Comparison of Analgesic Efficacy of Caudal Ropivacaine and Ketamine Vs. Ropivacaine and Midazolam in Paediatric Patients Undergoing Infraumbilical Surgery

Abstract

Introduction: Caudal analgesia is a part of multimodal approach to acute and chronic pain management in children. Pain is associated with increase pain perception in subsequent painful neurohormonal, behavioural responses which can be harmful. Caudal blockade is the commonest regional technique used in children. Objective: To assess the comparison of analgesic efficacy of caudal ropivacaine and ketamine vs ropivacaine and midazolam in paediatric patients undergoing infraumbilical surgery. Methods: A randomised controlled trial was conducted at Dept. of Anesthesia, tertiary care hospital in Dhaka, Bangladesh from January to June 2021. Total 60 paediatric patients undergoing infraumbilical surgery included. Each group comprises of 30 patients, age between one to seven years, either gender, 8 to 25 kg and ASA I to III. Paediatric patients of ASA status IV and V, emergency surgeries, local infection of the caudal area, history of allergic reactions to local anaesthetics, bleeding diathesis, preexisting neurological or spinal diseases, mental retardation, neuromuscular disorders were excluded from the study. Results: Total 60 Paediatric Patients included. The patients demographics, ASA classifications, base line mean values in SBP, DBP, MAP, PR, RR, SpO2 and temperature, and mean duration of surgery in the groups were comparable. From the distribution of surgeries done across the two groups, in group A RK 15 patients (50%) had herniotomy, 12 patients (40%) had orchidopexy and 3 patients (10%) had hypospadias repair. In group B RM, 16 patients (53.3%) had herniotomy, 9 patients (30%) had orchidopexy and 5 patients (16.7%) had hypospadias repair. Only 3 subject (10%) in group B experienced fever and vomiting p=0.36. The TTFAR for groups A 14.4±2.36 hours and group B 12.0±3.69 hours were respectively. The values were significantly different between groups A and B (p=0.02). Total postoperative acetaminophen consumption in 24 hours was 102.67±89.62 mg, 118.59±98.71 mg for groups A and B respectively. Postoperatively, the mean FLACC pain scores at 30 minutes, 2, 4, 6 and 12 hours; the corresponding p values across the two groups, p=0.13, 0.00, 0.00, 0.00 and 0.03, show statistically significant difference in the scores at 2, 4, 6 and 12 hours. Conclusion:The duration of postoperative analgesia along with time for first request of analgesic was comparatively superior in the Ropivacaine and ketamine combination rather than ropivacaine and midazolam without significant adverse effects or derangement in haemodynamic parameters. Despite unanswered questions exist, ketamine can be safely used as an adjuvant for caudal block in pediatrics for postoperative pain management to extend analgesic duration provided by local anesthetics alone with rare side effects. This adjuvant also decreases postoperative opioid consumption by prolonging the first analgesic requirement time.