comparison of dexmedetomidine and ketamine in serratus anterior plane block for postoperative pain control in thoracotomy patients: a randomized clinical trial

Background: postoperative pain control after thoracotomy is very important, and if not controlled, it can cause severe complications. objectives: this study aimed to compare dexmedetomidine and ketamine in serratus anterior plane block (sapb) in pain control after thoracotomy. methods: this randomized clinical trial was conducted on 74 patients aged 18 to 60 years old with american society of anesthesiologists (asa) class i or ii who were referred to imam khomeini hospital in ahvaz, iran, for thoracotomy and randomly divided into two groups. after surgery, the sapb with ultrasound-guided was performed. in the ropivacaine-ketamine (rk) group, ketamine 0.5 mg/kg and 0.4 cc/kg ropivacaine solution 0.25% and in the ropivacaine-dexmedetomidine (rd) group, in addition to 0.4 cc/kg ropivacaine 0.25%, dexmedetomidine 0.5 µg/kg was added. verbal numeric scale (vns), systolic blood pressure (sbp), diastolic blood pressure (dbp), respiratory rate (rr), heart rate (hr), and mean arterial blood pressure (map) were recorded. results: there was no significant difference in both groups in terms of demographic information (p < 0.05). the average vns was lower in the ketamine group than in the dexmedetomidine group; however, there was a significant difference only at 1, 12, and 24 hours after surgery (p < 0.05). there was no statistically significant difference between the two groups in terms of sbp and dbp, hr, and map. there was a significant difference in the rr in the two groups at 12 and 24 hours after the operation (p < 0.05). conclusions: dexmedetomidine and ketamine, which were used as supplements to ropivacaine for sapb in patients undergoing elective thoracotomy, reduced the pain intensity after thoracotomy; nevertheless, the intensity of pain reduction was more and more effective in the group receiving ketamine.