title: Comparative effect of intraoperative propacetamol versus placebo on morphine consumption after elective reduction mammoplasty under remifentanil-based anesthesia: a randomized control trial [ISRCTN71723173].
abstract: BACKGROUND: Postoperative administration of paracetamol or its prodrug propacetamol has been shown to decrease pain with a morphine sparing effect. However, the effect of propacetamol administered intra-operatively on post-operative pain and early postoperative morphine consumption has not been clearly evaluated. In order to evaluate the effectiveness of analgesic protocols in the management of post-operative pain, a standardized anesthesia protocol without long-acting opioids is crucial. Thus, for ethical reasons, the surgical procedure under general anesthesia with remifentanil as the only intraoperative analgesic must be associated with a moderate predictable postoperative pain. METHODS: We were interested in determining the postoperative effect of propacetamol administered intraoperatively after intraoperative remifentanil. Thirty-six adult women undergoing mammoplasty with remifentanil-based anesthesia were randomly assigned to receive propacetamol 2 g or placebo one hour before the end of surgery. After remifentanil interruption and tracheal extubation in recovery room, pain was assessed and intravenous titrated morphine was given. The primary end-point was the cumulative dose of morphine administered in the recovery room. The secondary end-points were the pain score after tracheal extubation and one hour after, the delay for obtaining a Simplified Numerical Pain Scale (SNPS) less than 4, and the incidence of morphine side effects in the recovery room.For intergroup comparisons, categorical variables were compared using the chi-squared test and continuous variables were compared using the Student t test or Mann-Whitney U test, as appropriate. A p value less than 0.05 was considered as significant. RESULTS: In recovery room, morphine consumption was lower in the propacetamol group than in the placebo group (p = 0.01). Pain scores were similar in both groups after tracheal extubation and lower in the propacetamol group (p = 0.003) one hour after tracheal extubation. The time to reach a SNPS < 4 was significantly shorter in the propacetamol group (p = 0.02). The incidence of morphine related side effects did not differ between the two groups. CONCLUSIONS: Intraoperative propacetamol administration with remifentanil based-anesthesia improved significantly early postoperative pain by sparing morphine and shortening the delay to achieve pain relief.
authors.affiliation: Service d'Anesthésie-Réanimation, Hôpital Henri Mondor, AP-HP, Université Paris XII, 51, avenue du Maréchal de Lattre de Tassigny, 94010 Créteil, France. michele.binhas@hmn.ap-hop-paris.fr
authors.forename: Michèle
authors.initials: M
authors.lastname: Binhas
authors.forename: François
authors.initials: F
authors.lastname: Decailliot
authors.forename: Saïda
authors.initials: S
authors.lastname: Rezaiguia-Delclaux
authors.forename: Powen
authors.initials: P
authors.lastname: Suen
authors.forename: Marc
authors.initials: M
authors.lastname: Dumerat
authors.forename: Véronique
authors.initials: V
authors.lastname: François
authors.forename: Xavier
authors.initials: X
authors.lastname: Combes
authors.forename: Philippe
authors.initials: P
authors.lastname: Duvaldestin