Whole body perfusion strategy for aortic arch repair under moderate hypothermia

Introduction: Aortic arch reconstruction under moderate hypothermia is commonly performed with antegrade cerebral perfusion (ACP) for brain protection; however, hypothermia alone is often solely relied upon for visceral and lower body protection. We investigated whether the addition of simultaneous lower body perfusion to ACP (whole body perfusion - WBP) may ameliorate the metabolic derangements of moderate hypothermic circulatory arrest (MHCA). Methods: Between 2008 and 2014, 106 consecutive patients underwent elective or emergent aortic arch surgery with MHCA, with either ACP only (44 patients, 66±12 years, 30% female) or WBP (62 patients, 61±15 years, 31% female). Primary outcomes included 30-day/in-hospital mortality, intensive care unit (ICU) and hospital lengths of stay (LOS) and specific parameters of metabolic recovery. Results: There were no significant differences between the groups in 30-day/in-hospital mortality (ACP: 3 (6.8%), WBP: 2 (3.2%); p=0.65), stroke (ACP: 1 (2.3%), WBP: 1 (1.6%); p=1.0) or renal failure (ACP: 2 (4.5%), WBP: 1 (1.5%); p=0.57). In the WBP group, we identified a significant reduction in lactate level at ICU admission (ACP 5.5 vs. WBP 3.5 mmol/L; p=0.002), time to lactate normalization (p=0.014) and median ICU length-of-stay (ACP 3 vs. WBP 1 days; p=0.049). There was no difference in post-operative creatinine (ACP: 104, WBP: 107 μmol/L; p=0.66). After multivariable regression adjustment, perfusion strategy no longer remained an independent predictor of ICU discharge time (p=0.09), however, cardiopulmonary bypass time (p=0.02), age (p=0.012) and emergent surgery (p=0.02) were. Conclusions: A WBP strategy during aortic arch reconstruction with MHCA may be associated with more rapid normalization of metabolic parameters and reduced ICU length of stay compared to using ACP alone. Further evaluation with a randomized trial is warranted.