203. Epidural pain catheter improves postoperative pain control following lumbar fusion compared to patient-controlled analgesia (PCA)

Abstract

<h3>BACKGROUND CONTEXT</h3> Postoperative pain control for patients in the hospital after lumbar spinal fusion can be quite challenging. Reliance on opioids postoperatively can predispose patients to tolerance and abuse. Multimodal pain control regimens have become the standard of postoperative care, though protocols tend to vary by surgeon and institution. The mainstay of pain control following lumbar spinal fusion surgery involves narcotic pain medication administered by patient controlled intravenous analgesia (PCA), which is typically supplemented by oral pain medications. One potential alternative to PCA is patient-controlled analgesia via epidural catheter. Surgeon-placed epidural catheters under direct visualization have previously been described for their simplicity, efficacy and time efficiency. <h3>PURPOSE</h3> After experiencing clinical success with the use of epidural catheters placed via the loss of resistance technique one- to three- levels above the proximal lumbar fusion level in postoperative care regimens,the senior author (TFA) embarked upon this prospective, randomized trial to assess the relative utility and complication rate of the epidural catheter method of pain management when compared to standard PCA narcotic administration for pain control after one- or two-level circumferential lumbar fusion surgery. <h3>STUDY DESIGN/SETTING</h3> The surgeries in the trial were performed by three surgeons in a university spinal surgery practice. Patients who enrolled agreed to be randomized to either the epidural catheter (EC) or the commonly practiced PCA arm of the study. A power analysis demonstrated that a sample size of 50 patients, using a level of significance of 0.05, would have a power of 0.97 to detect a 2-point difference in pain scores. <h3>PATIENT SAMPLE</h3> Fifty patients from the University spinal surgery practice were recruited to enter the study. Candidates for the study were patients undergoing one- or two-level instrumented lumbar fusion. Patients were randomized over a 10-month period into either the epidural (EA) or IV analgesia (PCA) groups, 27 to EA and 23 to PCA. <h3>OUTCOME MEASURES</h3> Preoperative pain scores, as well as daily postoperative pain scores were recorded. <h3>METHODS</h3> If randomized to the EC arm, an epidural catheter was placed by the surgeon just prior to wound closure, 1-3 levels above the most proximal level of the fusion. A 17-gauge Tuohy epidural needle was used with a loss-of-resistance syringe to locate the epidural space under fluoroscopy if deemed appropriate by the surgeon, and then the catheter was inserted through it. A bolus of 5cc of 0.25% bupivacaine was typically given at the time of catheter placement. Postoperatively, a continuous infusion was begun of 0.125% bupivacaine at 6 cc/hr combined with hydromorphone at 0.2 mg/hr. A patient controlled epidural demand dose of 25mcg of fentanyl with a 10-minute lockout period was also started. If randomized to the PCA group, patients were placed on a patient-controlled analgesia pump administering intravenous hydromorphone with a demand dose of 0.2-0.4 mg with a 10-15-minute lockout <h3>RESULTS</h3> Postoperative pain scores were statistically lower in the EC group on Days 1, 2 and 3: 2.13 vs 4.92 (day 1); 2.71 vs 4.52 (day 2); 3.13 vs 4.52 (day 3). Postoperative complications were similar between the EC and PCA groups. The incidence of nausea/vomiting were 56% and 74% (p=0.43) in EC and PCA groups, respectively, while postoperative symptomatic hypotension was seen in 8% of EC patients and 12% of PCA patients (p=0.67). <h3>CONCLUSIONS</h3> In this prospective, randomized study comparing the use of EC to PCA narcotic for pain control after one- and two-level lumbar fusions, a significant improvement in pain control was noted in the EC group with differences in minor side effects that did not reach statistical significance. Epidural anesthesia for postoperative pain control should be considered for patients undergoing lumbar fusion. <h3>FDA DEVICE/DRUG STATUS</h3> This abstract does not discuss or include any applicable devices or drugs.