Prolonged Duration of Blood Pressure Drops During General Anesthesia Is Associated With Worse Outcomes After Mechanical Thrombectomy

The influence of pre-reperfusion blood pressure on outcomes following mechanical thrombectomy for anterior circulation large vessel occlusion

BACKGROUND

We evaluated how systolic blood pressure (SBP) and mean arterial pressure (MAP) parameters between presentation and reperfusion influence functional status and intracranial hemorrhage (ICH).

METHODS

All patients who underwent MT for LVO at a single institution were reviewed. Independent variables included SBP and MAP measurements obtained on presentation, between presentation and reperfusion (pre-reperfusion), and between groin puncture and reperfusion (thrombectomy). Mean, minimum, maximum, and standard deviations (SD) for SBP and MAP were calculated. Outcomes included 90-day favorable functional status, radiographic ICH (rICH), and symptomatic ICH (sICH).

RESULTS

305 patients were included. Higher pre-reperfusion SBP_max was associated with rICH (OR 1.41, 95% CI 1.08-1.85) and sICH (OR 1.84, 95% CI 1.26-2.72). Higher SBP_SD was also associated with rICH (OR 1.38, 95% CI 1.06-1.81) and sICH (OR 1.59, 95% CI 1.12-2.26). Greater SBP_max (OR 0.64, 95% CI 0.47-0.86), MAP_max (OR 0.72, 95% CI 0.52-0.97), SBP_SD (OR 0.63, 95% CI 0.46-0.86), and MAP_SD (0.63, 95% CI 0.45-0.84) during thrombectomy were associated with lower odds of 90-day favorable functional status. In a subgroup analysis, these associations were primarily limited to patients with intact collateral circulation. Optimal SBP_max cutoffs for predicting rICH were 171 (pre-reperfusion) and 179 mmHg (thrombectomy). Cutoffs for predicting sICH were 178 (pre-reperfusion) and 174 mmHg (thrombectomy).

CONCLUSION

Greater maximum BP and variability in BP during the pre-reperfusion period are associated with unfavorable functional status and ICH after MT for anterior circulation LVO.

Increased blood pressure variability during general anaesthesia is associated with worse outcomes after mechanical thrombectomy: a prospective observational cohort study

OBJECTIVES

Optimal periprocedural blood pressure (BP) management during mechanical thrombectomy (MT) for acute ischaemic stroke is still controversial. The aim of this study was to investigate the association between intraprocedural BP variability (BPV) and outcomes in patients with large vessel occlusion (LVO) following MT with general anaesthesia.

DESIGN

A prospective observational cohort study.

SETTING

This study was conducted in a single tertiary hospital of Hangzhou in Zhejiang province.

PARTICIPANTS

A total of 141 patients with LVO treated with MT were finally included between January 2018 and September 2020.

MAIN OUTCOME MEASURES

Intraprocedural BP was recorded every 5 min throughout the procedure. BPV was measured as SD, coefficient of variation (CV), max-min (RANGE) and successive variation. Haemorrhagic transformation was assessed on 24-hour CT images according to European Cooperative Acute Stroke Study III trial. Poor functional outcome was defined as 90-day modified Rankin Scale score 3-6. Binary logistic regression analysis was used to investigate the association of BPV parameters with the incidence of parenchymal haemorrhage (PH) and poor functional outcome.

RESULTS

After controlling for age, female, history of smoking, hypertension and atrial fibrillation, baseline National Institutes of Health Stroke Scale, baseline systolic BP (SBP), baseline Alberta Stroke Program Early CT Score, bridging thrombolysis and times of retrieval attempts, the results demonstrated that intraprocedural SBP_RANGE (OR 1.029; 95% CI 1.003 to 1.055; p=0.027), SBP_SD (OR 1.135; 95% CI 1.023 to 1.259; p=0.017) and SBP_CV (OR 1.189; 95% CI 1.053 to 1.342; p=0.005) were independently associated with poor functional outcome. However, the independent association between intraprocedural BPV and PH at 24 hours has not been established in this study.

CONCLUSIONS

Increased intraprocedural BPV was more likely to have poor functional outcome in patients with LVO following MT with general anaesthesia. This finding indicates that special precautions should be taken to minimise BP fluctuation during procedure.

Hemodynamics of Leptomeningeal Collaterals after Large Vessel Occlusion and Blood Pressure Management with Endovascular Treatment

Endovascular therapy (EVT) is an effective treatment for ischemic stroke due to large vessel occlusion (LVO). Unlike intravenous thrombolysis, EVT enables visualization of the restoration of blood flow, also known as successful reperfusion in real time. However, until successful reperfusion is achieved, the survival of the ischemic brain is mainly dependent on blood flow from the leptomeningeal collaterals (LMC). It plays a critical role in maintaining tissue perfusion after LVO via pre-existing channels between the arborizing pial small arteries or arterioles overlying the cerebral hemispheres. In the ischemic territory where the physiologic cerebral autoregulation is impaired and the pial arteries are maximally dilated within their capacity, the direction and amount of LMC perfusion rely on the systemic perfusion, which can be estimated by measuring blood pressure (BP). After the EVT procedure, treatment focuses on mitigating the risk of hemorrhagic transformation, potentially via BP reduction. Thus, BP management may be a key component of acute care for patients with LVO stroke. However, the guidelines on BP management during and after EVT are limited, mostly due to the scarcity of high-level evidence on this issue. In this review, we aim to summarize the anatomical and physiological characteristics of LMC to maintain cerebral perfusion after acute LVO, along with a landscape summary of the literature on BP management in endovascular treatment. The objective of this review is to describe the mechanistic association between systemic BP and collateral perfusion after LVO and thus provide clinical and research perspectives on this topic.