General Anesthesia for Endovascular Thrombectomy; A Pilot Study.

Study Overview
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Brief Summary
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This study evaluates the outcomes of stroke patients treated for intravascular thrombectomy, using either a local anesthetic with sedation, or a general anesthetic. Historical data will be used for those treated with the local anesthetic, and prospective data will be used for those treated with the general anesthetic.

Detailed Description
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This is an open-label pilot study, comparing intravascular thrombectomy patients treated using either general anesthetic (prospective arm) or local anesthetic with sedation (retrospective arm), with blinded outcome evaluation. New evidence has established that the addition of endovascular thrombectomy for large, and/or proximal occlusions improves outcome in addition to, and/or in place of tPA therapy. There have been no randomized prospective trials assessing the relationship of anesthesia on outcomes for this procedure. This procedure is routinely performed under either local anesthetic with sedation and under general anesthesia (GA). The choice between these two techniques is largely institution based. Currently in the Saskatoon Health Region (SHR) endovascular thrombectomies are performed under general anesthesia due to operator preference and the optimization of surgical conditions. In the United States and other Canadian centers, this procedure is performed safely with local anesthesia with or without sedation. Several retrospective trials have suggested that general anesthetics are associated with poorer outcomes. It has been suggested that general anesthesia can result in a delay in the time to procedural start since it requires the presence of an anesthesiologist and the procedure can be performed under sedation without extra personnel. It is also proposed that the induction of general anesthesia can cause a decrease in blood pressure and a decrease in collateral perfusion which can result in further cellular hypoxia. Anesthesiologists , however, are able to expertly manipulate hemodynamic parameters during general anesthesia to the specific requirements of the operators potentially creating optimal tissue oxygenation conditions. There is a need for a prospective trial to assess the effect of general anesthetic on patient outcome during endovascular thrombectomy. At this time, it is premature to conduct a randomized controlled trial (RCT). Therefore in this pilot study, adult acute ischemic stroke participants who undergo intravascular thrombectomy in Saskatchewan will receive a general anesthetic as per their current practice, and their data will be collected prospectively. This cohort of participants will then be compared to participants that underwent the same procedure in another study, who received local anesthesia with sedation. Approximately 77 prospective participants will be recruited for the prospective arm of this study.

Official Title
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General Anesthesia for Endovascular Thrombectomy; A Pilot Study.

Conditions
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Stroke, Cerebrovascular Stroke, Brain Ischemia, Brain Diseases, Cardiovascular Diseases, Central Nervous System Diseases, Cerebrovascular Disorders, Nervous System Diseases, Vascular Diseases

Intervention / Treatment
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* Drug: Sevoflurane
* Drug: Lidocaine


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Acute ischemic stroke Age 18 or greater Onset (last seen well) time to treatment less than 12 hours Disabling stroke defined as a baseline NIHSS > 5 at the time of treatment Pre-stroke independent functional status in activities of daily living. Patient must be living in their own home, apartment or seniors lodge where no nursing care is required Pre-enrollment non-intubated state based on acceptable GCS for the prospective Cohort Small core proximal occlusion as confirmed by CT angiography (carotid, M1 MCA or M1 MCA equivalent) Intention to initiate endovascular treatment within 60 minutes of baseline non-contrast CT Sevoflurane used during thrombectomy Appropriate consent provided Exclusion Criteria: Baseline non-contrast CT reveals a moderate/large core defined as extensive early ischemic changes of ASPECTS 0-5 in the territory of symptomatic intracranial occlusion Hemorrhagic stroke Clinical history, past imaging or clinical judgment suggests that the intracranial occlusion is chronic Intubated state based on GCS at any time prior to induction of general anesthesia for prospective cohort

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Prospective - General Anesthetic<br>The prospective treatment group will have an anesthetic induction according to the anesthetic provider's preference that will include propofol and fentanyl as IV induction agents and rocuronium as a muscle paralytic. Maintenance of anesthesia for the treatment group will include sevoflurane with a target end tidal concentration of 1-1.5%, rocuronium as a paralytic as needed, opioids and any other standard medication deemed necessary by the provider. | Drug: Sevoflurane<br> <br> |
| Retrospective - Local Anesthetic with Sedation<br>The retrospective group will have received local anesthetic from the surgeon using lidocaine injected subcutaneously and received sedation using fentanyl and midazolam as needed to achieve the desired level of sedation. | Drug: Lidocaine<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Shift in the mRS score, defined by a proportional odds model. |  | 90 Days | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The proportion of patients who achieve a NIHSS score 0-2 | Stroke severity. Clinical scale outcome score from 0 to 42. | 90 Days | 
| The proportion of patients who achieve a mRS 0-2 | Functional outcome. Dichotomous outcome, reported as independent (mRS 0-2) vs dependence or death (mRS 3-6). In addition, shift analysis (proportional odds model) representing the odds of improvement within the scale with treatment. | 90 days | 
| Recanalization of the target arterial occlusive lesion | Measured by fluoroscopy - Demonstrated during (or as part of) the procedure. | Day 0 | 
| Time from diagnostic CT to procedure initiation |  | Day 0 | 
| Time from the start of the procedure to vascular recanalization |  | Day 0 | 
| Incidence of Treatment-Emergent Adverse Events | Episodes of hypo/hypertensive and bradycardic episodes that required the use of pharmacologic agent.; Symptomatic intracranial hemorrhage; Major bleeding; Contrast nephropathy; Malignant MCA infarction; Hemicraniectomy; Aspiration Pneumonia; Adverse airway event; other | 90 Days | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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stroke, endovascular, thrombectomy, ischemic stroke, general anesthetic, local anesthetic, recanalization