Effect of intraoperative dexmedetomidine on postoperative pain and pulmonary function following video-assisted thoracoscopic surgery

Acute postoperative pain following video-assisted thoracoscopic surgery (VATS) needs considerable attention, if untreated leads to chronic pain and postoperative lung dysfunction. Dexmedetomidine, α2 adrenoceptor agonist has shown promising results of opioid-sparing effects.The objectives of this study are to investigate the effect of dexmedetomidine on postoperative analgesia and pulmonary mechanics in patients undergoing VATS.This is a randomized controlled trial.We conducted a prospective, randomized, double-blind study on lung cancer patients undergoing VATS. Each patient received either dexmedetomidine or comparable volume of normal saline during the intraoperative period. In the recovery unit, postoperative visual analog scale (VAS) score, rescue analgesic requirements, arterial blood gas values, and pulmonary function tests were recorded.Data are analyzed using unpaired t-test, Mann-Whitney U-test, and Fischer's exact test. P < 0.05 was considered statistically significant.VAS scores were significantly lower (P < 0.05) in the dexmedetomidine group at rest, on coughing and on mobilization from supine to sitting position. The partial pressure of arterial oxygen measured in postanesthesia care unit was significantly higher in the dexmedetomidine group (88 ± 8.2 vs 78 ± 9.1 mmHg). Forced expiratory volume in 1 was significantly greater in the dexmedetomidine group compared to the control group on the first 2 postoperative days (P < 0.05). The length of hospital stay was significantly reduced by dexmedetomidine.Intraoperative dexmedetomidine administration improves the quality of analgesia and postoperative lung function in patients undergoing VATS.