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Epidural Nerve Blocks

By December 17, 2019 No Comments

Epidural anesthesia is well-known for its use for pregnant women during labor.1 One of the most common functions of epidural anesthesia is as a nerve block, which numbs spinal nerves and prevents pain signals from traveling to the brain.2 An epidural involves injecting a small amount of anesthetic into the epidural space of the lumbar spine, which is an area surrounding the spinal cord that contains fluid, fat and small blood vessels.1,3 In order for the anesthetic to last throughout the procedure or birth, an anesthesia provider may place a catheter into the epidural spine, allowing for continuous anesthesia administration.1 About 10 to 20 minutes after the initial injection, the nerves that carry pain signals to the brain will be blocked. Though patients will no longer feel pain in their lower body, they still may be able to feel pressure and may even be able to get up and walk around.2 Given its ubiquity and ease of administration, epidural anesthesia is a widely-used form of local anesthetic.4

Epidural anesthesia is used for abdominal, pelvic and lower extremity procedures, as well as thoracic procedures.4 It can be used to supplement general anesthesia and to provide postoperative analgesia.4 For procedures that require local anesthesia to the lower body, the anesthesiology practitioner may choose between spinal, epidural and combined spinal-epidural (CSE) anesthesia, which are all neuraxial anesthetics that can be used for many of the same surgeries.4 The differences between these types of anesthesia might affect the anesthesiologist’s choice, depending on the type of procedure or patient.4 For example, spinal anesthesia is usually administered as a single injection, thus limiting its effects to the duration of action of the injected drug.4 Meanwhile, epidural is usually administered via catheter, allowing for continuous anesthetic titration.4 Also, the anesthesia provider can choose the location of epidural administration in order to treat a variety of pain types. One study, conducted over 30 years ago by Catchlove and Braha, found that epidural anesthesia could be administered to the cervical spine (i.e., neck) to reduce chronic pain in the head and neck.5 Another article by Liu et al. emphasizes epidural anesthesia in the thoracic region for patients with coronary heart disease to increase their oxygen supply.6 Epidural anesthesia has functions in many surgical and obstetric contexts, and it is the anesthesiologist’s role to establish when its use is indicated.

In addition to its anesthetic function during a procedure, epidural anesthesia can also provide pain relief after surgery. An older study by Yeager et al. found that when compared to controls, patients who received epidural anesthesia and postoperative analgesia showed fewer postoperative complications, cardiovascular failures and major infections; reduced postoperative stress; and lower hospital costs.7 Liu et al.’s review states that postoperative epidural anesthesia may cause better cardiac outcomes.6 Yet another study by Schreiber et al. showed that epidural nerve blocks were more effective in reducing postoperative pain than were paravertebral nerve blocks.8 Finally, Bardia et al. found that combining epidural anesthesia with general anesthesia—as opposed to general anesthesia alone—reduced immediate postoperative events such as surgical reintervention, bowel ischemia, respiratory complications and dialysis.9 Epidural anesthesia has the potential to influence the postoperative period, which is crucial to improving patient outcomes after surgery.

Anesthesia providers use epidural anesthesia for many procedures that require numbing the lower body, including labor. Epidural anesthesia can also be effective in providing postoperative pain relief and reducing complications after surgery. Future research should compare the efficacy of anesthetics that can be administered epidurally. Additionally, studies should analyze the efficacy of combination methods such as CSE anesthesia and epidural-general anesthesia in different types of surgery.

1.         InformedHealth.org. Pregnancy and birth: Epidurals and painkillers for labor pain relief. Cologne, Germany: Institute for Quality and Efficiency in Health Care (IQWiG); March 22, 2018.

2.         WebMD.com. Epidural Nerve Blocks. What is an Epidural? 2019; https://www.webmd.com/back-pain/what-is-an-epidural#1-2.

3.         SPINE-Health. Epidural Space Definition. 2019; https://www.spine-health.com/glossary/epidural-space.

4.         Ituk U, Wong CA. Epidural and combined spinal-epidural anesthesia: Techniques. In: Maniker R, ed. UpToDate. Web 2019.

5.         Catchlove RFH, Braha R. The use of cervical epidural nerve blocks in the management of chronic head and neck pain. Canadian Anaesthetists’ Society Journal. 1984;31(2):188–191.

6.         Liu S, MD, Carpenter RL, MD, Neal JM, MD. Epidural Anesthesia and Analgesia: Their Role in Postoperative Outcome. Anesthesiology: The Journal of the American Society of Anesthesiologists. 1995;82(6):1474–1506.

7.         Yeager MP, Glass DD, Neff RK, Brinck-Johnsen T. Epidural anesthesia and analgesia in high-risk surgical patients. Anesthesiology. 1987;66(6):729–736.

8.         Schreiber KL, Chelly JE, Lang RS, et al. Epidural Versus Paravertebral Nerve Block for Postoperative Analgesia in Patients Undergoing Open Liver Resection: A Randomized Clinical Trial. Regional Anesthesia & Pain Medicine. 2016;41(4):460–468.

9.         Bardia A, Sood A, Mahmood F, et al. Combined Epidural-General Anesthesia vs General Anesthesia Alone for Elective Abdominal Aortic Aneurysm Repair. JAMA Surgery. 2016;151(12):1116–1123.