Effect of perioperative oral amantadine on postoperative pain and morphine consumption in colorectal surgery

Simona Mărgărit¹, I. Acalovschi², Adriana Molnar³, Camelia Pascaru³, Anca Bălintescu³
1). Catedra ATI. Universitatea de Medicină şi Farmacie „Iuliu Haţieganu”. 2). Clinica ATI, Spitalul Clinic de Adulţi, Cluj Napoca 3). Medici rezidenţi ATI

Abstract

Background. The N-methyl-D-aspartat (NMDA) receptor plays an important role in the process of central sensitization and modulation of persistent postoperative pain. NMDA receptor antagonists may be useful in decreasing pain by preventing post surgical central sensitization. The aim of this study was to evaluate the effect of perioperative amantadine on pain and analgesic consumption in colorectal surgery.

Methods. After approval of the Ethics Committee of our institution and informed consent, 52 patients ASAI/II were included in the study. Patients scheduled to undergo colorectal surgery were given oral amantadine before and after surgery in a randomized, double-blind, placebo-controlled manner. After surgery, patients received intravenous patient-controlled analgesia with morphine for 24 h. The outcome measurement included: total morphine consumption, pain at rest and on movement and morphine requirements at 2, 4, 6, 12, 24 h after surgery.

Results. Total morphine consumption was significantly lower in the amantadine group (49.36 ± 12.29 mg) compared with placebo (65.60 ± 17.87 mg). Morphine consumption between intervals was significantly lower in the amantadine group compared with the placebo group immediately after surgery and at 4, 6, 12 hours postoperatively. Pain scores at rest were significantly lower in the amantadine group at 4 and 6 h after surgery. Pain scores on movement did not differ significantly between the groups. Amantadine did not reduce the incidence of morphine side effects.

Conclusions. Perioperative oral amantadine reduces pain and postoperative opioid consumption in colorectal surgery.

Key words: amantadine, NMDA receptor antagonist, central sensitisation, postoperative analgesia

Efectul amantadinei administrate perioperator asupra analgeziei cu morfină tip PCA în chirurgia abdominală

Jurnalul Român de Anestezie Terapie intensivă 2005 Vol.12 Nr.2, 107-113