What Is an Epidural?

Epidural anesthesia refers to epidural space block anesthesia, that is, local anesthetic is injected into the epidural space to block the spinal nerve root and temporarily paralyze the dominating area. External block. According to the way of administration can be divided into single method and continuous method. According to the puncture site, it can be divided into high, middle, low and sacral block.

Epidural anesthesia

1. In order to prevent and treat total spinal anesthesia, tracheal intubation devices, oxygen supply equipment and other first-aid supplies must be prepared.

2. Strict disinfection.

3, puncture position

Local anesthetics used for epidural block should have the characteristics of strong dispersion, strong penetrability, low toxicity, short onset time, and long maintenance time. Local anesthetics currently in use are

(I) Factors Affecting the Block Plane

1. The larger the drug volume and injection speed volume, the faster the injection rate, and the wider the block range. On the contrary, the block range is narrower, but clinical practice has proved that rapid injection has a limited effect on expanding the block range.

2. Position and direction of the catheter When the catheter is to the head side, the drug is easy to diffuse to the head side; when it is to the caudal side, it can diffuse 1 to 2 segments to the caudal side, but it is still mainly to the head side. If the catheter is deflected to one side, unilateral anesthesia can occur, and occasionally the catheter gets stuck in the foramen, and can only block a few spinal nerve roots.

3. The patient's condition Infants, young people, and the elderly have a small epidural space. In late pregnancy, due to the compression of the inferior vena cava, the gap is relatively small, the drug is easy to spread, and the amount of medication must be reduced. Certain pathological factors, such as dehydration and insufficient blood volume, can accelerate the spread of the drug and should be used with extreme caution.

(Two) intraoperative management

Within 5 to 10 minutes after injecting a local anesthetic into the epidural space, dullness may appear in the skin dominating areas at the upper and lower segments of the puncture site. The blockage can be expanded to the expected range within 20 minutes, and the anesthesia is also complete. Acupuncture the skin and measuring pain can reveal the scope and effect of the block. In addition to sensory nerves being blocked, sympathetic and motor nerves are also blocked, which can cause a series of physiological disturbances. As with spinal anesthesia, the most common are blood pressure drops, respiratory depression, and nausea and vomiting. Therefore, attention should be paid during the operation

1. Systemic toxicity of local anesthetics

2.Into the subarachnoid space

3.Into the subdural space

4, the catheter is broken

5. Abnormal and extensive block (also known as total spinal anesthesia, clinical manifestations are no pain, hypotension, loss of consciousness, and respiratory arrest in all spinal nerve innervation areas. Symptoms usually appear within minutes after injection, and the heart can occur if treatment is not timely Stop.)

6, dural puncture and headache

7, nerve damage