Management of Postoperative Pain With Preemptive Analgesia in Cesarean Section

Labor and delivery is a time of intense pain, often influenced by the psychological, emotional, social, cultural, and physical state of the parturient. Nowadays, delivery by Cesarean section is becoming more frequent. Females undergoing Cesarean section often wish to be awake postoperatively and to avoid excessive medications that will affect interactions with their newborn infant and visitors. However, Cesarean delivery is often associated with severe pain, requiring a well-planned analgesia regimen to ensure adequate patient comfort and satisfaction, early mobilization, and to decrease the hospital stay. An analgesic regimen may often include multiple doses of IV NSAIDs and opioids to adequately control the pain, and these costs add to the expenses of the hospital stay. Therefore, any intervention that leads to improvement in pain relief is worthy of investigation. Subcutaneous administration of local anesthetics can be a method of postoperative pain control after Cesarean section. Bupivacaine, a widely used local anesthetic, has been studied extensively in the past for the management of postoperative pain. The postoperative analgesic effects of subcutaneous wound infiltration prior to incision with bupivacaine have not been extensively studied in Cesarean delivery; hence, there may be a role in the management of pain relief when bupivacaine is administered at a specific time in surgery. Therefore, the present study is designed to assess the effect of preincisional skin infiltration with bupivacaine 0.25% versus placebo on postoperative pain relief after Cesarean delivery. 120 pregnant patients are randomized by means of the Drug Randomization Protocol (see below). The two groups are (A) control group in which preoperative wound infiltration with 10ml of 0.9% preservative-free normal saline is administered; and (B) in which preoperative wound infiltration with 10ml of 0.25% bupivacaine is administered. The primary end-point is postoperative pain. On arrival to the recovery room, pain intensity at rest is assessed by visual analogous scale ranging from 0 (no pain) to 10 (worst pain imaginable) and then 15, 30, 60 minutes and then 120 minutes after arrival in the recovery room.

Drug Randomization Protocol - All surgical staff is blinded to the study drug contents. A randomization checklist created by the Mercy biostatistician will be given to the scrub technician with a randomly generated list of 1s (saline) and 2s (bupivicaine) indicating the study drug to be administered. The scrub technician will assign a study drug to each patient as they arrive sequentially following the Study Randomization Checklist. The pharmacist will have the master list, indicating the contents of study drug 1 and 2. The scrub technician will order the study drug from the pharmacist by study name and number, eg. "Kathy Tom's study, drug 1." The pharmacist will be instructed not to indicate what the contents of the study related drug to the scrub technician or surgical staff and will send the drug up in a syringe labeled "Kathy Tom Study - Drug #" with all drug descriptive labeling covered.

The Study Randomization Checklist indicates the sequential participant number assigned to the patient on study entry, the corresponding study drug to be administered with a check box to indicate that the drug has been successfully administered (the box will not be checked if ordered and not administered), a column to record the date that the study drug has been administered, a column surgical to record the technician's initials that requested the study drug, and the medical record number of the patient. Sufficient information is included on the checklist to connect the study drug back to the patient if it becomes necessary.