Original Article

Evaluation of Hemodynamic and Regional Tissue Perfusion Effects of Minimized Extracorporeal Circulation (MECC®)

^* Department of Cardiovascular Technology, MediClin Heart Centre Coswig, Sachsen Anhalt, Germany
^† Department of Cardiothoracic and Vascular Surgery, University Hospital of Regensburg, Regensburg, Germany
^‡ Department of Cardiovascular Surgery, MediClin Heart Centre Coswig, Sachsen Anhalt, Germany
^§ Department of Cardio - Anesthesiology, MediClin Heart Centre Coswig, Sachsen Anhalt, Germany

Address correspondence to: Adrian Bauer, ECCP, MCVT, Chief Perfusionist, Department of Cardiovascular Technology, MediClin Heart Center Coswig, Lerchenfeld 1, 06869 Coswig, Sachsen-Anhalt, Germany. E-mail: baueradrian@msn.com

Received: 2 March 2009
Accepted: 15 February 2010

Abstract

Minimized extracorporeal circulation (MECC®, Maquet, Cardiopulmonary AG, Hirrlingen, Germany) is an established procedure to perform coronary revascularization. Studies showed positive effects of MECC compared to conventional cardiopulmonary bypass (CCPB) procedures in terms of transfusion requirements, less inflammation reactions, and neurological impairments. Recent retrospective studies showed higher mean arterial pressure (MAP) and a lower frequency of vasoactive drug use. We addressed this issue in this study. The hypothesis was to find a higher MAP during coronary bypass grafting surgery in patients treated with MECC systems. We performed a prospective, controlled, randomized trial with 40 patients either assigned to MECC (n = 18) or CCPB (n = 22) undergoing coronary bypass grafting. Primary endpoints were the perioperative course of mean arterial pressure, and the consumption of norepinephrine. Secondary endpoints were the regional cerebral and renal oxygen saturation (rSO₂) as an indicator of area perfusion and the course of hematocrit. Clinical and demographic characteristics did not significantly differ between both groups. Thirty-day mortality was 0%. At four of five time points during extracorporeal circulation (ECC) MAP values were significantly higher in the MECC group compared to CCPB patients (after starting the ECC 60 ± 11 mmHg vs. 49 ± 10 mmHg, p = .002). MECC patients received significantly less norepinephrine (MECC 22.5 ± 35 μg vs. CCPB 60.5 ± 75 μg, p = .045). The rSO₂ measured at right and left forehead and the renal area was similar for both groups during ECC and significantly higher at CCPB group 1 and 4 hours after termination of CPB. Minimized extracorporeal circulation provides a higher mean arterial pressure during ECC and we found a lower consumption of vasoactive drugs in the MECC group. There was a decrease in regional tissue saturation at 1 and 4 hours post bypass in the MECC group possibly due to increased systemic inflammation and extravascular fluid shift in the CCPB group.