Colder is better during hypothermic circulatory arrest for acute type A aortic dissection.

OBJECTIVES: To evaluate the influence, on early postoperative outcomes, of temperature during hypothermic circulatory arrest in emergent surgery for acute type A aortic dissection. DESIGN: Hypothermic circulatory arrest (HCA) with antegrade cerebral perfusion was performed in 63 patients who underwent emergent surgery for acute type A aortic dissection between 2000 and 2009. Patients were retrospectively separated in two groups: ( 1 ) deep HCA, lowest nasopharyngeal temperature < 17 °C (n = 29; 46%) and ( 2 ) moderate HCA, lowest nasopharyngeal temperature ≥ 17 °C (n = 34; 54%). RESULTS: Hospital mortality reached 27%. The nasopharyngeal temperature did not influence postoperative mortality or neurological outcome. Patients with deep HCA had significantly lower rate of infection (33% vs. 69%; p = 0.009) and shorter median intensive care unit length of stay (4 days ( 17 ) vs. 15.5 days ( 26 ) p = 0.017). Multiple regression analysis revealed that the lowest nasopharyngeal temperature was the only significant variable associated with intensive care unit length of stay (p = 0.005). CONCLUSIONS: Patients suffering from acute type A aortic dissection might benefit from colder hypothermia during circulatory arrest.