Large study delivers message to expectant mothers: Epidural, spinal anesthesia safe choices for relieving pain

"The rates of complications are extremely low for obstetrical patients receiving anesthesia care, but there is always room for improvement," said Samir R. Jani, M.D., M.P.H., anesthesiology resident, Beth Israel Deaconess Medical Center, Boston. "This registry helps us better understand the practice of anesthesia in all settings in our health care system and identify differences that may help us improve patient safety. Our goal is to prevent complications from occurring and make anesthesia even safer."

The study analyzed data on 474,662 women who received anesthesia during labor, although adverse events (whether or not they occurred) were tracked in only a portion of patients. Overall, the rate of complications was 2,223 out of 80,093 cases (2.78 percent). The most common complication involved medications. This includes overdosing or underdosing, administration of unintended medication, or administration of expired medications. A common fear for women who are about to undergo neuraxial (spinal or epidural anesthesia) is a "spinal headache." The rate of this, known as a post-dural puncture headache, was extremely low, reported in only 161 of 83,786 cases (0.2 percent).

The vast majority of obstetric patients tracked in NACOR (88 percent) received either epidural or spinal anesthesia, or a combination of both. With an epidural, a tiny tube (called an epidural catheter) is inserted into the lower back to provide regional anesthesia, meaning only part of the body is affected by the medication. This allows the mother to participate in the birth of her child without some of the unwanted side effects associated with other forms of pain relief in labor. It takes some time for an epidural to take effect, but pain medication can be provided continually to the patient throughout labor. In a spinal the medication is delivered closer to the spinal cord which allows immediate pain relief, but eventually does wear off. The remaining 12 percent of patients received either general anesthesia or sedation.

NACOR is a data warehouse that has captured data on nearly 20 million anesthetics and millions of pain clinic procedures performed by physician anesthesiologists in the United States. The Anesthesia Quality Institute, an American Society of Anesthesiologists® affiliated organization, maintains NACOR and numerous other data registries with the goal of continual patient safety improvement.