(P277) EVALUATING LEFT CAROTID ARTERY PRESSURE DURING CIRCULATORY ARREST WITH UNILATERAL ANTEGRADE CEREBRAL PERFUSION

Background: Surgical intervention for aortic arch disease requires a period of circulatory arrest with cerebral perfusion to reduce the risk of neurological sequelae. Right-sided unilateral antegrade cerebral perfusion (ACP) is a common method given its shorter implementation time and avoidance of additional manipulation arch vessel manipulation. It has been shown to have equal effectiveness and outcomes compared with bilateral ACP. However, contralateral cerebral malperfusion can occur with variations in the Circle of Willis. Left carotid pressure (LCP) monitoring can be a marker of left cerebral perfusion pressures. LCP monitoring is not routine during unilateral ACP and its role is not studied extensively in the literature. Our objective was to compare the LCP with right radial artery pressure (RRP) during unilateral ACP in a cohort of patients who underwent aortic arch surgery.

METHODS AND RESULTS: A retrospective chart review was conducted from May 2022 to Feb 2024 of patients who underwent aortic arch surgeries with unilateral ACP and concurrent LCP monitoring at our institution. Patient demographics, RRP, left radial pressure, LCP, postoperative stroke, 30- and 60-day mortality were recorded. The LCPs and RRPs were compared at ACP initiation, 5, 10, and 15 minutes.
Twenty-three patients were included, with a mean age of 70 (±9.5) years and 65.2% male. None had a known history of cerebrovascular abnormalities. At ACP initiation, 7/21 patients had a >50% reduction in LCP compared with RRP. Additionally, 8/21 patients had an LCP ≤30mmHg. At five minutes of ACP, 7/23 patients had a >50% reduction in LCP compared with RRP. Three of these patients had an LCP ≤30mmHg. At 10 minutes, 5/23 patients had a >50% reduction in LCP compared with RRP. Four patients had an LCP ≤30mmHg. At 15 minutes, 5/19 patients had a >50% reduction in LCP compared with RRP, and 3 patients had an LCP ≤30mmHg. No postoperative cerebrovascular events or mortalities were recorded within 60 days.

Conclusion: Around one-third of patients had a >50% decrease in LCP compared with RRP. These results suggest that variation exists between the LCP and RRP during unilateral ACP, which could be an indicator of intracerebral perfusion pressure variation, with the contralateral side having lower perfusion pressures. This highlights the need to analyze a larger cohort to evaluate the effectiveness of unilateral ACP in preventing neurological sequelae, an important outcome for patients. Further, individual anatomic variations should be assessed with imaging and correlated with outcomes.