Epidural anesthesia, also referred to as epidural analgesia or epidural block, is widely used in a variety of clinical settings. It may be used for any procedure beneath the nipple line during inpatient and outpatient surgery, during diagnostic procedures, in post-operative and chronic pain relief and to control pain during childbirth. Although associated with a high degree of safety, epidural anesthesia has some side effects.
Changes in Blood Pressure and Heart Rate
The most common side effect of epidural anesthesia is a drop in blood pressure due to dilation of blood vessels in the affected parts of the body. The anesthetic provider may choose to treat this with intravenous medications, such as ephedrine or phenylephrine--both of which increase blood pressure. Ensuring adequate hydration before administering the epidural is recommended to minimize the effects on blood pressure. Patients may also experience a decrease in heart rate after administration of epidural anesthesia. According to the American Pregnancy Association, this may also be treated with intravenous medications such as atropine, ephedrine or epinephrine, intravenous fluid and oxygen. An anesthesia provider will closely monitor a patient for side effects.
Nausea and Vomiting
Nausea and vomiting frequently accompany the drop in blood pressure experienced with epidural anesthesia. Treatment of low blood pressure may be all that's required to alleviate the nausea, but administration of IV anti-nausea medications such as Zofran and Compazine may also prove beneficial. Additional pain medications are sometimes used in conjunction with the epidural anesthetic. These include narcotic agents such as morphine, fentanyl and Demerol. The anesthetic provider may choose to eliminate or reduce the dosage of such medications to minimize the chance they may cause nausea and vomiting.
Backache and Headache
After placement of an epidural anesthetic, a patient may experience pain at the site of injection. Although normally mild and self-limited, it may last for a number of weeks. This may be due to a local inflammatory process, with or without muscle spasm, after the needle is inserted through subcutaneous tissue and ligaments. Treatment with warm and cold compresses, acetaminophen and non-steroidal anti-inflammatory medications, or NSAIDS, normally suffices. A patient should always report backache to a care provider, regardless of severity, as it may indicate a more insidious complication such a collection of blood, or hematoma. A severe headache within the first 12 to 72 hours after an epidural block is termed a postdural puncture headache, or spinal headache, caused by inadvertent puncture of the outer layer of the spinal column, or dura. As a result, fluid from the spinal column leaks out and causes pain that is throbbing or constant in nature. "This may be aggravated by sitting or standing, with a flat lying position providing some relief. Most headaches resolve spontaneously within 24 hours," John J. Nagelhout writes in "Nurse Anesthesia." Photophobia, which is an extreme sensitivity to light, and nausea may accompany the headache as well. Conservative treatment options include IV or oral fluid administration, or analgesics such as acetaminophen and caffeine, and an abdominal binder. In severe cases, an epidural blood patch may be performed, which is placement of a patient's own blood into the epidural space at the site of puncture. In the most extreme circumstance, a patient may need surgery to stop the leakage of spinal fluid.
Less Common Side Effects
Other less common complications or side effects experienced with epidural analgesia are related to the technique, amount and type of medication used, as well as to some uncontrollable factors. These include infection, allergic reactions and nerve damage, including paralysis, loss of bladder and bowel function and loss of sexual function. A person may also experience seizures, cardiac arrest or death.
References
- American Pregnancy Association: Epidural Anesthesia
- "Nurse Anesthesia: Third Edition"; Nagelhout, J.; 2005
- "Clinical Anesthesiology: Fourth Edition"; Mikhail, M., Morgan, E.; 2006
