Intra- versus postoperative initiation of pain control via a thoracic epidural catheter for lumbar spinal fusion surgery.

BACKGROUND: Thoracic epidural anesthesia (TEA) is one of the pillars of perioperative pain care. Particularly for spine surgery which causes significant postoperative pain TEA seems like an appealing option. However, beneficial effects of a TEA are questionable when the catheter is not used intraoperatively, a decision that is usually based on the surgeon's wish to perform immediate neurological examination postoperatively. METHODS: Forty patients undergoing transforaminal lumbar interbody fusion surgery (TLIF) were randomized into two groups. Patients received preoperative insertion of a TEA. For patients in the intraoperative group an epidural infusion was started preoperatively and maintained throughout. For patients in the postoperative group the epidural infusion was started once neurological examination had been performed. The primary outcome measure in this study was postoperative requirements of piritramide during the first two postoperative hours. Secondary outcomes involved postoperative pain numeric rating scale (NRS) scores, intraoperative opioid requirements, side effects and ability to perform direct postoperative neurological examination. RESULTS: Postoperative group patients required significantly more opioids both intra- and postoperatively (P=0.036 and P=0.039) and NRS scores were significantly higher on admission to recovery, at 30 and 60 min as compared to patients in the intraoperative group (P=0.013; P=0.004 and P=0.012). Early postoperative neurological examination was feasible in all patients in both groups. CONCLUSIONS: Epidural catheters used intraoperatively during TLIF are feasible, significantly reduce pain, intra- and postoperative use of opioids and do not influence the quality of neurological tests directly after the surgical procedure.