A regional quality improvement effort to increase beta blocker administration before vascular surgery

Abstract

Objective: To determine if a regional quality improvement effort can increase beta-blocker utilization prior to vascular surgery and decrease the incidence of postoperative myocardial infarction (POMI).

Methods: A quality improvement effort to increase perioperative beta blocker utilization was implemented in 2003 at centers participating in the Vascular Study Group of New England (VSGNE). A 90% target was set and feedback given at biannual meetings. Beta blocker utilization (<1 month preoperative versus chronic) and POMI rates were prospectively collected for patients undergoing open abdominal aortic aneurysm (AAA) repair (n = 926) and lower extremity bypass (LEB; n = 2,123) from 2003 through 2008. Predictors of POMI were determined using multivariate logistic regression. Rates of beta blocker administration and POMI were analyzed over time, and across strata of patient risk based on a multivariate model.

Results: Perioperative beta blocker treatment increased from 68% of patients in the first 3 months of 2005 to 88% by the last 3 months of 2008 (P < .001). In 2003, 44% of patients not on chronic beta blockers were treated with preoperative beta blockers; by 2008, 78% of patients not on chronic beta blockers were started perioperatively on these medications (P < .001). Beta blocker utilization increased across all centers and surgeons participating during the study period, and increased in patients of low, medium, and high cardiac risk. However, the rate of POMI did not change over time (5.2% in 2003, 5.5% in 2008; P = .876), although a trend towards lower POMI rate was seen in patients on preoperative beta blockers (4.4% in 2003-2005, 2.6% in 2006-2008; P = .43). In multivariable modeling we found that age >70 (odds ratio [OR], 2.1), positive stress test (OR, 2.2), congestive heart failure (CHF; OR, 1.7), chronic beta blocker administration (OR, 1.7), resting heart rate <70 (OR, 1.8), and diabetes (OR, 1.6) were associated with POMI. Resting heart rate was similar for patients on chronic (67), preoperative (70), and no beta blockers (70; P = .521).

Conclusions: Our regional quality improvement effort successfully increased perioperative beta blocker utilization. However, this was not associated with reduced rates of POMI or resting heart rate. While this demonstrates the effectiveness of regional quality improvement efforts in changing practice patterns, further work is necessary to more precisely identify those patients who will benefit from beta blockade at the time of vascular surgery.