A tale of 2 hospitals: a staggered cohort study of targeted interventions to improve compliance with antibiotic prophylaxis guidelines.

Abstract

The purpose of this prospective study was to determine the effectiveness of targeted interventions to improve compliance with antibiotic prophylaxis guidelines (timing, spectrum, and discontinuation) at 2 university-affiliated hospitals. Based on barriers identified previously, hospital-specific interventions were developed such as educational conferences, standardized forms, an extended time-out, and feedback. Guideline compliance and surgical site infection (SSI) data were recorded on all patients who underwent elective laparotomies for colorectal procedures, vascular operations, and hysterectomies during four 6-month study periods. Prestudy data from July to December 2006 served as a baseline. One year later, a prospective cohort study was performed. The interventions were introduced to the 2 hospitals in a staggered fashion with 2-month implementation periods before reassessing compliance during the 6-month study periods. General linear modeling was performed (P < .05 significant). Compliance with all 3 guidelines combined improved during the year preceding the study, after attention only, at both hospitals. Hospital-specific differences were found in the effectiveness of the intervention package on individual guidelines. Hospital 2 but not 1 improved in timing after the interventions; both hospitals improved in spectrum, and neither hospital improved in discontinuation. Overall compliance with all 3 antibiotic prophylactic measures was greater at hospital 1, but hospital 2 had lower SSI rates. Simply increasing attention to a quality problem can result in a significant and sustained improvement. Quality improvement interventions should be evaluated rigorously for effectiveness given hospital-specific differences in effectiveness and for correlation of guideline compliance with outcome.