Pre-emptive Analgesia: The Effect of Low-Dose Ketamine on the Postoperative Pain after Circumcision with Unilateral Hydrocelectomy in Children / 대한마취과학회지

Backgrounds: Brief noxious stimuli are found to produce long-lasting neuronal sensitization. This cumulative depolarization results from the activation by glutamate of N-methyl-D-aspartic acid (NMDA) receptor. Ketamine at subanesthetic doses blocks the channel associated with the NMDA receptor. The aim of this study was to investigate the pre-emptive effect of ketamine in children after circumcision with unilateral hydrocelectomy. MATERIALS AND METHODS: We have compared the effect of preoperative ketamine (0.3 mg/kg) in a double-blind, randomized study, which was approved by the local Ethics Committee. Informed consents were obtained from their parents. After induction of anesthesia, patients were allocated randomly to receive a ketamine (n=20) or placebo (n=20) intravenously before surgery. Postoperative pain was rated on a faces scale for the first 24 hours. If pain occurred, children received tiaprofenic acid in a dose related to body weight. The cumulative pain score, the time of the first requirement of analgesics, and total requirement of analgesics for 24 hours were also checked. RESULTS: The pain scores at 4, 5, 6, 7, 8, 9, and 12 hours after operation were significantly low in ketamine group. The cumulative pain scores for the first 8 hours and the total requirements of analgesics were significantly low in ketamine group. The time of the first requirement of analgesic was significantly delayed in ketamine group. CONCLUSIONS: Preoperative ketamine in the pediatric circumcision with unilateral hydrocelectomy is effective on the reducing the intensity of the postoperative pain. The results of this study support the theory of pre-emptive analgesia of ketamine.

Analgesic Effects of Preoperative Versus Postoperative Tiaprofenic Acid in Pediatric Tonsillectomy & Adenoidectomy / 대한마취과학회지

BACKGROUND: The aim of this study was to investigate the pre-emptive effect of preoperative intravenous tiaprofenic acid in children aged 4~11 years after tonsillectomy and adenoidectomy. METHODS: We compared in 45 children the effect of preoperative with postoperative tiaprofenic acid (5 mg/kg) on pain after tonsillectomy and adenoidectomy, which was approved by Ethics Committee. Informed consents were obtained from all their parents. After induction of anesthesia, patients were allocated randomly to receive a tiaprofenic acid intravenously either before (n=15) or immediately after (n=15) surgery. The control group was received saline (n=15). Postoperative pain was rated on a faces scale for postoperative 48 hours. Tiaprofenic acid was given when patient complained pain. The cumulative pain score within 3 hours and 48 hours, time to the first analgesic administration, total requirement of analgesics for 48 hours and the first time of swallowing 50 ml water were checked. RESULTS: Postoperative pain score of the preoperative group was significantly lower than the postoperative group at 9, 42, and 48 hours after operation. The cumulative pain scores during the first 3 hours were 15+/-4 (p <0.05 vs postoperative), 21+/-7 and 22+/-5 in pre, postoperative and saline groups respectively. The cumulative pain scores for 48 hours were 40+/-18 (p <0.05 vs postoperative), 61+/-17 and 63+/-18 in pre, postoperative and saline groups respectively. The times of the first swallowing were 6 (5~6)(p <0.05 vs postoperative) hours, 7 (6.7~9)hours, and 8 (4.5~8.7)hours after operation in pre, postoperative, and saline groups respectively. CONCLUSIONS: Preoperative tiaprofenic acid in the tonsillectomy and adenoidectomy was effective on the reducing the intensity of the postoperative pain. The time to the first swallowing was shorter in the preoperative than postoperative group. The results of this study support the theory of pre-emptive analgesia.

Comparison of Preoperative with Postoperative Tiaprofenic Acid on Pain after Adult Local Tonsillectomy / 대한마취과학회지

BACKGREOUND: The aim of this study was to compare the pre-emptive effect of preoperative with postoperative tiaprofenic acid in adult local tonsillectomy. METHODS: We compared in forty adults the effect of preoperative with postoperative tiaprofenic acid on pain after tonsillectomy in a double-blind, randomized study, which was approved by the Ethics Committee. Informed consents were obtained. Patients were allocated randomly to receive a tiaprofenic acid (200 mg) intravenously either before (n=20) or immediately after (n=20) surgery. Postoperative pain was rated by self-rating visual analog scale for the first 24 hours. Tiaprofenic acid (200 mg) was given when patient complained pain. Time to the first analgesic administration, total requirement of analgesics for 48 hours and the first time of swallowing 100 ml water were checked. RESULTS: Postoperative 1 hour pain score of the preoperative group was significantly lower than postoperative groups (p<0.05). Times to the first analgesic administration, the total requirement of analgesics for 48 hours and the times of the first swallowing of 100 ml water were not significantly different between the two groups. CONCLUSIONS: Preoperative intravenous tiaprofenic acid (200 mg) in adult local tonsillectomy was effective on the reducing the intensity of the postoperative pain only 1 hour after operation. The use of preoperative tiaprofenic acid in adult local tonsillectomy was associated with a more calm recovery. The results of this study do not support the theory of preemptive analgesia.