The effect of hospital vascular operation capability on outcomes of lower extremity arterial bypass graft procedures

Background. The purpose of this study was to determine whether hospitals with a high capability for vascular operations have lower rates of inpatient mortality, major complication, and major amputation with lower extremity arterial bypass (LEAB) procedures than do less well-equipped hospitals after controlling for hospital procedure volume and patient characteristics. Methods. Admissions of 16, 422 northern Illinois residents to Illinois hospitals for aortoiliac (AI) or distal bypass operations during 1993 to 1999 were analyzed. Hospitals were considered to have a high capability for vascular operations if they had cardiac surgical facilities and either an accredited blood flow laboratory, general surgical residency, or fellowship training in vascular surgery. Logistic regression was used to model the effect of hospital capability on mortality after controlling for hospital LEAB procedure volume, operation level, severity of illness, age, sex, and emergent admission. Results. Sixteen of 98 Illinois hospitals with 34.4% of the sample patients, including 8 of 18 hospitals with more than 40 admissions for LEAB procedures annually, were classified as having high surgical capability. Hospitals classified as having high versus low capability had lower mortality (2.8% vs 3.7%; P = .003) and amputation rates (4.6% vs 4.9% [not significant]) but higher major complication rates (9.8% vs 8.5%; P = .006). Conclusions. Mortality outcomes for LEAB procedures were superior at high capability hospitals, even after controlling for patient characteristics, disease severity, and LEAB volume. Hospital complication rates were not correlated with mortality rates and may not be a meaningful measure of quality of care.