Authors of the Swedish study recommend considering general anesthesia as a viable option and seeking input for neuroanesthesiologists.
General anesthesia is just as safe an option as conscious sedation during endovascular treatment of ischemic stroke, according to the AnStroke randomized trial.
In an email to Neurovascular Exchange, lead authors Pia Löwhagen Hendén, MD, and Alexandros Rentzos, MD (Sahlgrenska University Hospital, Gothenburg, Sweden), explained that conscious sedation became the preferred choice for stroke interventions particularly after 2010, when several retrospective reports linked general anesthesia to poorer neurological outcomes.
“The majority of neurointerventional centers, including our own, where general anesthesia was the standard method, changed or considered changing to conscious sedation due to these retrospective studies,” they said. “However, preferences were not the same all over the country in Sweden or, as far as we know, in the rest of the world either.” Several surveys have revealed either a preference for general anesthesia or disagreement on whether to intubate ischemic stroke patients undergoing endovascular interventions, they pointed out.
Yet they were reluctant to believe the negative impact on neurological outcomes, Hendén and Rentzos said. “Most retrospective studies on anesthesia technique did not describe the anesthesia technique, nor the anesthetic management! Furthermore, the selection bias for general anesthesia was striking. In our institute, the most common anesthesia form, since the early 1990s when we started endovascular stroke treatment, was general anesthesia, and in our experience general anesthesia is not associated with poor outcome.”
The investigators decided to settle the question with the AnStroke trial. As outlined in their paper published in the June 2017 issue of Stroke, they randomized 90 patients receiving endovascular treatment for acute ischemic stroke between 2013 and 2016 to either general anesthesia or conscious sedation during the procedure.
A similar proportion of patients in each group attained a good neurological outcome at 3 months postprocedure. In addition, there were no differences between the two groups with respect to numerous outcomes including rates of successful recanalization, 24-hour National Institutes of Health Stroke Scale (NIHSS) score, and in-hospital hospital mortality.
Outcomes by Anesthesia Type
|
|
General Anesthesia (n = 45) |
Conscious Sedation (n = 45) |
P Value |
|
90-Day mRS ≤ 2 |
42.2% |
40.0% |
1.00 |
|
Intraoperative Mean Arterial Pressure as Fraction of Baseline Mean Arterial Pressure, mm Hg |
0.88 ± 0.10 |
0.89 ± 0.9 |
0.57 |
|
Intraoperative Blood Glucose, mmol/L |
7.0 (6.2-8.5) |
6.9 (6.2-8.1) |
0.80 |
|
Intraoperative PaCO2, kPa |
5.4 (4.8–5.9) |
5.2 (4.6–6.0) |
0.57 |
|
mTICI 2b-3 |
91.1% |
88.9% |
1.00 |
|
24-Hour NIHSS Score |
8 (3-5) |
9 (2-15) |
0.60 |
|
Mean Infarct Volume, mL |
20 (10-100) |
20 (10–54) |
0.53 |
|
In-Hospital Mortality |
13.3% |
13.3% |
1.00 |
Anesthesia type also had no effect on the time intervals from stroke onset to CT, groin puncture, or recanalization/end of procedure; from CT to groin puncture or recanalization/end of procedure; from arrival at the neurointerventional suite to groin puncture; or from groin puncture to recanalization/end of procedure.
Don’t Dismiss Use of General Anesthesia
Based on these findings, the authors advised against avoiding “general anesthesia during endovascular stroke treatment, which is the current practice nowadays. Especially when a difficult case is to be expected, either because of difficult anatomy, tandem occlusions, or a very agitated patient, general anesthesia should be considered.”
Deepak Sharma, MD (University of Washington (Seattle, WA), who commented on the study for NVX via email, agreed that the retrospective data had deterred the use of general anesthesia.
“With the findings of the AnStroke trial (especially in light of similar results of the SIESTA trial), providers may now rest assured about being able to safely use [general anesthesia in cases] where it may be preferable for select patients, as long as the physiological parameters can be maintained,” Sharma said.
He added that, “more than the anesthetic technique itself, the findings emphasize the importance of strict maintenance of hemodynamic goals during acute stroke interventions.”
Hendén and Rentzos pointed out to NVX that some patients may be better candidates for one anesthesia type over another. “That is why neuroanesthesiologists should be represented in the stroke team and, of course, in the decision process,” they recommended.
While acknowledging that theirs is a small, single-center trial and therefore reflects only the experience of one location, they still asserted that other centers should not be so quick to discount the option for general anesthesia. They noted that, given that their general anesthesia group happened, by chance, to have higher NIHSS score, more left-sided occlusions, and more carotid T occlusions, it is possible that general anesthesia actually offers a neuroprotective effect.
Other research has shown that inhalation anesthesia, as done in AnStroke, is tied to better neurological outcomes compared with propofol-based general anesthesia, the investigators observed. “This might be worth investigating further, as the anesthetic agents differ in their profile.”
Source:
Hendén PL, Rentzos A, et al. General anesthesia versus conscious sedation for endovascular treatment of acute ischemic stroke: The AnStroke Trial (Anesthesia During Stroke). Stroke. 2017;48:1601-1607.
Disclosures:
Rentzos, Hendén, and Sharma report no relevant conflicts of interest.
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