Diclofenac vs. Ropivacaine for Cesarean Section

Study Objective: To assess the analgesic efficacy of diclofenac or ropivacaine when administered via wound infusion.

Design: Prospective, randomized, double-blind, placebo-controlled study. Setting: Large referral hospital. Patients: 75 women recovering from Cesarean section performed via a Pfannenstiel incision.

Interventions: On completion of the surgical procedure, a 15 cm 19G infusion catheter (PAINfusor™, Baxter) will be placed below the fascia. According to a computer generated randomization schedule, patients will be divided into one of three treatment groups (n = 25).

• In Group Control water for injection will be administered.
• In Group Ropivacaine 0.2 % ropivacaine will be administered.
• In Group Diclofenac diclofenac (300 mg/240 ml of water for injection) will be administered.

During the first 6 postoperative hours, a co-investigator will administer "rescue" analgesia (10 ml bolus of infusion drug or rescue morphine). Thereafter, the catheter will be connected to an elastometric pump (LV 10 Infusor, Baxter) filled with either water for injection, ropivacaine 0.2 %, or diclofenac (300 mg/240 ml water for injection). The fluid will be administered as a constant infusion rate (10 mL/hr). Continuous wound infusion will be continued for the subsequent 18 postoperative hours. During this 18 hour period, subcutaneous morphine 4 mg will be administered on patient request for additional analgesia.

Measurements and Main Results: The following parameters will be assessed and recorded:

• Demographic data
• Surgical milestones(Anesthetic time, surgical time etc).
• Incidence of failed intrathecal anesthesia
• VAS for pain every 15 min during first 6 postoperative hours
• Time to first pain (intrathecal anesthesia to VAS > 60 mm)
• Number of infusion events (10 mL and 5 mL)
• Rescue morphine administration during first 6 postoperative hours.
• Subcutaneous morphine administration during subsequent 18 postoperative hours.
• VAS for pain.
• The incidence of nausea and vomiting.
• Patient satisfaction at 24 hours, postoperatively.

Inclusion criteria

• Patients undergoing Cesarean section

Exclusion criteria

A history of clinically significant disease:

• cardiovascular
• pulmonary
• hepatic
• renal
• neurologic
• psychiatric
• metabolic disease