Uso preventivo de cetamina nebulizada para controle da dor após amigdalectomia em crianças: estudo randômico e controlado

Abstract

ObjectivesThe administration of ketamine as nebulized inhalation is relatively new and studies on nebulized ketamine are scarce. We aimed to investigate the analgesic efficacy of nebulized ketamine (1 and 2mg.kg−1) administered 30min before general anesthesia in children undergoing elective tonsillectomy in comparison with intravenous ketamine (0.5mg.kg−1) and saline placebo. MethodsOne hundred children aged (7‐12) years were randomly allocated in four groups (n=25) receive; Saline Placebo (Group C), Intravenous Ketamine 0.5mg.kg−1 (Group K‐IV), Nebulized Ketamine 1mg.kg−1 (Group K‐N1) or 2mg.kg−1 (Group K‐N2). The primary endpoint was the total consumption of rescue analgesics in the first 24h postoperative. ResultsThe mean time to first request for rescue analgesics was prolonged in K‐N1 (400.9±60.5min, 95% CI 375.9‐425.87) and K‐N2 (455.5±44.6min, 95% CI 437.1‐473.9) groups compared with Group K‐IV (318.5±86.1min, 95% CI 282.9‐354.1) and Group C (68.3±21.9min, 95% CI 59.5‐77.1; p<0.001), with a significant difference between K‐N1 and K‐N2 Groups (p<0.001). The total consumption of IV paracetamol in the first 24h postoperative was reduced in Group K‐IV (672.6±272.8mg, 95% CI 559.9‐785.2), Group K‐N1 (715.6±103.2mg, 95% CI 590.4‐840.8) and Group K‐N2 (696.6±133.3mg, 95% CI 558.8‐834.4) compared with Control Group (1153.8±312.4mg, 95% CI 1024.8‐1282.8; p<0.001). With no difference between intravenous and Nebulized Ketamine Groups (p=0.312). Patients in intravenous and Nebulized Ketamine Groups showed lower postoperative VRS scores compared with Group C (p<0.001), no differences between K‐IV, K‐N1 or K‐N2 group and without significant adverse effects. ConclusionPreemptive nebulized ketamine was effective for post‐tonsillectomy pain relief. It can be considered as an effective alternative route to IV ketamine.