According to this study, researchers tested of removing the clot by thrombectomy in patients presenting with a 6 to 16 hour after stroke onset and still having salvageable brain tissue identified on perfusion imaging. The study is published in the New England Journal of Medicine.

Maarten Lansberg said, “Quite a few trials have looked at the comparison of thrombectomy performed under general anesthesia vs conscious sedation and some of these have shown a worse outcome with general anesthesia, so we wanted to look at this too." However, results of subgroup analysis suggest that this benefit is greatly curtailed in patients receiving the procedure under general anesthesia.

"I would recommend from these results that general anesthesia should be avoided if possible in patients having endovascular therapy for stroke," said Maarten Lansberg. "We tried to discourage general anesthesia in this trial because of prior data suggesting worse outcomes with this approach, but some sites prefer to use general anesthesia.

So we still had 28% of our patients treated that way, and the other 72% received conscious sedation," Dr Lansberg noted. When the patients treated with thrombectomy under conscious sedation were compared with the control group, there was a larger benefit and it was significant.

But when patients in the thrombectomy group who received the procedure under general anesthesia were compared with the control group, the benefit was much smaller and not significant, Dr Lansberg reported. However, he cautioned that the sample size was small, so it would be difficult to show statistical significance.

The relative risk for a good outcome with endovascular therapy under general anesthesia versus conscious sedation was 0.44 (95% confidence interval, 0.2 – 0.9). "There was a statistical difference towards worse outcomes under general anesthesia that was not explained by imbalances in the patients' baseline characteristics," Dr Lansberg added.

"However, this comparison was not randomized and we can't eliminate all biases."  "But I don't think we want to use it just to supposedly make the procedure easier. Our results suggest that that is not a good idea."

"It really comes down to operator preference," he added. "Some operators prefer general anesthesia because the patient obviously remains much more still, which is an advantage when performing such a delicate procedure on brain vasculature in terms of complications.

But we found patients receiving general anesthesia actually had the same rate of symptomatic hemorrhage and vasculature perforation as those receiving conscious sedation in this study." Commenting on the results, Bruce Ovbiagele, MD, Medical University of South Carolina, Charleston, and ISC 2018 program chair, said general anesthesia for this procedure "is a concern."

Author concludes that few centers are used to dealing with general anesthesia than others. It's not just selecting the best device and the right patient for endovascular therapy.