Should we discontinue intraaortic balloon during cardioplegic arrest? Splanchnic function results of a prospective randomized trial

Background. Preoperative use of intraaortic ballon pumping (IABP) has increased in high-risk patients. Linear flow during cardiopulmonary bypass (CPB) can induce subclinical damage, whereas automatic IABP mode may maintain pulsatile flow. We sought to evaluate differences between suspending IABP and switching it to an automatic 80 bpm mode during cardioplegic arrest.Methods. Between January and November 2004, 40 patients undergoing preoperative IABP were randomized to receive either standard nonpulsatile CPB with IABP discontinued during cardioplegic arrest (20 patients; group A) or IABP-induced pulsatile (automatic 80 bpm) CPB (20 patients; group B). Hospital outcome was recorded. Urine output, blood urea nitrogen (BUN), creatine, creatinine clearance, peripheral lactate, recovery of gut motility, alanine-amino-transf erase (ALT), aspartateamino-transferase (AST), lactic dehydrogertase (LDH), bilirubin, and amylase (AMY) were compared.Results. There were no IABP-related complications, nor perioperative renal or liver failures, nor hospital deaths, nor myocardial infarctions. Intensive care and hospital stay, urine output, and recovery of gut motility were comparable. Group B showed lower creatine on the first (P = 0.01) and second (p = 0.005) postoperative days, higher creatinine clearance (first day: p = 0.01; second day: p = 0.03), lower lactate after CPB termination (p = 0.0001) and during the first day (p = 0.001). The ALT, AST, and AMY were lower in group B (first day ALT: p = 0.01; AST: p = 0.04; AMY: p = 0.017; second day ALT: p = 0.01; AST: p = 0.02; AMY: p = 0.027), as well as total bilirubin (first day: p = 0.05; second day: p = 0.02).Conclusions. Automatic 80 bpm IABP during cardioplegic arrest improves creatinine clearance and splanchnic enzymes. There is no reason to suspend preoperative IABP support during cardioplegic arrest.