Assessing the Safety of General Anesthesia in Hip Fracture Patients
Each year, 250,000 older adults in the US undergo surgery for hip fracture fixation. Although most of these patients receive general anesthesia, the use of spinal anesthesia in hip fracture surgery is becoming more common, increasing by 50% between 2007 and 2017.
With the greater utility of spinal anesthesia, should general anesthesia be abandoned for hip fracture surgery to spare older patients the possible consequences of general anesthesia, such as postoperative delirium and delayed functional recovery?
Not at all, according to a multicenter study recently published online ahead of print by the New England Journal of Medicine. In that study, general anesthesia was found to as safe as spinal anesthesia for hip fracture patients, with similar rates of survival, functional recovery, and postoperative delirium.
Challenging Conventional Thinking
The study, conducted at 46 institutions in the US and Canada, is the largest randomized trial to compare the 2 anesthesia techniques, and the findings challenge the common belief that patients who receive spinal anesthesia fare better than those who receive general anesthesia.
“Available evidence has not definitively addressed the question of whether spinal anesthesia is safer than general anesthesia for hip fracture surgery, an important question [for] clinicians, patients, and families,” said lead investigator Mark D. Neuman, MD, MSc, an Associate Professor of Anesthesiology and Critical Care from the Perelman School of Medicine at the University of Pennsylvania in Philadelphia.
“Our study argues that, in many cases, either form of anesthesia appears to be safe. This is important because it suggests that choices can be guided by patient preference rather than anticipated differences in outcomes in many cases.”
Most of the recent comparisons of general anesthesia and spinal anesthesia have come from studies in which patients were not randomized, and some of these studies have suggested that spinal anesthesia is superior, with lower rates of cognitive and medical complications. The advantage of the present study is the 1:1 randomization of anesthesia type in hip fracture patients.
Dr. Neuman and his co-authors enrolled 1,600 patients with a hip fracture who were all at least 50 years old and had been able to walk prior to the fracture. They randomized 795 patients to the spinal anesthesia group and 805 to the general anesthesia group.
For a better picture of the potential outcomes associated with each form of anesthesia, the researchers set their primary outcome as a composite of patient death rates and whether they regained the ability to walk approximately 10 feet (3 meters) independently or with an assistive device (walker or cane) by 60 days after randomization. Their secondary outcomes were death within 60 days, delirium, time to discharge, and ambulation at 60 days
The researchers found that for the primary outcome, 18.5% of patients assigned to spinal anesthesia had either died or become newly unable to walk versus 18% of patients who received general anesthesia (P=0.83). When looking at the components of the primary outcome individually, they found that:
- 15.2% of spinal anesthesia and 14.4% of general anesthesia patients were unable to walk independently
- 3.9% of spinal anesthesia patients 4.1% of general anesthesia had died in the 60 days since surgery
To evaluate how the different forms of anesthesia factored into potential cognitive complications, the researchers also examined postoperative delirium among patients in the 2 groups. They found that 20.5% of spinal anesthesia patients and 19.7% of general anesthesia patients experienced delirium.
The researchers said that based on their findings, general anesthesia is not inferior to spinal anesthesia in terms of mortality and the ability to walk postoperatively in patients who have undergone surgery for hip fracture fixation.
“What our study offers is reassurance that general anesthesia can represent a safe option for hip fracture surgery for many patients,” Dr. Neuman said. “This is information that patients, families, and clinicians can use together to make the right choice for each patient’s personalized care.”
More information about the study can be found on ClinialTrials.gov.
Neuman MD, Feng R, Carson JL, and the REGAIN Investigators. Spinal anesthesia or general anesthesia for hip surgery in older adults. N Engl J Med. 2021 Oct 9. doi: 10.1056/NEJMoa2113514. Online ahead of print.