Objective Cerebral oximetry (COXI) complements online monitoring of cerebral oxygenation during aortic arch surgery. Its addition targets at an increase of safety of a complex procedure employing unilateral antegrade cerebral perfusion (UACP) and circulatory arrest under tepid blood temperatures. We report the outcome of Cerebral oximetry-guided aortic arch surgery using UACP with moderate hypothermic circulatory arrest (MHCA).
Methods Between December 2011 and December 2012, COXI was used in 36 patients (mean age: 57.5 – 11.3 years) undergoing aortic arch repair using UACP combined with MHCA. The diagnosis was atherosclerotic thoracic aneurysms in twenty-eight and acute aortic dissection in eight patients. Seven patients had a hemi-arch replacement, and four patients had concomitant procedures such as coronary artery bypass grafting (CABG) or aortic valve surgery. Our regimen of employing an algorithm for adaptation of perfusion modalities included the threshold of the drop in regional cerebral oxygen saturation < 55% and/or a drop in the total oxygen index (TOI).
Results The mean MHCA was 32 ± 16 min and lowest rectal temperature was 26 – 1.2 8 C. The mean TOI pre-MHCA was 66 – 6.5%. Five out of 36 patients underwent bilateral perfusion because of unilateral drops below the threshold level of TOI (mean: 43 – 5.9%). In three patients, an organic psychosyndrome was observed. No patient developed permanent neurological dysfunction.
Conclusions Cerebral oximetry-guided UACP during MHCA allows a safe approach to complex aortic arch surgery. The drop of brain oxygenation values in the contralateral hemisphere during BACP strongly suggests the routine use of UACP, when circulatory arrest under tepid temperatures is used.