Epidural

An epidural refers to the administration of local anesthetic, often combined with an opioid, into the epidural space outside the dura mater of the spinal cord. This creates a regional nerve block that can provide anesthesia and/or analgesia to the lower body. Epidural anesthesia is distinct from spinal anesthesia, which injects into the subarachnoid space, and from intrathecal techniques.

Indications and use include relief of labor pain, intraoperative anesthesia for lower abdominal, pelvic, or lower limb surgery, and postoperative analgesia. A catheter is typically placed in the epidural space to allow continuous or intermittent dosing, and to enable patient-controlled epidural analgesia in some settings. Common drugs include local anesthetics such as bupivacaine or ropivacaine, often combined with opioids like fentanyl or morphine to enhance analgesia.

Technique overview a clinician with appropriate training inserts the needle into the lumbar region, usually between L2–L3 or L3–L4, with the patient in a seated or lateral position. Loss-of-resistance to saline or air helps identify the epidural space. After verifying catheter placement, a test dose checks for intravascular or intrathecal entry before proceeding with continuous infusion or episodic dosing.

Risks and contraindications are generally low but can include hypotension from sympathetic blockade, motor block, urinary retention, post-dural puncture headache, infection, hematoma, nerve injury, accidental intrathecal or intravascular injection, pruritus, and nausea. Absolute contraindications include patient refusal, infection at the insertion site, and certain coagulation abnormalities; other conditions may warrant caution or alternative techniques.

Alternatives include spinal anesthesia, combined spinal-epidural techniques, regional blocks, or systemic analgesia, depending on clinical goals and patient factors.