Safety and limitations of line pressure-targeted cerebral perfusion strategy in aortic arch surgery

The optimal flow rate for selective antegrade cerebral perfusion during aortic arch surgery is unknown. While 10-15 ml/kg/min is generally recommended, our centre has adopted a line pressure-targeted, relatively low-flow antegrade cerebral perfusion strategy. We aimed to evaluate the effect of flow rate on neurological outcomes.

Patients without preoperative neurological deficits who underwent aortic arch surgery between January 2018 and May 2023 were enrolled. Under moderate hypothermia, an initial cerebral ischaemia period of 15-20 min was permitted. Following a brief retrograde cerebral perfusion, bilateral selective antegrade cerebral perfusion was performed using balloon-tipped perfusion catheters. The flow rate was determined using a line pressure of 200 mmHg. Risk factor analysis for postoperative permanent and temporary neurological deficits was conducted.

A total of 262 patients were included. The median selective antegrade cerebral perfusion flow rate was 5.7 ml/kg/min. Permanent neurological deficits occurred in 2 patients (0.8%), while temporary neurological deficits occurred in 30 patients (11.5%). The low antegrade cerebral perfusion flow rate was not a risk factor for permanent or temporary neurological deficits. Prolonged cerebral ischaemia time was the only significant risk factor for temporary neurological deficits.

Under moderate hypothermia and with the assistance of retrograde cerebral perfusion, the line pressure-targeted, relatively low-flow selective antegrade cerebral perfusion strategy at our centre achieved favourable neurological outcomes. However, prolonged cerebral ischaemia time was a significant risk factor for temporary neurological deficits.