Comparison of Intraoperative Low-Dose Ketodex and Fentanyl Infusion for Postoperative Analgesia In Spine Surgery: A Prospective Randomized Double-Blind Study.

ABSTRACT

STUDY DESIGN: Prospective randomized double-blind study. PURPOSE: To assess the analgesic effects of the combination of a low-dose ketamine and dexmedetomidine (ketodex) infusion and compare it with that of fentanyl for postoperative analgesia after spine surgeries. OVERVIEW OF LITERATURE Adequate pain management following spine surgeries is crucial. Approximately 57% of patients experience inadequate pain control in the first 24 hours following elective spine surgery, which is attributable to the extensive soft tissue and muscle damage. METHODS: The study included 60 patients graded American Society of Anesthesiologists I and II and scheduled for thoracolumbar spine surgery involving >3 vertebral levels. The patients were divided into two groups group KD (ketodex) and group F (fentanyl). The primary objective was to compare the postoperative analgesic requirements among the groups. The secondary objectives included a comparison of the intraoperative anesthetic requirements, postoperative pain scores, hemodynamic parameters, side effects of the study drugs, and the duration of post-anesthesia care unit stay of both the groups. RESULTS: Ketodex use prolonged the mean time to first rescue analgesia (22.00±2.30 hours vs. 11.69±3.02 hours, p <0.001) and reduced the requirement of rescue analgesics in the first 24 hours postoperatively compared to fentanyl use (70.00±8.16 µg vs. 113.31±36.65 µg, p =0.03). The intraoperative requirement of desflurane was comparable between the groups (p >0.05). The postoperative pain scores were significantly lower in the group KD than in group F at most timepoints (p <0.05). Patients in group KD had a shorter post-anesthesia care unit stay than group F did (p <0.001). CONCLUSIONS: Low-dose ketodex could be a safe substitute for fentanyl infusion when employed as an anesthetic adjuvant for patients undergoing thoracolumbar spine surgeries involving >3 vertebral levels to achieve prolonged analgesia without any opioidrelated side effects.