Randomized Trial of Pulsatile and Nonpulsatile Flow in Cyanotic and Acyanotic Congenital Heart Surgery

BackgroundThe study objective was to determine the impact of cardiopulmonary bypass perfusion modalities on cerebral hemodynamics and clinical outcomes in congenital cardiac surgery patients stratified by acyanotic versus cyanotic heart disease.MethodsA total of 159 pediatric (age <18 years) cardiac surgery patients were prospectively randomized to pulsatile or nonpulsatile cardiopulmonary bypass and stratified by type of congenital heart disease: acyanotic versus cyanotic. Intraoperative cerebral gaseous microemboli counts and middle cerebral artery pulsatility index were assessed. Organ injury was quantified by Pediatric Logistic Organ Dysfunction-2 (PELOD-2) score at 24, 48, and 72 h postoperatively. Additional outcomes included Pediatric Risk of Mortality-3 score, vasoactive-inotropic score, duration of mechanical ventilation, intensive care and hospital length of stay, and 180-day mortality. Heterogenous variance linear models (ie, ANOVA and mixed models) and χ² tests were used to compare groups for continuous and categorical variables, respectively.ResultsWithin congenital heart disease subgroups, patients randomized to nonpulsatile versus pulsatile bypass had similar preoperative and operative characteristics. While the intraoperative pulsatility index was higher in the pulsatile subset of both acyanotic and cyanotic groups (P < .05), regional cerebral oxygen saturation, mean arterial pressure, and gaseous microemboli counts were similar. Postoperative PELOD-2 scores decreased at similar rates in the acyanotic and cyanotic subgroups regardless of the perfusion modality utilized. There were also no significant between-group differences in the additional postoperative outcomes by perfusion modality in either acyanotic or cyanotic groups.ConclusionsDespite patients undergoing pulsatile cardiopulmonary bypass experiencing a more physiologic pulsatility index in both acyanotic and cyanotic groups, no significant differences in cerebral hemodynamics or clinical outcomes were appreciated.