The use of acupuncture for craniotomy may improve analgesia, reduce the required anesthetic dosage, and decrease postoperative nausea and vomiting (PONV), according to a Cochrane systematic review and meta-analysis published in the Journal of Neurosurgical Anesthesiology (2016 Mar 10. Acupuncture also might have protective effects on brain tissue, according to this analysis.
“Acupuncture treatment has been used in China for [more than] 2,500 years, and at present it is used worldwide as a form of analgesia in patients with acute and chronic pain,” the researchers wrote. “Furthermore, acupuncture is regularly used not only as a single anesthetic technique but also as a supplement or in addition to general anesthesia (GA).”
Included in the meta-analysis were studies that involved any craniotomy performed under GA compared with a combination of GA and acupuncture. Exclusion criteria were no acupuncture during surgery, no GA during surgery, only postoperative data available, animal studies and low grade of evidence. The study included 10 prospective, randomized controlled clinical trials (N=700). It was overseen by Sven Asmussen, MD, who was a postdoctoral fellow at the University of Texas Medical Branch at Galveston, at the time the research was conducted. He did not respond to requests to comment for this article.
Inhaled anesthetic dose was reduced significantly when acupuncture was used during craniotomy (P<0.001). Acupuncture also was associated with faster extubation (P=0.001), reduced PONV (P=0.017) and shorter postoperative recovery (P=0.003). The reviewers also found significantly reduced blood levels of the brain tissue injury marker S100β at 48 hours postoperatively (P=0.001). No patient was noted to have experienced intraoperative awareness.
It is important to note that anesthetic requirement was presented in terms of end-tidal percentage across three volatile anesthetics, each of which has a different potency. Mean alveolar concentration would be a more precise and conventional measure of anesthetic dosage.
“The currently available literature is based on high evidence-grade studies, although the number of studies and patients is relatively small,” the researchers said. “This meta-analysis shows that additional electrostimulated acupuncture with needle placement through trained acupuncturists in patients undergoing GA for craniotomy may be beneficial because of reduced anesthetic consumption, faster recovery from anesthesia and reduced onset of PONV. Randomized controlled multicenter trials are warranted to better understand underlying mechanisms and to further elucidate the protective effects of electroacupuncture on the brain tissue, as well as the economical potential of reduced anesthetic consumption,” the authors wrote.
But … Not So Fast
However, expert opinion called these findings into question. “There are serious problems with the meta-analysis by Asmussen and colleagues,” noted Daniel I. Sessler, MD. “The major sources of error in meta-analyses are 1) selection bias (in choosing studies for inclusion); 2) weaknesses in the underlying studies; and 3) publication bias. At least the second two are likely in this case,” he said. Dr. Sessler is Michael Cudahy Professor and Chair of the Department of Outcomes Research, Anesthesiology Institute at the Cleveland Clinic.
In contrast, Michael Roizen, MD, had a more positive view, saying, “This meta-analysis indicates from non–randomized controlled trials a cost savings benefit of adding electroacupuncture in neurosurgery. Other studies have supported shorter ICU stays and decreased need for pain medication [with acupuncture]. This meta-analysis shows reduced anesthesia use during surgery and now possible neuroprotective effects on the brain.” Dr. Roizen is chair of the Wellness Institute at the Cleveland Clinic.
“That’s in addition to the positive clinical outcomes: decreased postoperative nausea and vomiting, and cardioprotective effects in cardiac surgical patients—decreased troponin, lower inotrope scores. It is time for a randomized double-blind, gold-standard trial,” Dr. Roizen said.
Dr. Sessler pointed out other shortcomings with this meta-analysis, however. “The underlying studies—all published in nonstandard journals—are not strong,” he noted. “A limitation acupuncture investigators face is that studies are hard to blind. But blinding is critical, and even purportedly objective findings are biased in unblinded trials,” he explained.
He also noted that confidence intervals are a measure of result dispersion and provide no information about confounding and bias, both of which are usually larger sources of error than chance. “The authors claim that there was no evidence of publication bias, but do not provide a conventional funnel plot, and even that at best would be weak evidence,” Dr. Sessler said.
Another anesthesiologist, Alex Macario, MD, commented, “Part of the difficulty of studying acupuncture is that the acupuncture intervention is not always consistent and the same across studies. The number of acupoints, the location of the acupoints [Table], how long the electrical stimulation acupuncture is delivered, when the acupuncture is delivered pre-op versus intra-op are all variables that complicate a clear understanding of acupuncture’s benefits or mechanism of action. The sham controls can also be quite different among studies.” Dr. Macario is professor in the Departments of Anesthesiology, Perioperative and Pain Medicine, and Health Research and Policy at Stanford University School of Medicine, in California. He also is vice chair of education and program director of the anesthesia residency program at Stanford.
“It is noteworthy that acupuncture has gained the attention of the National Institutes of Health. The National Center for Complementary and Integrative Health is funding acupuncture studies in a variety of areas to better understand its value. This tells us there is some potential that is worthy of investigation,” he suggested.