What is an epidural?
An epidural is a procedure that stops pain by injecting an anesthetic similar to the type that dentists use. The anesthetic bathes the lower spinal cord and prevents transmission of pain signals. A labor epidural numbs you from your belly button down. Epidurals for cesarean sections are stronger and reach to your breastbone. An epidural also interferes with the ability to move your legs and with certain autonomic nervous system functions such as sweating.
To prepare you for an epidural, nurses start an I.V. and administer about a quart of fluid. This is intended to prevent a fall in blood pressure, but low blood pressure continues to be the epidural’s most common, potentially serious side effect. Nurses apply a blood pressure cuff so that your blood pressure can be closely monitored. In many hospitals the cuff periodically inflates and records your pulse and blood pressure automatically. An epidural also requires continuous electronic fetal monitoring to pick up any epidural-caused problems with the baby’s heart rate. Finally, you either sit up on the side of the bed or lie on your side while your back is washed with antiseptic and covered with a sterile drape.
For the actual procedure, you arch your back like a “mad cat” or a rainbow. The anesthesiologist numbs the skin a little above waist level with local anesthetic and pushes a large needle through the ligament that connects two spinal vertebrae. You must hold absolutely still while the needle is in your back even if you have a contraction,and you will probably have one or two during this part of the procedure. Feeling carefully for the loss of resistance, the anesthesiologist guides the needle into the epidural space. This space lies beneath the ligament and outward of the two membranes that cover the spinal cord. The anesthesiologist performs one or more tests to check that the needle has neither pierced a blood vessel nor gone below the epidural space, problems that can cause life-threatening complications.