Although most women look forward to the day of their newborn’s delivery with excitement, this enthusiasm is often quickly tempered by the discomforts of labor. Although there are many techniques that can be employed to help deal with pain in labor, perhaps one of the most effective interventions is epidural anesthesia.
An “epidural” is an abbreviation for epidural anesthesia which is a type of regional anesthesia where pain signals traveling from the contracting uterus to the brain are blocked. It involves the placement of a small tube through the patient’s back that sits on top of the covering of the spinal cord called the dura mater. Through this small tube, an anesthetic mixture of medication is administered to help the patient be comfortable while in labor.
An epidural is usually placed by an anesthetist or anesthesiologist who has had special training in regional anesthesia and performs these procedures on a regular basis. With the patient either sitting or lying on her side, the patient is asked to curl up into a ball to help open up the spaces in between the vertebral bones of the spine. The lower portion of the back is marked at the level where the epidural will be placed and then cleansed with an antiseptic wash to prevent infection. Being careful to keep the area sterile, the skin is first numbed with local anesthetic before inserting the needle into the intervertebral space. This is advanced slowly until a loss of resistance occurs as the numbing medicine is introduced into the space just on top of the dural covering of the spinal cord. A tiny catheter the diameter of a pin is then introduced through this needle so additional medicine can be administered throughout labor to continue to keep the patient comfortable. The epidural catheter is then secured to her back with tape so it does not become dislodged.
In general, epidural anesthesia is considered much safer for the mother and her unborn baby than general anesthesia where the patient is put to sleep. In addition, an epidural does not cause sedation of the mother and the fetus commonly seen with the administration of intravenous narcotics also used during labor for pain management. However, there are some small risks that can occasionally occur with use of epidural anesthesia that we would like to discuss further.
Low blood pressure. The most common side effect of regional anesthesia like an epidural is a transient drop in a patient’s blood pressure. If this occurs, intravenous fluids and medications can be given to help promptly correct this, but a temporary sensation of nausea may occur, rarely associated with vomiting.
Nerve irritation or damage. As the epidural catheter is placed, an occasional irritation of a nerve may result in a sharp, fleeting pain down one or both legs. If this occurs, the catheter is merely withdrawn and re-advanced to avoid the previously irritated nerve. Rarely, a blood clot can form around the epidural site, compressing the spinal cord and resulting in nerve problems. Permanent nerve injury, such as paralysis, although theoretically pos- sible is exceedingly rare.
Lack of anesthesia. Even in the most experienced hands, epidurals may not always work effectively in alleviating a patient’s labor discomforts. Frequently, this may be due to a patient’s unique spinal anatomy. If this occurs, redosing the epidural with additional medication may prove helpful, but if not, the epidural is often replaced.
Intravenous epidural placement. Rarely, the epidural catheter can enter a vein during placement, resulting in possible seizures if the medication is administered. Venous placement is generally known to the anesthesiologist or anesthetist when this occurs since they will see blood in the syringe before administering the medication and know to replace the epidural.
Leaking cerebrospinal fluid. Since the placement of an epidural involves the finesse of placing a catheter by a sense of feel, occasionally the catheter can track slightly beyond the target area of the epidural space and enter the dura, allowing cerebral spinal fluid to leak. When this occurs, it is often known by the anesthetist or anesthesiologist who may choose to
leave the epidural in place for a few additional hours after delivery hoping this may seal spontaneously. If it does not, the patient may begin to experience headaches when sitting up which promptly improve after laying down. These headaches are referred to as post-dural puncture headaches occurring in one to two percent of epidural cases. This is most often easily corrected with intravenous fluids, but occasionally may require an injection of a small amount of the patient’s own blood in the area of the leak to plug this hole. This is referred to as a blood patch.
Infection. Although ex- tremely rare and seldom heard of, infections are also theoretically possible with any
procedure where foreign items such as needles are inserted into a patient’s body.
Since pain is very subjective, the anesthesiologist or anesthetist arguably has one of the more challenging jobs in the hospital. Every patient wants to feel “just right” after their epidural is placed and dosed with medication. “Just right” however means different things to different people. Some individuals prefer to be completely pain free while others prefer to feel some pain, just not the severe pain they have been feeling.
Communicate what your preferences are to your anesthetist or anesthesiologist as to how “dense” you wish your block to be. In many hospitals, patients are given a small pump that can administer additional anesthesia medication on demand when the patient wishes, giving the patient control over her epidural’s effectiveness. Explain what your wishes are with regard to the degree of pain control you are hoping for and your anesthetist or anesthesiologist will be glad to accommodate your requests.
Scoliosis is the abnormal left or right curvature of a patient’s spine. Kyphosis is an abnormal front to back curvature of the spine. Since patients who suffer from scoliosis and kyphosis often have varying spinal anatomy, placement of an epidural may present the anesthesiologist or anesthetist with a challenge. Accordingly, it may prove beneficial to arrange a consultation during the third trimester with an anesthesiologist or anesthetist for patients with spine problems if they are planning on an epidural while in labor.
We hope this brief description of epidural anesthesia has provided you with the information you need to make an informed decision about what pain management options you prefer in labor. Although there are small risks associated with the placement of an epidural, in the experienced hands of an anesthetist or anesthesiologist, it provides a safe, reliable, effective option for pain relief during your delivery. If you have additional questions, please feel free to discuss them with your doctor.