Influência da morfina peridural na função pulmonar de pacientes submetidos à colecistectomia aberta

Abstract

BACKGROUND AND OBJECTIVES: Upper abdominal surgeries may cause postoperative respiratory dysfunction. The objective of this study was to evaluate the pulmonary function after laparoscopic and open cholecystectomies, with and without epidural morphine. METHODS: In this randomized, double-blind clinical trial, 45 pa- tients undergoing cholecystectomies were divided in three groups: GL, GA, and GAM, composed of 15 patients each. The GL group underwent laparoscopic surgery, while GA and GAM underwent open cholecystectomy, but the former received epidural morphine. Pre- and postoperative spirometry and arterial blood gases were performed. ANOVA was used to verify the hypothesis of equality of the means among the groups. When results were statistically sig- nificant, the Tukey test was performed. Paired test t Student was used to verify the hypothesis of equality within a group. A p < 0.05 was considered significant. RESULTS: The pre and immediately postoperative spirometry results were used to determine: a) forced vital capacity (FVC) in GL versus GA (p = 0.000) and GL versus GAM (p = 0.000); percentage of the reduction of FVC in GA versus GAM (p = 0.001); b) within each group: in GL, FVC (p = 0.020) and forced expiratory volume in 1 second (FEV 1 ) (p = 0.022); in GA, FVC (p < 0.001) and FEV 1 (p < 0.001); and in GAM, FVC (p = 0.007) and FEV 1 (p = 0.001). The arterial oxygen pressure (PaO 2 ) was reduced in all three groups. CONCLUSIONS: One can conclude that respiratory dysfunction was less severe in patients operated by laparoscopy and that epidural morphine reversed, partially, the postoperative ventilatory disturbances of open cholecystectomy.