This article is more than 5 years old. Information may no longer be current.
MR CLEAN: Nongeneral anesthesia may lead to better outcomes after intra-arterial treatment
NASHVILLE, Tenn. — Among patients randomly assigned to intra-arterial treatment in the MR CLEAN trial, use of nongeneral anesthesia during the procedure was associated with better outcomes compared with use of general anesthesia, according to findings presented at the International Stroke Conference.
The phase 3, multicenter, open-label MR CLEAN study enrolled patients with acute ischemic stroke caused by an intracranial occlusion in the anterior circulation artery; 217 underwent intra-arterial treatment after randomization. Previously published results demonstrated that the treatment group had better results for all outcomes compared with controls.
There is currently no consensus on the optimal anesthetic management in intra-arterial treatment, so the researchers analyzed functional outcomes and safety of those in the MR CLEAN treatment group, divided by whether they received general anesthesia (n = 80) or nongeneral anesthesia (n = 137), Olvert A. Berkhemer, MD, from the Academic Medical Center in Amsterdam, said during a press conference.
The primary outcome was modified Rankin scale score at 90 days. Secondary outcomes included timing, safety parameters and procedure-related adverse events.
Compared with general anesthesia, patients who received nongeneral anesthesia had faster times from door to start of intra-arterial treatment (134 minutes vs. 162 minutes; adjusted beta = 31; 95% CI, 13-50) and from randomization to start of intra-arterial treatment (50 minutes vs. 64 minutes), Berkhemer said. The groups did not differ in procedural duration or onset-to-revascularization time.
Rates of death between the two groups were similar (general anesthesia at 7 days, 15%; nongeneral anesthesia at 7 days, 13%; general anesthesia at 30 days, 18%; nongeneral anesthesia at 30 days, 19%), Berkhemer said.
Fifty-four percent of patients who received general anesthesia had at least one serious adverse event vs. 42% who received nongeneral anesthesia. The difference was mainly driven by rates of progressive ischemic stroke (general anesthesia, 30%; nongeneral anesthesia, 12%), according to Berkhemer.
Compared with patients assigned control therapy in MR CLEAN, those who underwent intra-arterial treatment under nongeneral anesthesia had a better distribution on the modified Rankin scale (common adjusted OR = 2.13; 95% CI, 1.46-3.11), but the same was not observed for those who underwent intra-arterial treatment under general anesthesia (common adjusted OR = 1.09; 95% CI, 0.69-1.71; P for trend = .013).
“The effect of general anesthesia vs. control is almost not present,” Berkhemer said.
Similarly, compared with controls, patients who underwent intra-arterial treatment under nongeneral anesthesia had better odds of good functional outcome, defined as modified Rankin scale score of 0 to 2, at 90 days (adjusted OR = 2.79; 95% CI, 1.7-4.59), but that outcome was no different between controls and those who underwent intra-arterial treatment under general anesthesia (adjusted OR = 1.09; 95% CI, 0.56-2.12).
“General anesthesia is associated with delayed treatment initiation in the MR CLEAN trial,” Berkhemer said. “There was a significant interaction with treatment. The effect on the outcome that we found in the MR CLEAN trial was not observed in the subgroup of patients treated with general anesthesia.”
However, Berkhemer said it is unclear whether the delayed treatment initiation associated with general anesthesia is a factor in the difference in outcomes, but he noted that time to reperfusion did not differ based on anesthesia type.
A possible explanation is that “if you induce general anesthetics, you can have lowering of BP, and that’s something you want to avoid when you treat stroke patients,” he said. “You want to have a little bit higher BP so you can have perfusion to the brain.” – by Erik Swain
For more information:
Berkhemer OA. Plenary Session III: LB17. Presented at: International Stroke Conference; Feb. 11-13, 2015; Nashville, Tenn.
Disclosure: The study was supported by the Dutch Heart Foundation and by unrestricted grants from AngioCare, Covidien/ev3, Medac/Lamepro and Penumbra. Berkhemer reports no relevant financial disclosures.
Perspective
Back to Top
The biggest takeaway is a suggestion that people who receive general anesthesia might not get the same kind of benefit from intra-arterial treatment as those who receive local anesthesia. Apart from this particular study, we know that a systematic review has shown exactly the same thing.
There has not been a randomized study, however, and we will probably never see one. There would be too many safety implications to justify it in the United States. Most interventions in the U.S. tend to err on the side of using local anesthesia if they can, because they want to start the treatment as quickly as possible, and it is a hassle to wait for the anesthesia. But there are patients who move too much under local anesthesia, and you want to make sure the procedure is done in as safe a manner as possible. I think the field will gravitate toward doing local anesthesia, and there will be individual instances of having to do general anesthesia.