While a few articles from medical organizations and expert societies briefly discuss the use of methocarbamol in pediatric surgical patients, there remains a notable lack of robust evidence supporting their use. One study examining spinal fusion surgeries for pediatric patients with idiopathic scoliosis proposed intravenous (IV) methocarbamol at 15 mg/kg (up to 1000 mg) Q8H, transitioning to an oral formulation of 500-1000 mg Q8H. However, the author acknowledged the absence of systematic research evaluating its efficacy for pain relief. Similarly, other articles provided comparative dosing suggestions for utilizing muscle relaxants to manage intraoperative pain in children, despite little supporting data. Overall, it appears guidance statements are primarily based on expert opinion, highlighting the need for more rigorous investigations in pediatric surgical populations. [1], [2], [3]
A 2021 systematic review summarized outcomes associated with post-operative analgesia after posterior spinal fusion for adolescent idiopathic scoliosis. Three studies included methocarbamol use combined with gabapentin, opioid, ketorolac, ibuprofen, or acetaminophen for post-operative pain management. One study treating patients with both methocarbamol and gabapentin resulted in a trend towards improvement in infection, postoperative gastrointestinal retention, and length of stay, though these findings were not statistically significant (see Table 1 for details). Another study combining methocarbamol with multiple analgesic agents showed outcomes with significant decreases in opioid use, pediatric intensive care unit utilization, and allogeneic blood transfusions. A third study again combining methocarbamol with various analgesics, resulted in decreased total morphine consumption, length of stay, median time to first bowel movement, and number of post-discharge pain-related phone calls. This review, however, did not find or include any studies that evaluated methocarbamol monotherapy in pediatric pain management after surgery. While two studies indicated the potential benefit of methocarbamol as an adjuvant treatment for postoperative analgesia in pediatric patients, further research with isolated methocarbamol is warranted to understand the benefit of monotherapy. [4]
A 2011 retrospective study compared postoperative pain management outcomes of adolescents who did or did not self-select self-hypnosis training before Nuss procedure. Post-operative in-hospital analgesic medications included a variety of agents, including epidurals with local anesthetic, intravenous opioids by patient-controlled analgesia, and IV ketorolac; patients transitioned to oral opioids and ibuprofen. Methocarbamol 500 mg every 6 hours as needed was used to control pain and/or complaints of chest tightness when other analgesic treatments were not effective. Of 22 patients included in this study, 54% were treated with methocarbamol. The majority of patients who did not receive self-hypnosis training required methocarbamol compared to those who did receive self-hypnosis training (71% vs. 25%, p= 0.04). Initiation of methocarbamol ranged from postoperative day 2 to day 4 with hypnosis patients requiring earlier introduction of therapy compared to non-hypnosis patients. Opioid-related adverse effects were reported and included nausea, vomiting, constipation, and hypoventilation. Although this study did not evaluate outcomes specific to methocarbamol therapy, it does summarize the use of therapy for analgesia and chest tightness relief in postoperative pediatric patients. [5]
A 2003 retrospective review study compares outcomes of open repair versus minimally invasive repair of pectus excavatum (MIRPE) in 68 pediatric patients. A key finding is that MIRPE resulted in significantly shorter hospital stay (2.4 vs 4.4 days; p<0.001) and lower overall hospitalization costs compared to open repair, despite higher operating room costs. A significant factor contributing to the shorter stay with MIRPE was the postoperative pain management regimen used. The study used a multi-modal regimen of intravenous and oral analgesics without epidural catheters. This regimen included methocarbamol, a centrally-acting muscle relaxant. Methocarbamol was given intravenously for the first 48 hours after surgery at a dose of 10 mg/kg every 6 hours, then orally as needed. The article notes internists have effectively used methocarbamol for many years to treat low back pain in adults. It is considered good for treating muscle spasms with a low risk of abuse or other complications. By using this methocarbamol-containing regimen without epidurals, satisfactory pain control was achieved more rapidly, allowing faster transition to oral medications and shorter hospital stay after MIRPE. This was a significant factor in reducing the overall costs of MIRPE compared to open repair in this pediatric population undergoing pectus excavatum repair. However, the focus was on MIRPE itself, so the results for the methocarbamol analgesic regimen remain exploratory; it is likely the surgical technique had a greater impact on the results. [6]