Introduction:

Posterior spinal fusion (PSF) is a commonly performed orthopedic procedure to correct scoliosis in children. Continuous epidural analgesia (CEA) is a proposed means of providing analgesia following PSF. Whether a single epidural catheter with the tip in the upper thorax can provide adequate analgesia for PSF, which often spans the upper thoracic to lower lumbar regions, is unresolved in the literature.

Method:

In this single-center, retrospective study, we reviewed 69 consecutive patients undergoing PSF for adolescent idiopathic scoliosis (AIS) with CEA at our institution from October 1, 2020 to May 26, 2022. Data for the entire cohort was divided into two time intervals before and after epidural removal, group epidural (Epi) and group no epidural (No Epi). Daily intravenous and oral opioid morphine equivalents per kilogram (OME/kg) plus mean and maximal visual analogue pain scores (VAS 0-10) were recorded from post-anesthesia care unit (PACU) discharge to the end of postoperative day (POD) three. Results: 57 patients were included in the study. Opioid usage was 4.5 times greater in the 19 hours following removal of the epidural catheter when compared to the entire period (mean 65 hours) the epidural was in place (Group Epi 0.154 OME/kg vs Group No Epi 0.690 OME/kg, p<0.001). 51% (29/57) of patients did not require opioids (intravenous or oral) while the epidural was in place, all patients required opioids after epidural removal. Mean opioid usage while the epidural was in place was 9.3 OME, equivalent to approximately 6 mg of oxycodone. Mean and maximum pain scores increased significantly after removal of the epidural on POD 3 (mean pain score: Epi 3.4 (1.8) vs No Epi 4.1 (1.7); p<0.001) (max pain score: Epi 4.9 (2.5) vs No Epi 6.3 (2.1); p<0.001). Conclusions: This is the first study we are aware of to report pain scores and cumulative opioid requirements for PSF patients receiving CEA with a single epidural catheter before and after epidural removal. Opioid usage increased over four times in the 19 hours after epidural removal compared to the total opioid requirements while the epidural was infusing. Mean and maximum pain scores increased significantly after removal of the epidural on POD 3. This study firmly establishes that CEA with a single epidural catheter can provide profound analgesia for patients having PSF for AIS.