A Comparative Study of the Analgesic Effects of Intravenous Ketorolac, Paracetamol, and Morphine in Patients Undergoing Video-assisted Thoracoscopic Surgery: A Double-blind, Active-controlled, Randomized Clinical Trial

BACKGROUND: Opioids are traditionally used as the drug of choice for the management of postoperative pain. However, their use is limited in patients undergoing Video-assisted thoracic surgery (VATS), due to their side effects, such as respiratory depression, nausea, and vomiting. AIM: In this double-blind active-controlled randomized study, we have compared the analgesic effects of ketorolac and paracetamol to morphine. METHODS: Patients were randomly chosen from a pool of candidates who were undergoing VATS and were divided into three groups. During the first 24 h postsurgery, patients in the control group received a cumulative dose of morphine 20 mg, while patients in two treatment groups received ketorolac 120 mg and paracetamol 4 g in total. Doses were administered as bolus immediately after surgery and infusion during the first 24 h. Patients' pain severity was evaluated by visual analogue scale rating (VAS) at rest and during coughing episodes. RESULTS: The average pain score at recovery time was 2.29 ± 2.13 and 2.26 ± 2.16 for ketorolac and paracetamol, respectively, and it was significantly lower than the morphine group with an average pain score of 3.87 (P = 0.003). Additionally, the VAS score during cough episodes was significantly higher in the control group throughout the study period compared to study groups. Comparison of mean morphine dose utilized as liberation analgesic (in case of patients had VAS >3) between three groups was not significantly different (P = 0.17). CONCLUSION: Our study demonstrates the non-inferiority of ketorolac and paracetamol to morphine in controlling post-VATS pain without causing any significant side effects. We also show that ketorolac and paracetamol are superior to morphine in controlling pain during 2 h postsurgery.