Pain during the first 24 hours after hip fracture repair surgery was higher following spinal anesthesia than general anesthesia, according to a study of 1600 patients published in Annals of Internal Medicine. More than 250,000 patients a year suffer a hip fracture, and the majority undergo surgery, either to repair the fracture or to replace the hip joint.
In a preplanned secondary analysis of the previously reported REGAIN (Regional Versus General Anesthesia for Promoting Independence After Hip Fracture) trial, researchers assessed pain, analgesic use, and satisfaction after hip fracture surgery with spinal vs general anesthesia. The previously published analysis found similar ambulation and patient survival rates at 60 days between between the two anesthesia methods.
Mark D. Neuman, MD, an associate professor of anesthesiology and critical care and director of the Penn Center for Perioperative Outcomes Research and Transformation (CPORT) at the University of Pennsylvania Perelman School of Medicine in Philadelphia, Pennsylvania, was the study’s lead author. In an interview with Medscape Medical News, he said, “Even though spinal anesthesia and general anesthesia have each been used for decades, patients and clinicians have lacked credible information on key measures of patient experience, such as pain and satisfaction after surgery. Our study aimed to fill that gap.”
In the initial study, researchers identified 1600 patients aged 50 years or older who were scheduled to undergo surgical repair of a clinically or radiographically diagnosed femoral neck, intertrochanteric, or subtrochanteric hip fracture at 46 hospitals in the United States and Canada. Major exclusion criteria of the study included an inability to walk approximately 10 feet or across a room without human assistance before fracture, need for a concurrent procedure not amenable to spinal anesthesia, periprosthetic fracture, and contraindications to spinal anesthesia.
The results of the study indicate that scores for patients’ worst pain over the first 24 hours after surgery were greater with spinal anesthesia (mean, 7.9 [SD, 2.6]) compared to general anesthesia (mean, 7.6 [SD, 2.8]). The mean difference was 0.40 (95% CI, 0.12 – 0.68; P < .05).
Pain scores did not differ across groups at later time points during or after hospitalization. However, postoperative opioid use was higher following spinal anesthesia at 60 days but not at 180 or 365 days.
While he can’t say for sure what led to the differences between the two anesthesia groups, Neuman does have one theory. He pointed out, “Compared to patients assigned to general anesthesia, patients assigned to spinal anesthesia received less opioid pain medication in the operating room. It’s possible that this could have contributed to the 24-hour pain differences we saw, but, again, we can’t be sure, based on the data we have.”
In a editorial commentary, Alexander Arriaga, MD, MPH, ScD, and Angela M. Bader, MD, MPH, both of Brigham and Women’s Hospital in Boston, Massachusetts, commended Neumann and his colleagues on bringing to light a study that challenged the dominant narrative that spinal anesthesia may better for hip fracture patients.
In an interview with Medscape, Arriaga, who is also patient safety editorial board member of the American Society of Anesthesiologists, said, “The authors themselves hypothesized that spinal anesthesia would be associated with less pain after hip fracture surgery, less analgesic use, and greater satisfaction with care compared with general anesthesia. Dr Neuman and colleagues are applauded for reporting on their findings even though this is not what they observed.”
However, Arriaga and Bader did note that, while statistically significant, the absolute difference in pain scores was not large, and thus asked in their commentary, “Would a difference between a pain score of 7 and 8 or a score of 8 and 9 start to become more clinically meaningful than the difference between a score of 1 and 2 on a scale from 0 to 10?”
Neuman agrees with that suggestion. He told Medscape, “The differences are small in absolute terms. However, we don’t really know what level of change constitutes a clinically significant difference for the average patient in our study or if this threshold varies across patients.”
Both Neuman and Arriaga also expressed concern that more than 70% of patients in both groups reported severe pain in the first days after surgery.
Neuman would like to see additional research to define the underlying mechanisms of differences between the groups. “There are still very few trials that rigorously examine the connection between anesthesia type and these important outcomes. My hope is that future work can build on REGAIN to verify and extend our findings.”
The study was funded by a Patient-Centered Outcomes Research Institute award. Arriaga has disclosed no relevant financial relationships.
Ann Intern Med. Published online June 14, 2022. Abstract