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.