Investigators at Brigham and Women’s Hospital have found that a commonly used nerve block in arm surgeries does not lead people to be more sensitive to pain once it wears off. The findings suggest that after surgery, the sudden increase in pain after a nerve block wears off, “rebound pain,” is likely the return of normal, untreated, post-surgical pain, rather than a reaction caused by the nerve block itself.
The researchers at Brigham and Women’s Hospital in Boston, MA, were recognized for their work with a Best of Meeting Abstract Award in conjunction with the American Society of Regional Anesthesia and Pain Medicine 51st Annual Regional Anesthesiology and Acute Pain Medicine Meeting, being held April 16-18 in Phoenix, AZ.
In the absence of surgery, healthy volunteers received an axillary brachial plexus nerve block in one arm (block arm), while the other arm was left untreated. Researchers tested both arms for increased pain sensitivity using a wide range of validated pain testing modalities and found no evidence that the block arm became more sensitive. In fact, the block arm may have even shown reduced sensitivity during nerve block resolution and up to 3 hours after healthy volunteers regained full movement in their previously blocked arm.
“Rebound pain may reflect the simple return of surgical pain, in the absence of adequate regional duration, education, realistic expectations, and multimodal analgesic regimens,” the authors concluded.
