Women who deliver their babies via cesarean section (C-section) are less likely to need opioids to manage post-delivery pain if they receive ongoing epidural analgesia (pain relief) that they can control, suggests first-of-its kind research presented at the ANESTHESIOLOGY® 2018 annual meeting.

Researchers found the longer patient-controlled epidural analgesia (PCEA) remained in place after C-section, the less likely the woman was to use oral opioids. PCEA helps the new mother manage the most severe pain, which occurs in the first two or three days after the procedure, typically spent in the hospital, they note.

“During the time the women studied used PCEA for their pain relief, they didn’t need oral opioids,” said Gilbert J. Grant, MD, associate professor of anesthesiology at the New York University (NYU) School of Medicine and director of obstetric anesthesia at NYU Langone Health. “One in four used no oral opioids even after stopping the epidural.”

C-sections may be performed under a local anesthetic given via spinal or epidural techniques. Most US hospitals use spinal anesthesia for planned C-sections. At the time the spinal is performed, the physician anesthesiologist injects a local anesthetic and a small dose of morphine into the spinal fluid. The morphine provides about 18 hours of pain relief after surgery, but women recovering from C-section may have significant surgical pain that lasts for several days. In most cases, after the spinal morphine effect wears off, women take oral opioids to manage their pain.

At the researchers’ institution, nearly all C-section patients have an epidural catheter (a tiny flexible tube) inserted into their lower back as part of their anesthesia. These patients do not receive spinal morphine. Instead, pain medication that numbs the abdomen is administered after surgery through the epidural catheter. The patient can “fine-tune” the amount of pain relief she desires by simply pushing a button. The PCEA can continue to relieve pain long after the commonly used spinal morphine wears off. Because the local anesthetic dose in PCEA is so low, muscle strength is not affected, so the mother is able to walk.

The study included 576 women who had planned C-sections and received PCEA during 2017. Researchers analyzed postoperative opioid use in the women and found that while PCEA was in place, the median quantity of oral opioids used was 0 mg. The researchers reported that overall, PCEA remained in place for a median of 43 hours after delivery. The longer the women were on PCEA, the fewer opioids they needed after it was stopped: each hour of PCEA resulted in a 0.33 mg decrease in the consumption of oxycodone, an oral opioid. The 25% of women who did not use any oral opioids, even after PCEA was stopped, used the epidural for a median of 44.9 hours.

Dr. Grant noted that while the routine US practice is to use epidurals only for labor, PCEA after C-section has many advantages, including: ability to be maintained for as long as the patient is in the hospital; improved movement in the intestines (which reduces constipation); giving the mother a sense of control and; a reduced need for oral opioids, as seen in the study.

In addition to a risk for dependence, oral opioids have a number of side effects that can be particularly problematic for new mothers such as drowsiness, nausea, vomiting, itching and constipation.