Reducing opioid usage: a pilot study comparing postoperative selective dorsal rhizotomy protocols

J Neurosurg Pediatr. 2019 Nov 22:1-6. doi: 10.3171/2019.9.PEDS19398. Online ahead of print.

Abstract

Objective: Selective dorsal rhizotomy (SDR) is a surgical procedure used to treat spasticity in children with spastic cerebral palsy. Currently, there is a lack of work examining the efficacy of optimizing pain management protocols after single-level laminectomy for SDR. This pilot study aimed to compare the clinical outcomes of SDR completed with a traditional pain management protocol versus one designed for opioid dosage reduction.

Methods: The Texas Comprehensive Spasticity Center prospective database was queried for all patients who underwent SDR between 2015 and 2018. Demographic, surgical, and postoperative data for all patients who underwent SDR were collected from medical records. The study was designed as a retrospective study between the patient-controlled analgesia (PCA) and dexmedetomidine infusion (INF) groups with 80% power to detect a 50% difference at a significance level of 0.05. Patients in the INF group received perioperative gabapentin, intraoperative dexmedetomidine infusion, and scheduled acetaminophen and NSAIDs postoperatively.

Results: Medication administration records, pain scores, and therapy notes were collected for 30 patients. Patients who underwent SDR between June 2015 and the end of December 2017 received traditional pain management (PCA group, n = 14). Patients who underwent SDR between January 2018 and the end of December 2018 received modified pain management (INF group, n = 16). No patients were lost to follow-up. Differences in age, weight, height, preoperative Gross Motor Function Classification System scores, operative duration, hospital length of stay, and sex distribution were not statistically different between the 2 groups (p > 0.05). Analysis of analgesic medication doses demonstrated that the INF group required fewer doses and lower amounts of opioids overall, and also fewer NSAIDs than the PCA group. When converted to the morphine milligram equivalent, the patients in the INF group used fewer doses and lower amounts of opioids overall than the PCA group. These differences were either statistically significant (p < 0.05) or trending toward significance (p < 0.10). Both groups participated in physical and occupational therapy similarly postoperatively (p > 0.05). Pain scores were comparable between the groups (p > 0.05) despite patients in the INF group requiring fewer opioids.

Conclusions: Infusion with dexmedetomidine during SDR surgery combined with perioperative gabapentin and scheduled acetaminophen and NSAIDs postoperatively resulted in similar pain scores to traditional pain management with opioids. In addition, this pilot study demonstrated that patients who received the INF pain management protocol required reduced opioid dosages and were able to participate in therapy similarly to the control PCA group.

Keywords: CP = cerebral palsy; GMFCS = Gross Motor Function Classification System; INF = dexmedetomidine infusion protocol; LOS = length of stay; MME = morphine milligram equivalent; PCA = patient-controlled analgesia; POD = postoperative day; PRN = pro re nata (as needed); SDR = selective dorsal rhizotomy; dexmedetomidine; opioid; pain; selective dorsal rhizotomy; spine; therapy.