The safety and efficacy of intrathecal morphine in pediatric spinal deformity surgery: a 25-year single-center experience

Effectiveness and Safety of Intrathecal Morphine for Pediatric Patients Undergoing Scoliosis Surgery: A Systematic Review and Meta-Analysis

Adolescent idiopathic scoliosis (AIS) often necessitates spinal fusion surgery in pediatric patients, posing significant challenges in postoperative pain management. Standard care involves the administration of intravenous opioids perioperatively, often requiring high doses to achieve adequate analgesia following an operation. This increases the risk of adverse events, may delay recovery and prolong hospital stay, and increases the likelihood of future abuse and dependence. In this systematic review and meta-analysis, we assess the safety and effectiveness of intrathecal morphine (ITM) in pediatric patients undergoing posterior spinal fusion. Ovid Embase and MEDLINE were searched in October 2023 for articles that directly compared ITM use with standard pain management approaches for pediatric patients undergoing posterior spinal fusion. Our primary outcome was postoperative pain scores. Secondary outcomes included opioid usage details, adverse events, and blood loss. Of the 384 unique studies identified, nine studies (one randomized control trial, one prospective review, and seven retrospective reviews) met the inclusion criteria. The total number of patients within the ITM and control groups were 1384 and 676, respectively. Meta-analysis revealed significantly lower pain scores in the ITM group (standardized mean difference (SMD): -1.30 (-2.29, -0.31); p = 0.01). Similarly, ITM patients had significantly lower opioid usage, both intraoperatively (mean difference (MD): -0.71 mg/kg (-0.99, -0.44); p < 0.00001) as well as postoperatively (SMD: -2.10 (-3.48, -0.73); p = 0.003), and significantly lower blood loss (MD: -0.88 L (-1.34, -0.43); p = 0.0001). The occurrence of adverse events was similar across both groups. Our analysis of the available data demonstrates that a low to moderate dose of ITM is a safe and effective adjunct to improve standard postoperative care without increasing the risk of respiratory depression. When compared to control, ITM patients had superior analgesia while using fewer opioids had significantly reduced intraoperative blood loss when ITM was administered before spinal fusion, and had a similar complication profile. While further studies are warranted to establish optimal dosing, these findings underscore the potential of ITM as a valuable addition to multimodal pain management.

Safety and efficacy of intrathecal morphine in early onset scoliosis surgery

Intrathecal morphine (IM) is a popular adjunct for pain management in spinal deformity surgery for idiopathic scoliosis. It has not been studied in patients with early onset scoliosis (EOS). We retrospectively reviewed EOS patients undergoing growth-friendly surgery who received IM or did not receive IM (non-IM). Data from initial insertion and final fusion procedures were studied. IM was not used for lengthening procedures, short procedures (<3 h), patients with significant underlying respiratory issues, paraplegia, unsuccessful access and anesthesiologist discretion. We assessed pediatric ICU (PICU) admission and IM complications (respiratory depression, pruritus and nausea/vomiting), time to first postoperative opiate, and pain scores. There were 97 patients including 97 initial insertions (26 IM and 71 non-IM) and 74 patients with final fusions (17 IM and 57 non-IM). The first dose of opioids following insertion and final fusion occurred at 16.8 ± 3.8 and 16.8 ± 3.1 h postoperatively in the IM group compared to 5.5 ± 2.8 and 8.3 ± 3.2 h in the non-IM group, respectively ( P  < 0.001). Postoperative pain scores were lower in the IM groups ( P  = 0.001). Two patients with IM developed mild respiratory depression following initial insertion ( P  = 0.01) but did not require PICU admission. The rate of respiratory depression was not different between the final fusion groups. There was no difference between pruritus and nausea/vomiting at the final fusion. Preincision IM can provide well-tolerated and effective initial postoperative analgesia in select children with EOS undergoing spinal deformity surgery.

Intrathecal Drug Delivery for the Treatment of Cancer-Associated Chronic Pain in Children

OBJECTIVES

Management of refractory cancer-associated pain can be particularly challenging. Regional anesthesia is an alternative modality to treat acute and chronic refractory pain. Intrathecal (IT) drug delivery of opioids and other adjuncts has been used to treat refractory cancer-associated pain. This method has been shown to be relatively safe and effective, often associated with fewer systemic side effects when compared to oral or IV opioid administration. While intrathecal drug delivery systems (IDDS) are regularly used in the adult cancer population for the treatment of refractory, chronic pain, there is limited evidence of similar use in the pediatric setting.

MATERIALS AND METHODS

We performed a systematic review using conventional Preferred Reporting Items for Systematic Reviews and Meta-Analyses methodology to identify studies reporting IT drug delivery for the treatment of pediatric cancer-related pain. The primary outcome was satisfaction with analgesia categorized as "satisfactory" or "unsatisfactory." Functional benefits, previous systemic pharmaceutical interventions, previous non-IT regional interventions, indication for IT drug delivery, IT drugs used, and method of delivery were collected.

RESULTS

A total of 11 studies were identified, describing 16 patients with cancer-related pain treated with IT drug delivery. The average age of the cohort was 12.25 years, with ages ranging from 3 to 19 years. Most patients were adolescent (10/16). All patients had cancer diagnoses, with most patients suffering from solid tumor pain (14/16). Nearly all patients achieved satisfactory analgesia through IT drug delivery (15/16) and most reported functional benefits in addition to analgesia (13/16). Majority received IT drugs via external catheters (9/16). One severe complication of respiratory depression was reported, which resolved following naloxone administration.

CONCLUSIONS

There exist children with cancer whose pain is refractory to the standard approaches and may benefit from IT drug delivery. The existing data, although limited and of low tier evidence, suggest that IT drug delivery has been effective in the pediatric cancer population.