co-investigators from intervention ICUs developed guidelines using the Clinical Practice Guideline Development Cycle. Control ICUs were requested to make no new ICU nutritional management changes. The study enrolled 1,118 eligible patients and included adults expected to stay longer than two days. Excluded were patients taking oral diets, patients receiving palliative care or with suspected brain death, and patients sent from other facilities.
Guidelines were implemented using several methods—educational outreach visits, one-on-one conversations, active reminders, passive reminders, and educational in-services. The guidelines were successful in evoking significant practice changes in all of the intervention ICUs. Significantly more patients received nutritional support during their ICU stays in guideline ICUs, and patients in these ICUs were fed significantly earlier. There were, however, no significant differences between guideline and control ICUs with regard to hospital discharge mortality (28.9% vs. 27.4%; 95% CI; -6.3% to 12.0%; P=0.75). The groups also showed no statistical difference in hospital or ICU length of stay.
Bottom line: Significantly more patients in the guideline ICUs were fed within 24 hours, but this did not translate into improvements in mortality or other clinical outcomes.
Citation: Doig G, Simpson F, Finfer S, et al. Effect of evidence-based feeding guidelines on mortality of critically ill adults: a cluster randomized controlled trial. JAMA. 2008;300(23):2731-2741.
Clinical question: Is low-dose aspirin effective for the primary prevention of atherosclerotic events in patients with Type 2 diabetes?
Background: Diabetes is a significant risk factor for cardiovascular events. Several prior studies have shown that aspirin therapy is effective as a secondary prevention strategy for cardiovascular events. The American Diabetes Association also recommends use of aspirin as a primary prevention strategy. Clinical trial data is currently insufficient in this area.
Study design: Prospective, randomized, open-label, controlled trial with blinded endpoint assessment.
Setting: 163 institutions in Japan.
Synopsis: The study enrolled 2,539 diabetic patients between 30 and 85 years old—mean age was 65—and included patients without EKG changes or a significant history or ongoing treatment of atherosclerotic disease. Patients were randomly assigned into an aspirin group (81 mg or 100 mg once daily) or a nonaspirin group. Patients had a median follow up of 4.37 years.
The primary endpoint was any atherosclerotic event, ranging from sudden death to ischemic heart disease or stroke. The incidence of atherosclerotic events was not statistically different in the aspirin group (68 events, 5.4%) than in the nonaspirin group (86 events, 6.7%) (HR, 0.80; 95% CI; 0.58-1.10; log-rank test, P=0.16). However, there was a suggested benefit of primary prevention in the subgroup aged 65 years or older. In addition, the combined endpoint of fatal coronary and cerebrovascular events occurred in one patient in the aspirin group and 10 patients in the nonaspirin group (HR, 0.10; 95 % CI, 0.01-0.79; P=.0037). This study is limited by the low incidence of atherosclerotic disease in Japan.