[Comparative study of the effects of morphine and tramadol in the treatment of postoperative pain].

BACKGROUND: To compare morphine and tramadol in the treatment of postoperative pain (POP), using a system of Patient Controlled Analgesia (PCA). EXPERIMENTAL DESIGN: Randomised comparative study on 88 patients, undergoing general major surgical operations (gastrectomy, colectomy and hemicolectomy). PATIENTS: PCA i.v.: group M treated with morphine (at a dilution of 1 mg/ml) and group T with tramadol (at a dilution of 10 mg/ml). Loading dose: 0.05 mg/kg for the group treated with morphine and 0.5 mg/kg for the group treated with tramadol. Baseline infusion: 1.5 ml/h. Bolus on demand: 0.2 ml every 30 minutes. At T0, after 1 hour, 3 and 18 hours assessment of pain intensity, level of sedation, respiratory and cardiocirculatory parameters. After 18 hours assessment of the amount of drug administered, the number of boluses requested and given and any side effects. STATISTICAL ANALYSIS: ANOVA test, Student "t", chi 2. RESULTS: A statistically significant reduction in POP was found after 1 hour, 3 and 18 hours with no significant differences between the two groups. No statistically significant differences in cardiocirculatory or respiratory parameters or level of sedation were found. Few side effects were observed. CONCLUSIONS: Tramadol determines pain relief similar to morphine, with the advantage that it does not lead to abuse, tolerance or addiction.