Extended-release Epidural Morphine for Acute Post-operative Analgesia Following Selective Dorsal Rhizotomy in Children

Extended-release Epidural Morphine for Acute Post-operative Analgesia Following Selective Dorsal Rhizotomy in Children

Randomized, Double-Blinded Placebo Controlled Trial of Epidural, Sustained-relief Morphine for Acute Post-operative Analgesia Following Selective Dorsal Rhizotomy in Children

The purpose of this proposal is to improve the investigators' current Selective Dorsal Rhizotomy (SDR) analgesia protocol by eliminating or minimizing the use of fentanyl in the post-operative period. Children undergoing SDR for spastic cerebral palsy have significant post-operative pain. The procedure requires dissection of the lumbar back musculature and removal of the L1 lamina (the bony posterior part of the vertebra). The majority of the operation is intradural, and a water-tight dural closure at the termination of the operation is critical in order to prevent leakage of cerebrospinal fluid (CSF) from the wound. In fact, these children must remain flat on their back for 48 hours to allow the dural incision to heal prior to mobilization. Thus, adequate pain control is essential not only for patient comfort, but also to prevent agitation and additional stress on the dural closure. Currently, the investigators' patients undergoing SDR are treated for 48 hours with scheduled intravenous (IV) narcotic (continuous fentanyl infusion at 0.5-2.0 μg/kg/hour) in addition to the sedative/muscle relaxant Valium (0.2 mg/kg IV every 4 hours for 24 hours, then every 6 hours for 24 hours). The IV fentanyl, and to a lesser degree Valium, carries a real risk of hypotension and respiratory depression and requires frequent dose adjustments to achieve adequate analgesia. By improving the current SDR analgesia protocol, the investigators hope to maximize patient safety and comfort while maintaining the effectiveness of the operation by minimizing the risk of CSF leak.

improve the investigators' current Selective Dorsal Rhizotomy (SDR) analgesia protocol by eliminating or minimizing the use of fentanyl in the post-operative period. Children undergoing SDR for spastic cerebral palsy have significant post-operative pain. The procedure requires dissection of the lumbar back musculature and removal of the L1 lamina (the bony posterior part of the vertebra). The majority of the operation is intradural, and a water-tight dural closure at the termination of the operation is critical in order to prevent leakage of cerebrospinal fluid (CSF) from the wound. In fact, these children must remain flat on their back for 48 hours to allow the dural incision to heal prior to mobilization. Thus, adequate pain control is essential not only for patient comfort, but also to prevent agitation and additional stress on the dural closure. Currently, the investigators' patients undergoing SDR are treated for 48 hours with scheduled intravenous (IV) narcotic (continuous fentanyl infusion at 0.5-2.0 μg/kg/hour) in addition to the sedative/muscle relaxant Valium (0.2 mg/kg IV every 4 hours for 24 hours, then every 6 hours for 24 hours). The IV fentanyl, and to a lesser degree Valium, carries a real risk of hypotension and respiratory depression and requires frequent dose adjustments to achieve adequate analgesia. By improving the current SDR analgesia protocol, the investigators hope to maximize patient safety and comfort while maintaining the effectiveness of the operation by minimizing the risk of CSF leak.

DepoDur will be administered at 80μg/kg (not to exceed 5 mg total/patient) under direct vision in the L1 laminectomy defect prior to wound closure.

DepoDur will be administered at 120μg/kg (not to exceed 10 mg total/patient) under direct vision in the L1 laminectomy defect prior to wound closure.

Preservative-free normal saline (2.5ml) will be placed in the L1 laminectomy defect and also dispensed 1-2 levels above and 1-2 levels below using a flexible angiocatheter prior to wound closure.

After completion of the rhizotomy, the dura will be closed in the standard water-tight fashion with running suture. Epidural DepoDur (80μg/kg) will be placed under direct vision in the L1 laminectomy defect. It will also be dispensed 1-2 levels above and 1-2 levels below using a flexible angiocatheter.

After completion of the rhizotomy, the dura will be closed in the standard water-tight fashion with running suture. Epidural DepoDur (120μg/kg) will be placed under direct vision in the L1 laminectomy defect. It will also be dispensed 1-2 levels above and 1-2 levels below using a flexible angiocatheter.

After completion of the rhizotomy, the dura will be closed in the standard water-tight fashion with running suture. Preservative-free normal saline (2.5 ml) will be placed under direct vision in the L1 laminectomy defect. It will also be dispensed 1-2 levels above and 1-2 levels below using a flexible angiocatheter.

Mean and standard deviation for standardized, age-appropriate pain scales (per patient per day) 48hrs post surgery. As is standard of care at St. Louis Children's Hospital, pain level was scored based on age using the "Face, Legs, Activity, Cry, Consolability" (FLACC) for participants aged 0-3, the FACES scale on participants between the age of 3 and 5, numeric pain rating scale (NRS) on participants between the age of 5 and 8 years, or the Individualized Numeric Rating Scale (INRS) for participants greater than or equal to 8 years of age. All four of the scales were ranged from 0-10 scores, with 0 being no pain at all, and 10 being extreme pain. Each patient had two scores given, one at 24hrs and one at 48hrs post surgery. The output was reported as an average of all scores for all patients within each group.

Mean and standard deviation of total quantity of fentanyl administered (per patient per day) 48hrs post surgery.

Inclusion Criteria: Receiving selective dorsal rhizotomy (SDR) Willingness to Participate Exclusion Criteria: Known Morphine Allergy Inability to speak and read the English language

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