Efficiency of Various Cerebral Protection Techniques Used during the Surgical Treatment of Chronic Pulmonary Thromboembolism.

Circulatory arrest during pulmonary thromboendarterectomy (PTE) for chronic pulmonary embolism leads to an increased risk of cerebral ischemia and neurological complications. This study aimed to assess the efficacy of various cerebral protection techniques used during the surgical treatment of chronic pulmonary thromboembolism. We prospectively studied 61 patients with chronic pulmonary thromboembolism who underwent PTE. We compared the dynamics of cerebral oxygen saturation (rSO2, %) during the surgical treatment and analyzed neurological complications during the early postoperative period in two groups of patients: 30 patients who underwent surgery under conditions of moderate hypothermia (23°C-24°C) combined with antegrade unilateral cerebral perfusion (ACP group) and 31 patients who underwent thromboendarterectomy under deep hypothermic circulatory arrest (18°C, DHCA group) combined with craniocerebral hypothermia. In the ACP group, regional rSO2 decreased by less than 20% from baseline during the course of PTE. In the DHCA group, a more profound reduction of cerebral oxygen supply (by >30% from baseline) was recorded compared with the ACP group (p < .05). During the early postoperative period, 29% of patients in the DHCA group exhibited neurological complications, compared with only 7% of patients from the ACP group. The results of logistic regression analysis indicated that the risk of progressive neurological deficit depended on the duration of the intraoperative period when the absolute values of regional rSO2 were <40%. The method with the best adjustment to human physiology in patients with chronic pulmonary thromboembolism was antegrade cerebral perfusion. This method provides a smaller decrease in cerebral oxygen supply during thromboendarterectomy and significantly reduces the risk of ischemia and neurological complications in the early postoperative period.