The effectiveness of continuous epidural infusion of low-dose fentanyl and mepivacaine in perioperative analgesia and hemodynamic control in mastectomy patients

Study objectives To investigate, in mastectomy patients, the effectiveness of continuous cervical epidural block using a low-dose fentanyl infusion in combination with local anesthetics. Design Prospective, observational study. Setting 450-bed, university-affiliated hospital. Patients 21 ASA physical status I and II female patients undergoing modified radical mastectomy. Interventions An epidural catheter was inserted at the C₇-Th₁ interspace before the induction of anesthesia. Anesthesia was maintained using a low concentration of sevoflurane with nitrous oxide-oxygen (N₂O-O ₂). A mixture of 100 μg fentanyl and 49 mL of 1% mepivacaine was prepared, and 7 mL of this solution was epidurally injected before the initial incision. This same solution was continuously infused at a rate of 7 mL/hr (fentanyl 17.5 μg/hr) throughout the anesthesia, and at 2 mL/hr (fentanyl 5 μg/hr) postoperatively. Measurements and main results Intraoperative mean arterial pressure (MAP) and heart rate (HR), postoperative pain and analgesic use, and the frequency of postoperative side effects of anesthesia, including nausea, dizziness, and respiratory depression, were recorded. The protocol described provided stable intraoperative hemodynamic control with no or low-dose nicardipine infusion. Sufficient postoperative analgesia was achieved in 18 of 21 patients. One patient reported postoperative nausea, and no other side effects were reported. Conclusions Continuous epidural infusion of the low-dose fentanyl mixture described above provides adequate intraoperative hemodynamic control and postoperative pain relief, with a low rate of side effects in mastectomy patients.