Mechanical thrombectomy anesthesia

The anesthesia and critical care provider may become involved for airway management due to worsening neurologic status or to enable computerized tomography (CT) or magnetic resonance imaging (MRI) scanning, to facilitate mechanical thrombectomy, or to manage critical care of stroke patients. Existing data are unclear whether the mechanical thrombectomy procedure is best performed under general anesthesia or sedation.

Endovascular therapy (EVT) of large-vessel occlusion in acute ischemic stroke (AIS) may be performed in general anesthesia (GA) or conscious sedation (CS). Fröhlich et al. intended to determine the contribution of ischemic cerebral lesion sites on the physician's decision between GA and CS using voxel-based lesion-symptom mapping (VLSM).

In a prospective local database, we sought patients with documented AIS and EVT. Age, stroke severity, lesion volume, vigilance, and aphasia scores were compared between EVT patients with GA and CS. The ischemic lesions were analyzed on CT or MRI scans and transformed into stereotaxic space. We determined the lesion overlap and assessed whether GA or CS is associated with specific cerebral lesion sites using the voxel-wise Liebermeister test.

One hundred seventy-nine patients with AIS and EVT were included in the analysis. The VLSM analysis yielded associations between GA and ischemic lesions in the left hemispheric middle cerebral artery territory and posterior circulation areas. Stroke severity and lesion volume were significantly higher in the GA group. The prevalence of aphasia and aphasia severity was significantly higher and parameters of vigilance lower in the GA group.

The VLSM analysis showed associations between GA and ischemic lesions in the left hemispheric middle cerebral artery territory and posterior circulation areas including the thalamus that are known to cause neurologic deficits, such as aphasia or compromised vigilance, in AIS-patients with EVT. Our data suggest that higher disability, clinical impairment due to neurological deficits like aphasia, or reduced alertness of affected patients may influence the physician's decision on using GA in EVT ¹⁾.

Non-GA during MT for anterior acute ischaemic stroke with current-generation stent retriever/aspiration devices is associated with better 3-month functional outcome and lower mortality rates. These unadjusted estimates are subject to biases and should be interpreted with caution. ²⁾.

The Anesthesia During Stroke (AnStroke) trial randomised patients to GA (propofol/remifentanil for induction with sevoflurane/remifentanil maintenance) or CS (remifentanil infusion) with strict haemodynamic control, normal ventilation and normoglycaemia. There were no differences in early neurological recovery, infarct volume, or anaesthetic or neurointerventional complications ³⁾.

Retrospective cohort trials favor sedation over general anesthesia, but recent randomized controlled trials (RCT) neither suggest superiority nor inferiority of sedation over general anesthesia. Regardless of anesthesia type, a critical element of intraprocedural stroke care is tight blood pressure management ⁴⁾.

In a Systematic Review and Meta-Analysis, the use of either GA or CS during EMT for patients with anterior circulation acute ELVO does not yield significantly different rates of functional independence at 3 months ⁵⁾.

There were no significant differences in death, symptomatic intracranial hemorrhage, anesthesiologic complication, intensive care unit length of stay, pneumonia, and interventional complication. Conclusions Moderate-quality evidence suggests that general anesthesia results in significantly higher rates of functional independence than conscious sedation in patients with ischemic stroke undergoing endovascular therapy. Large randomized clinical trials are required to confirm the benefit.

In a randomized controlled trial general anesthesia does not result in worse tissue outcomes or worse clinical outcomes when compared with conscious sedation in acute stroke patients with large vessel occlusion undergoing mechanical thrombectomy ⁶⁾.