Arterial hypotension "magnitude" and neurological outcome during mechanical thrombectomy under general anesthesia.

Introduction: Mechanical thrombectomy (MT) is the standard of care for the treatment of acute ischemic stroke (AIS) with large vessel occlusion (LVO), but unfavorable outcomes remain common. Procedural arterial hypotension is associated with poor patient outcome. This study aimed to assess the impact of arterial hypotension "magnitude" (a combination of the depth, defined as the percentage relative to baseline arterial blood pressure, and the duration of hypotensive episodes)" during MT on neurological outcome.

Methods: This is a monocentric retrospective study. Charts were reviewed between January 2018 and June 2021. "Patients were eligible if they were 18 years or older, anterior LVO was diagnosed on cerebral imaging" and MT performed under general anesthesia. Mean arterial pressure (MAP) was recorded every 5 min throughout the procedure, and the arterial hypotension "magnitude" was estimated by the area under the curve (AUC) for different thresholds of MAP drops.

Main Outcome Measure: The modified Rankin Scale (mRS) at 90 days.

Main Results: Among the 117 patients analyzed, 46% had poor neurological outcome. Our study showed correlations between poor outcome and a greater procedural AUC of arterial hypotension for the different thresholds: 5% (k 0.18; 95% CI 0.06-0.30; P = 0.007), 10% (k 0.18; 95% CI 0.05-0.30; P = 0.008), 15% (k 0.18; 95% CI 0.04-0.30; P = 0.011), 20% (k 0.18; 95% CI 0.05-0.30; P = 0.010) and 30% (k 0.19; 95% CI 0.05-0.31; P = 0.010). This association persisted after controlling for age, baseline NIHSS score, and ASPECT score.

Conclusion: The magnitude of hypotension during MT under general anesthesia for AIS is an independent factor of poor outcome at 90 days. These associations have been observed in patients with mild and severe hypotensive episodes.