Effect of General Anesthesia vs. Conscious Sedation on the Outcomes of Acute Ischemic Stroke Patients After Endovascular Therapy: A Meta-Analysis of Randomized Clinical Trials

The effect of general anesthesia and conscious sedation in endovascular thrombectomy for acute ischemic stroke: an updated meta-analysis of randomized controlled trials and trial sequential analysis

Objectives

General anesthesia (GA) and conscious sedation (CS) are common methods for endovascular thrombectomy (EVT) in acute ischemic stroke (AIS). However, the risks and benefits of each strategy are unclear. This study aimed to summarize the latest RCTs and compare the postoperative effects of the two methods on EVT patients.

Materials and methods

We systematically searched the database for GA and CS in AIS patients during EVT. The retrieval time was from the creation of the database until March 2023. The quality of the studies was evaluated using the Cochrane risk of bias tool. Random-effects or fixed-effects meta-analyses were used to assess all outcomes.

Results

We preliminarily identified 304 studies, of which 8 were included. Based on the pooled estimates, there were no significant differences between the GA group and the CS group in terms of good functional outcomes (mRS0-2) and mortality rate at 3 months (RR = 1.09, 95% CI: 0.95-1.24, p = 0.23) (RR = 0.95, 95% CI: 0.75-1.22, p = 0.70) as well as in NHISS at 24 h after treatment (SMD = -0.01, 95% CI: -0.13 to 0.11, p = 0.89). However, the GA group had better outcomes in terms of achieving successful recanalization of the blood vessel (RR = 1.13, 95% CI: 1.07-1.19, p < 0.0001). The RR value for the risk of hypotension was 1.87 (95% CI: 1.42-2.47, p < 0.00001); for pneumonia, RR was 1.43 (95% CI: 1.07-1.90, p = 0.01); and for symptomatic intracerebral hemorrhage, RR was 0.94 (95% CI: 0.74-1.26, p = 0.68). The pooled RR value for complications after intervention was 1.03 (95% CI, 0.87-1.22, p = 0.76).

Conclusion

In patients undergoing EVT for AIS, GA, and CS are associated with similar rates of functional independence. Further trials of a larger scale are needed to confirm these findings.

General anesthesia versus nongeneral anesthesia during endovascular therapy for acute ischemic stroke: A systematic review and meta-analysis

OBJECTIVE

This study compares the safety and efficacy of general anesthesia (GA) and nongeneral anesthesia (non-GA) on functional outcomes in patients receiving endovascular therapy for ischemic stroke.

METHODS

All available studies on the anesthetic management of patients with acute ischemic stroke in PubMed, the Cochrane Central Register of Controlled Trials, and Embase were included. We also compared the clinical outcomes in the studies with subgroup analyses of the occlusion site (anterior vs. posterior circulation) and preretriever group versus retriever group. Functional independence, mortality, successful recanalization, hemodynamic instability, intracerebral hemorrhage, and respiratory complications were considered primary or secondary outcomes.

RESULTS

A total of 24,606 patients in 60 studies were included. GA had a lower risk of 90-day functional independence (OR = 0.67, 95% CI 0.58 to 0.77), higher risk of 90-day mortality (OR = 1.29; 95% CI 1.15 to 1.45), and successful reperfusion (OR = 1.18; 95% CI 1.94 to 6.82). However, there were no differences in functional independence and mortality between GA and non-GA at 90 days after the procedure.

CONCLUSION

The study shows poorer results in the GA group, which may be due to the inclusion of nonrandomized studies. However, analysis of the RCTs suggested that the outcomes do not differ between the two groups (GA vs. non-GA). Thus, general anesthesia is as safe as nongeneral anesthesia under standardized management.

Anesthetic management of endovascular neurosurgical procedures in acute ischemic stroke patients: A systematic review of meta-analyses

Restoration of cerebral circulation in the ischemic area is the most critical treatment task for reducing irreversible neuronal injury in ischemic stroke patients. The recanalización of appropriately selected patients became indispensable for improving clinical outcomes and resulted in the widespread revascularization techniques. There is no clear answer as to which anesthetic modality to use in ischemic stroke patients undergoing neuro-endovascular procedures. The purpose of this systematic review is to conduct a qualitative analysis of systematic reviews and meta-analyses (RSs & MAs) comparing general anesthesia and non-general anesthesia methods for cerebral endovascular interventions in acute ischemic stroke patients. We developed a protocol with the inclusion and exclusion criteria for matched publications and conducted a literature search in PubMed and Google Scholar. The literature search yielded 52 potential publications. Ten relevant RSs & MAs were included and analysed in this review. The decision about which anesthesia method to use for endovascular procedures in managing acute ischemic stroke patients should be made based on the patient's personal characteristics, pathophysiological phenotypes, clinical characteristics, and institutional experience.

National Cost Estimates of Invasive Mechanical Ventilation and Tracheostomy in Acute Stroke, 2008-2017

BACKGROUND

Patients with stroke receiving invasive mechanical ventilation (IMV) and tracheostomy incur intense treatment and long hospitalizations. We aimed to evaluate US hospitalization costs for patients with stroke requiring IMV, tracheostomy, or no ventilation.

METHODS

We performed a retrospective observational study of US hospitalizations for acute ischemic stroke, intracerebral hemorrhage, and subarachnoid hemorrhage receiving IMV, tracheostomy, or none using the National Inpatient Sample, 2008 to 2017. We calculated hospitalization costs using cost-to-charge ratios adjusted to 2017 US dollars for inpatients with stroke by ventilation status (no IMV, IMV alone, tracheostomy).

RESULTS

Of an estimated 5.2 million (95% CI, 5.1-5.3) acute stroke hospitalizations, 2008 to 2017; 9.4% received IMV alone and 1.4% received tracheostomy. Length of stay for patients without IMV was shorter (median, 4 days; interquartile range [IQR], 2-6) compared with IMV alone (median, 6 days; [IQR, 2-13]), and tracheostomy (median, 25 days; [IQR, 18-36]; P<0.001). Mortality for patients without IMV was 3.2% compared with 51.2% for IMV alone and 9.8% for tracheostomy (P<0.001). Median hospitalization costs for patients without IMV was $9503 (IQR, $6544-$14 963), compared with $23 774 (IQR, $10 900-$47 735) for IMV alone and $95 380 (IQR, $63 921-$144 019) for tracheostomy. Tracheostomy placement in ≤7 days had lower costs compared with placement in >7 days (median, $71 470 [IQR, $47 863-$108 250] versus $102 979 [IQR, $69 563-$152 543]; P<0.001). Each day awaiting tracheostomy was associated with a 2.9% cost increase (95% CI, 2.6%-3.1%). US hospitalization costs for patients with acute stroke were $8.7 billion/y (95% CI, $8.5-$8.9 billion). For IMV alone, costs were $1.8 billion/y (95% CI, $1.7-$1.9 billion) and for tracheostomy $824 million/y (95% CI, $789.7-$858.3 million).

CONCLUSIONS

Patients with acute stroke who undergo tracheostomy account for 1.4% of stroke admissions and 9.5% of US stroke hospitalization costs. Future research should focus on the added value to society and patients of IMV and tracheostomy, in particular after 7 days for the latter procedure given the increased costs incurred and poor outcomes in stroke.

General anesthesia or conscious sedation for thrombectomy in stroke patients: an updated systematic review and meta-analysis

PURPOSE

Endovascular treatment for stroke patients usually requires anesthesia care, with no current consensus on the best anesthetic management strategy. Several randomized controlled trials and meta-analyses have attempted to address this. In 2022, additional evidence from three new trials was published: the GASS trial, the CANVAS II trial, and preliminary results from the AMETIS trial, prompting the execution of this updated systematic review and meta-analysis. The primary objective of this study was to evaluate the effects of general anesthesia and conscious sedation on functional outcomes measured with the modified Rankin scale (mRS) at three months.

METHODS

We performed a systematic review and meta-analysis of randomized controlled trials investigating conscious sedation and general anesthesia in endovascular treatment. The following databases were examined: PubMed, Scopus, Embase, and the Cochrane Database of Randomized Controlled Trials and Systematic Reviews. The Risk of Bias 2 tool was used to assess bias. In addition, trial sequence analysis was performed on the primary outcome to estimate if the cumulative effect is significant enough to be unaffected by further studies.

RESULTS

Nine randomized controlled trials were identified, including 1,342 patients undergoing endovascular treatment for stroke. No significant differences were detected between general anesthesia and conscious sedation with regards to mRS, functional independence (mRS, 0-2), procedure duration, onset to reperfusion, mortality, hospital length of stay, and intensive care unit length of stay. Patients treated under general anesthesia may have more frequent successful reperfusion, though the time from groin to reperfusion was slightly longer. Trial sequential analysis showed that additional trials are unlikely to show marked differences in mean mRS at three months.

CONCLUSIONS

In this updated systematic review and meta-analysis, the choice of anesthetic strategy for endovascular treatment of stroke patients did not significantly impact functional outcome as measured with the mRS at three months. Patients managed with general anesthesia may have more frequent successful reperfusion.

TRIAL REGISTRATION

PROSPERO (CRD42022319368); registered 19 April 2022.

General Anesthesia Versus Nongeneral Anesthesia for Patients With Acute Posterior Circulation Stroke Undergoing Endovascular Therapy: A Systematic Review and Meta-analysis

There is continued controversy regarding the optimal anesthetic technique for endovascular therapy in patients with acute posterior circulation ischemic stroke. To compare the clinical outcomes general anesthesia (GA) and non-GA, we performed a systematic review and meta-analysis of randomized controlled trials and observational studies focused on the anesthetic management for endovascular therapy in patients with acute posterior circulation stroke, without language restriction. In addition, we compared clinical outcomes among the studies with different non-GA types (conscious sedation or local anesthesia). Outcome variables were functional independence, excellent outcomes, favorable outcomes, mortality, successful recanalization, hemodynamic instability, intracerebral hemorrhage, and respiratory or vascular complications. Eight studies including 1777 patients were identified. Although GA was associated with a lower odds of functional independence at 90 days (odds ratio [OR]: 0.55; 95% confidence interval [CI] 0.38 to 0.81; P =0.009), substantial heterogeneity was noted ( I2 =65%). Subgroup analysis showed that GA was associated with higher odds of mortality than conscious sedation (OR: 1.83; 95% CI, 1.30 to 2.57; I2 =0%), but there was no difference between GA and local anesthesia ( I2 =0%). Interestingly, subgroup analysis did not identify a relationship between functional independence and GA compared with local anesthesia (OR: 0.90; 95% CI, 0.64 to 1.25; P =0.919; I2 =0%). This meta-analysis demonstrates that GA is associated with worse outcomes in patients with acute posterior circulation stroke undergoing endovascular therapy based on current studies.

Estimation of treatment effects in observational stroke care data: comparison of statistical approaches

Introduction

Various statistical approaches can be used to deal with unmeasured confounding when estimating treatment effects in observational studies, each with its own pros and cons. This study aimed to compare treatment effects as estimated by different statistical approaches for two interventions in observational stroke care data.

Patients and methods

We used prospectively collected data from the MR CLEAN registry including all patients (n = 3279) with ischemic stroke who underwent endovascular treatment (EVT) from 2014 to 2017 in 17 Dutch hospitals. Treatment effects of two interventions – i.e., receiving an intravenous thrombolytic (IVT) and undergoing general anesthesia (GA) before EVT – on good functional outcome (modified Rankin Scale ≤2) were estimated. We used three statistical regression-based approaches that vary in assumptions regarding the source of unmeasured confounding: individual-level (two subtypes), ecological, and instrumental variable analyses. In the latter, the preference for using the interventions in each hospital was used as an instrument.

Results

Use of IVT (range 66–87%) and GA (range 0–93%) varied substantially between hospitals. For IVT, the individual-level (OR ~ 1.33) resulted in significant positive effect estimates whereas in instrumental variable analysis no significant treatment effect was found (OR 1.11; 95% CI 0.58–1.56). The ecological analysis indicated no statistically significant different likelihood (β = − 0.002%; P = 0.99) of good functional outcome at hospitals using IVT 1% more frequently. For GA, we found non-significant opposite directions of points estimates the treatment effect in the individual-level (ORs ~ 0.60) versus the instrumental variable approach (OR = 1.04). The ecological analysis also resulted in a non-significant negative association (0.03% lower probability).

Discussion and conclusion

Both magnitude and direction of the estimated treatment effects for both interventions depend strongly on the statistical approach and thus on the source of (unmeasured) confounding. These issues should be understood concerning the specific characteristics of data, before applying an approach and interpreting the results. Instrumental variable analysis might be considered when unobserved confounding and practice variation is expected in observational multicenter studies.

Transcirculation Embolization to New Territory During Mechanical Thrombectomy for Acute Ischemic Stroke

Embolization in new territories (ENT) is a known complication of mechanical thrombectomy with incidence dependent upon a variety of procedural factors. We present 2 cases of anterior circulation to posterior circulation ENT. These cases were managed with manual aspiration thrombectomy with excellent radiographic and clinical outcome. We present the available literature involving ENT along with our experience in management.