Evidence-Based Referral Results in Significantly Reduced Mortality After Congenital Heart Surgery

Abstract

Objective. Significant interinstitutional variation in mortality after congenital heart surgery has been demonstrated. Noting an association between reduced mortality and higher volume, a center with a small annual case volume began in August 1998 to selectively refer to high-volume surgical centers based on published or “apparent” low mortality rates for specific cardiac lesions. This study was undertaken to evaluate the effect of evidence-based referral in this practice. Design, Setting, and Participants. A retrospective cohort comparison over a 10-year period for a small Midwestern pediatric cardiology practice. The institutional database was retrospectively reviewed for children (Results. A total of 514 congenital heart surgical cases were identified from August 1992 to July 2002; 507 cases (98.6%) were assigned to a risk category and analyzed further. Unadjusted in-hospital mortality rates were 9.3% in period 1, 5.9% in period 2, and 1.3% in period 3. Unadjusted mortality rates for cases from benchmark data were 6.4% in 1992, 4.8% in 1996, and 3.7% in 1998. Risk adjusted mortality was comparable to the benchmark data in periods 1 and 2, but superior outcomes (odds ratio = 0.24) were demonstrated in period 3. Conclusions. Evidence-based referrals from a small-volume pediatric cardiac center to large-volume institutions resulted in a reduction in mortality after congenital heart surgery.