P201 Comparison of the efficacy of dexmedetomidine versus ketamine as an adjunct to ropivacaine for scalp block during awake craniotomy surgery – a clinical comparative study

Please confirm that an ethics committee approval has been applied for or granted: Yes: I’m uploading the Ethics Committee Approval as a PDF file with this abstract submissionBackground and Aims Scalp blocks are pivotal in facilitating patient comfort and analgesia during awake craniotomy procedures. This study aimed to compare the analgesic efficacy and safety of dexmedetomidine versus ketamine as adjuvants to 0.5% ropivacaine for scalp block. We hypothesised that ketamine, administered at a dose of 0.5 mg/kg, would demonstrate non-inferiority to dexmedetomidine in prolonging the duration of analgesia and enhancing postoperative pain management in awake craniotomy surgery for brain tumours. The primary outcome was time to first rescue analgesia (NRS ≥4). Secondary outcomes included onset of sensory block, intraoperative haemodynamics, sedation scores (RASS), postoperative pain scores (NRS), PACU discharge time, total 24-hour analgesic requirement, and incidence of adverse events.Methods This was a prospective, randomised, double-blinded, interventional trial conducted in 46 adult patients undergoing elective awake craniotomy. After institute ethical clearance (IEC/INT/2023/MD-1323) and CTRI Registration (CTRI/2024/01/061259), patients were allocated into two groups: Group RD (ropivacaine 0.5% + dexmedetomidine 1 µg/kg) and Group RK (ropivacaine 0.5% + ketamine 0.5 mg/kg). The Scalp Block was given by the landmark technique.Results The median duration of analgesia was significantly longer in Group RK (18.67 hours) compared to Group RD (14.67 hours; p < 0.001). Sensory block onset was similar in both groups (p = 0.906). Group RK demonstrated higher intraoperative blood pressures, while Group RD had a higher incidence of respiratory depression (39.1% vs 8.7%; p = 0.016). No significant differences were noted in sedation depth, incidence of psychosis, hypotension, bradycardia, or PONV. Group RK had a longer PACU stay (p = 0.015).Abstract P201 Figure 1Assesment of primary outcome in groups RD and RKConclusions Ketamine (0.5 mg/kg) is not inferior to dexmedetomidine (1 µg/kg) as an adjuvant to ropivacaine 0.5% for scalp block in awake craniotomy. It provides prolonged postoperative analgesia with a lower risk of respiratory depression, making it a viable alternative in clinical practice.