Absence of the Preemptive Analgesic Effect of Dextromethorphan in Total Knee Replacement under Epidural Anesthesia

給予Dextromethorphan肌肉注射對於硬膜外麻醉下執行全膝關節置換術可以降低術後疼痛，但不能提供前瞻性止痛

葉春長(Chun-Chang Yeh) ； 何善台(Shung-Tai Ho) ； 孔祥珣(Shang-Shung Kong) ； 吳慶堂(Ching-Tang Wu) ； 汪志雄(Chih-Shung Wong)

《Acta Anaesthesiologica Sinica》 38卷4期 (2000/12) Pp. 187-193

https://doi.org/10.6955/AAS.200012.0187

摘要

Background: Previous studies have shown that dextromethorph an (DM), a N-methyl-D-aspartate(NMDA) re-ceptor antagonist, produces a preemptive analgesic effect on post-operative pain. The aim of this study was to further examine the pre emptive analgesic effect of intramuscular (i.m.) DM injection on unilateral total k nee re-placement (TKR). Methods : Sixty-four ASA Ⅰ-Ⅲ patients scheduled for unilateral TKR surgery were randomly al located into three groups in a prospective double-blind manner. All patients received epidural anesthesia with out anypremedi-cation. An initial bolus dose of 2% lidocaine (15–20 mL) followed by a maintenance dose of 8-10 mL/h was decide d. Fentanyl (1.5 μg/kg) and diaz epam (2mg) were given i.v. before epidural catheter insertion. The epidural catheter was placed via the L2-L3 or L3-L4 interspace and advanced for 5 cm cephaladly. Patients received i.m. injection of 20 mg chlorpheniramine (CPM) before surgery as control (group C, n=22). For the study groups, patients we re given an i .m . injection containing 40 mg DM an d 20 mg CPM, before (group B, n=22) or after surgery (group A, n=20), respectively. Postoperation, patients received intravenous morphine by means of a patient controlled an-algesia (PCA) device for pain relief. The time to the first pull of PCA trigger , morphine consumption , worse pain scores (resting and incidental), and analgesics related side effects were recorded at 1, 2, 4, 8, 24, 48 and 72 h after surgery. Results: The time from the end of operation to the first PCA trigger were 31.2 ± 5.2 min in group C, 67.3 ± 1 1.1 min in group B(P＜0.05, com pared with group C) and 61.8 ± 7.2 min in group A(P＜0.05, compared with group C) respectively. The relevant pain sc ore at resting, observed at the 8 h postoperatively was re spectively 4.2 ± 0.1 in group C, 3.7 ± 0.2 in group B(P＜0.05, com pare d with group C) and 3.4 ± 0.2 in group A(P＜0.05, compared with group C); and at the 24 h was 3.1 ± 0.2 in group C, 2.4 ± 0.2 in group B(P＜0.05, compared with group C) and 2.5 ± 0.1 in group A(P＜0.05, compared with group C) respectively. There were no significant differences in actual morphine delivery and frequency of PCA triggering at all time among the three groups. Moreover , there was al so no significant statistic difference in morphine-associated side effects among the three groups. Conclusions : In the present study, we failed to observe any preemptive analgesic effect of DM (40 mg, i.m.) on postoperative pain in patients who received TKR under epidural anesthesia, however , DM given either before or after surgery augmented other analgesic (morphine) to offer a better pain relief.

關鍵字

Dextromethorphan ； 全膝關節置換術 ； 術後疼痛

並列摘要

Background: Previous studies have shown that dextromethorph an (DM), a N-methyl-D-aspartate(NMDA) re-ceptor antagonist, produces a preemptive analgesic effect on post-operative pain. The aim of this study was to further examine the pre emptive analgesic effect of intramuscular (i.m.) DM injection on unilateral total k nee re-placement (TKR). Methods : Sixty-four ASA Ⅰ-Ⅲ patients scheduled for unilateral TKR surgery were randomly al located into three groups in a prospective double-blind manner. All patients received epidural anesthesia with out anypremedi-cation. An initial bolus dose of 2% lidocaine (15–20 mL) followed by a maintenance dose of 8-10 mL/h was decide d. Fentanyl (1.5 μg/kg) and diaz epam (2mg) were given i.v. before epidural catheter insertion. The epidural catheter was placed via the L2-L3 or L3-L4 interspace and advanced for 5 cm cephaladly. Patients received i.m. injection of 20 mg chlorpheniramine (CPM) before surgery as control (group C, n=22). For the study groups, patients we re given an i .m . injection containing 40 mg DM an d 20 mg CPM, before (group B, n=22) or after surgery (group A, n=20), respectively. Postoperation, patients received intravenous morphine by means of a patient controlled an-algesia (PCA) device for pain relief. The time to the first pull of PCA trigger , morphine consumption , worse pain scores (resting and incidental), and analgesics related side effects were recorded at 1, 2, 4, 8, 24, 48 and 72 h after surgery. Results: The time from the end of operation to the first PCA trigger were 31.2 ± 5.2 min in group C, 67.3 ± 1 1.1 min in group B(P＜0.05, com pared with group C) and 61.8 ± 7.2 min in group A(P＜0.05, compared with group C) respectively. The relevant pain sc ore at resting, observed at the 8 h postoperatively was re spectively 4.2 ± 0.1 in group C, 3.7 ± 0.2 in group B(P＜0.05, com pare d with group C) and 3.4 ± 0.2 in group A(P＜0.05, compared with group C); and at the 24 h was 3.1 ± 0.2 in group C, 2.4 ± 0.2 in group B(P＜0.05, compared with group C) and 2.5 ± 0.1 in group A(P＜0.05, compared with group C) respectively. There were no significant differences in actual morphine delivery and frequency of PCA triggering at all time among the three groups. Moreover , there was al so no significant statistic difference in morphine-associated side effects among the three groups. Conclusions : In the present study, we failed to observe any preemptive analgesic effect of DM (40 mg, i.m.) on postoperative pain in patients who received TKR under epidural anesthesia, however , DM given either before or after surgery augmented other analgesic (morphine) to offer a better pain relief.

並列關鍵字

Dextromethorphan ； Total knee replacement ； Postoperative pain