Largest Randomized Study
The largest multicenter randomized controlled trial comparing techniques for hip fracture anesthesia, which involved patients undergoing hip fracture repair at UF Health, found that older adults have comparable rates of survival, functional recovery and postoperative delirium with general anesthesia as with spinal anesthesia. The findings add to the nuanced discussion about which technique, spinal or general anesthesia, is best for this patient population.
The study, led by researchers at the Perelman School of Medicine at the University of Pennsylvania, is the largest randomized study ever performed to compare the techniques and was published in October in the New England Journal of Medicine. It involved 1,600 patients from 46 centers in the United States and Canada.
Joshua Sappenfield, M.D., associate professor of anesthesiology, was the site principal investigator for UF Health, where 36 patients completed the trial, and is a coauthor on the new article.
“Over the years there has been a lot of expert opinions and a shortage of data on this question,” Sappenfield said. “This study provides evidence to show that depending on patient characteristics and preference, either approach is appropriate.”
A clear takeaway from this study was the large institutional bias for or against spinal anesthesia in this setting. Of the 22,000 patients potentially randomized, only 1,600 were actually enrolled. Some institutions and patients opt for spinal anesthesia out of a belief that it may prevent complications and others opt for general anesthesia out of concern for inadequate sedation. Some observational studies have suggested that spinal anesthesia is associated with fewer complications. But existing randomized trials had reported conflicting results and most were dated, small or did not report outcomes after the patient’s hospital stay.
Details & Results
In the new study, patients were randomly divided into two equal groups, one for general and one for spinal anesthesia. At 60 days after surgery, 18.5% of patients who received spinal anesthesia had died or were unable to return to walking independently compared to 18% in the general anesthesia group. Approximately 21% of patients in the spinal anesthesia group experienced delirium compared to 20% with general anesthesia. In hospital complications and admission to the ICU was higher in the general anesthesia group but overall this did not lead to an increase in mortality.
Sappenfield said the results were surprising, having anticipated that spinal anesthesia would result in better cognitive outcomes, and reduced overall mortality. “The important clinical implication of this study is that neither anesthesia technique harms the patient,” he said. “Both spinal and general anesthesia are reasonable, equally effective anesthetic techniques for patients undergoing this surgery.”
Hip fracture surgery is common among the aging population, with about 250,000 older adults undergoing the surgery every year in the United States. The new study included patients who were at least 50 years old and had previously been able to walk.
For Sappenfield, who is also chief of the Perioperative Medicine Division and medical director of the Presurgical Clinic, participating in such a major clinical trial provided new insight and appreciation for the research process.
“It was eye-opening to observe all of the moving pieces involved in coordinating a randomized trial of this magnitude,” he said.
Now that a large pool of data has been gathered, investigators are also planning several future lines of inquiry, including studying analgesia methods. The study, led by Mark D. Neuman, M.D., MS.c., an associate professor of anesthesiology and critical care at the University of Pennsylvania, was funded by an award from the Patient-Centered Outcomes Research Institute.