Eficacia analgésica entre dos concentraciones de Bupivacaína en mujeres en trabajo de parto. Ensayo clínico controlado aleatorizado triple ciego / Analgesic efficacy of two concentrations of bupivacaine in women in labor: Randomized, controlled, triple blind clinical trial

ABSTRACT

Introduction: Epidural analgesia is the safest and most effective method for the treatment of pain during childbirth. Epidural bupivacaine provides excellent analgesia for labor and remains the most widely used local anesthetic in obstetric anesthesia. Objective: To evaluate the analgesic efficacy of two concentrations of bupivacaine in women in labor. Methods: 114 patients in labor with term pregnancy were included in the study They were grouped randomly into two groups patients who received bupivacaine at 0.125% (group A) and those who received 0.25% bupivacaine (group B). Patients in group A received a bolus injection of 10 ml of 0.125% bupivacaine. The patients in group B received a bolus of 10 ml bupivacaine 0.25%. Pain intensity according to VAS, blood pressure, heart rate, respiratory rate, and the degree of motorblock was assessed usingthe Bromage scale at different periods of time. Results: Demographic characteristics and parity were compared with no statistically significant differences found. By comparing the values of the VAS measure at 0, 15, 30, 60 and 90 min, statistically significant differences in favor of the group with 0.25% bupivacaine were found with decreased pain perception after 30 min, p-value = 0.02. No differences in arterial pressure, heart rate and respiratory rate were found between the two groups. Conclusion: The concentration of 0.25% bupivacaine has greater analgesic efficacy compared to 0.125% bupivacaine.