Comparing clinical outcomes in high-volume and low-volume off-pump coronary bypass operation programs

Background. A growing body of data suggests that physicians or medical cent ers performing a higher volume of patient services achieve better outcomes. We hypothesized that an important dimension of coronary artery bypass graf t (CABG) volume is the cardiovascular surgical team experience with perform ing off-pump coronary artery bypass (OPCAB) procedures, as well as the team 's ability to provide the optimal approach for the patient's clinical condi tion. Teams performing 100 or more OPCAB operations have improved clinical decision-making processes and technical skills regarding treatment of all C ABG patients, regardless of whether cardiopulmonary bypass is used. We hypo thesized that this experience and choice of approaches for CABG procedures translates into better clinical outcomes. Methods. Using data on 16,988 consecutive patients in 72 hospitals from the HCA-The Healthcare Coe OPCAB sites and then analyzed the patient and hospi tal characteristics that had an impact on clinical outcomes. Results. The mortality rates for the high- and low-volume OPCAB facilities both averaged 2.9% (p = NS). Patients at the high-volume OPCAB facilities h ad significantly lower rates of major complications (shock/hemorrhage, neur ologic, renal, and cardiac) than those at the low-volume OPCAB facilities. Of the seven minor complications, rates for six were lower in the high-volu me OPCAB facilities, but none of the differences reached statistical signif icance. High-volume OPCAB sites were significantly more likely to discharge their patients directly home than were low-volume OPCAB sites (80% versus 66%; P = 0.001). Conclusions. The results suggested that surgical team experience and choice of approaches to performing CABG had an impact on patient outcomes. (C) 20 01 by The Society of Thoracic Surgeons.