Is Methylnaltrexone Necessary for Post Op GI Recover?

A new randomized, double-blind, controlled trial from the Ohio State University Wexner Medical Center and Cleveland Clinic Akron General has tested the proposition that methylnaltrexone is actually necessary to ensure normal bowel functioning after surgery—even with opioid use.

Their study, “Perioperative subcutaneous methylnaltrexone does not enhance gastrointestinal recovery after posterior short-segment spinal arthrodesis surgery: a randomized controlled trial,” appears in the Spine Journal.

H. Francis Farhadi, M.D., Ph.D., complex spine and peripheral nerve surgeon at Ohio State Wexner and study co-author explained the objective of the study to OTW, “As the frequency of spinal procedures for lumbar degenerative conditions has increased over time, so too have patients' expectations for accelerated complication-free recovery to full functional activity levels. This multidisciplinary study was performed as part of an Enhanced Recovery after Surgery initiative to determine whether peri-operative administration of methylnaltrexone could facilitate bowel functional recovery after spinal fusion surgery, an ongoing clinical dilemma for which no effective preventative strategies currently exist.”

Looking at gastrointestinal recovery specifically after short-segment lumbar arthrodesis surgeries, the authors enrolled 82 patients (41 received methylnaltrexone and 41 received placebo).

The researchers found no difference in median time-to-bowel initial movement between the two groups [61.8 hours versus 50.7 hours]. There was also no difference in time-to-discharge/discharge eligibility [105.0 hours versus 90.7]. They discovered no differences in either postoperative opioid consumption or numeric rating scores for back, leg, or abdominal pain on postoperative days 0 to 4 (p>.05).

“Neither the average time-to-first bowel movement nor the incidence of post-operative ileus (loss of bowel motility) were affected by peri-operative methylnaltrexone administration,” said Dr. Farhadi to OTW. “Methylnaltrexone administered peri-operatively was nevertheless safe and did not negatively impact patient pain levels or post-operative opioid medication requirements.”

“Currently employed methylnaltrexone dosing regimens for treatment of opioid-induced constipation do not appear to be effective for prophylactic treatment of bowel dysfunction commonly noted after spine surgery. Further studies should focus on novel dosing regimens particularly for spinal surgeries that involve exposure to larger opioid doses (e.g., corrective surgeries for adult spinal deformity).”