Ketamine versus pregabalin as an adjuvant to epidural analgesia for acute post-thoracotomy pain

Objective The aim was to compare analgesic effect of ketamine versus pregabalin as adjuvant to post-thoracotomy epidural analgesia in the National Cancer Institute. Patients and methods This randomized controlled trial involved 60 adults planned for thoracotomy under general anesthesia for management of lung cancer. They were randomly assigned into one of two groups. Group K (n=30) received three doses of ketamine 0.5 mg/kg intravenously, that is, after induction of anesthesia and at 6 and 30 h postoperatively. Group P (n=30) received oral pregabalin 150 mg 2 h before surgery and at 6 and 30 h postoperatively. The endpoints were pain reduction using visual analog score (VAS) score, frequency of rescue morphine doses, hemodynamic parameters, and adverse effects in the first 48 h. Results VAS score was significantly lower in ketamine group than that in the pregabalin group from 8 up to 48 h postoperatively. In group P, VAS score decreased after 16 h (P<0.001) and continued to decrease up to 48 h. Rescue analgesia was required after 2 h by 11 (36.7%) patients in group K and 15 (50%) patients in group P (P=0.297). The two drugs were accompanied by hemodynamic stability. Patients in group P were more sedated 2 h after surgery compared with those in group K (P=0.006). No cases of nausea and vomiting or psychological adverse effects related to ketamine use were recorded. Conclusion Ketamine and pregabalin are good alternatives for augmentation of the efficacy of thoracic epidural analgesia following thoracotomy in patients with lung cancer. Ketamine has the advantage of more rapid action and higher efficacy in addition to less sedation in early postoperative period.