Dexamethasone and ketamine as adjuvants to bupivacaine for incisional infiltration in pediatric abdominal operations

Abstract

Background: Duration of analgesia with incisional infiltration using local anesthetics is short. Ketamine and dexamethasone are known for their role as adjuvants to local anesthetics. Objective: The present study compared the effects of ketamine and dexamethasone on the duration of analgesia when combined with bupivacaine for incisional infiltration in pediatric abdominal operations. Methods: A total of 150 children (1-8 years) undergoing open abdominal operations were randomized equally into three groups to receive incisional infiltration with Bupivacaine 0.25% 1 ml/kg (GpB), ketamine 1 mg/kg + bupivacaine (GpK), and dexamethasone 0.2 mg/kg + bupivacaine (GpD). Groups were compared for time for first analgesic dose (primary outcome), number of children requiring rescue analgesia; number of rescue analgesia doses; and FLACC scores (in the first 24 h postoperatively). Results: Time for first analgesic dose was significantly longer with ketamine (7.7 ± 2.41 h) and dexamethasone (7.46 ± 2.77 h) compared to bupivacaine (3.44 ± 1.34 h) (P < 0.001). FLACC scores were significantly lower in the dexamethasone and ketamine groups compared to bupivacaine at 4 h, 6 h, 8 h, 10 h and 12 h postoperatively (P < 0.001). Forty-eight children in the bupivacaine group required rescue analgesia which was significantly higher than the ketamine and dexamethasone groups (36 and 29 children respectively, P < 0.001. Conclusion: Combining either ketamine or dexamethasone with bupivacaine for incisional infiltration prolonged the duration of analgesia after pediatric abdominal operations.