Aims and Objectives: To compare the total bupivacaine consumption per hour of labor and the degree of motor block using the Modified Bromage score at regular intervals throughout labor.
Study Design: The study was a prospective, randomized, comparative study.
Materials and Methods: We included 50 patients, ASA physical status I, nulliparous women at term and cervical dilation < 4 cm admitted at our hospital for spontaneous labor.
Patients were divided into two groups Group A and B. Epidural analgesia was initiated with 10 ml 0.125% Bupivacaine and maintained with solution of 0.0625% Bupivacaine and Fentanyl 2 μg/ml in both groups. Group A (25 patients) received intermittent epidural bolus 10 ml every hour beginning 45 minutes after the initial dose. Group B (25 patients) received continuous infusion 10 ml/h, beginning immediately after the initial dose.
Statistical Analysis Used: Data were analysed by Unpaired ‘t’ test and 2 value applied. A value of P<0.05 was regarded as statistically significant.
Results: The median adjusted bupivacaine consumption per hour of delivery was in the first group 10.4 mg (9.4 - 12.6mg) and 8.6 mg (6.9 - 10.2mg) in the second group. There was significant difference between the two groups in the percentage of patients requesting manual bolus doses for breakthrough pain (58% intermittent epidural bolus vs 38% continuous epidural infusion) and in the need for multiple boluses (18% intermittent vs 11% continuous). Motor block was registered in only 2 patients (5.2%) in the second group (Modified Bromage 1)
Conclusion: Maintenance of epidural analgesia with continuous epidural infusion compared with intermittent epidural bolus top up decreased bupivacaine consumption without decreasing patient comfort or satisfaction.