Epidural anesthesia

When neuraxial anesthesia (epidural/spinal anesthesia) or spinal puncture is employed, patients who are anticoagulated or scheduled to be anticoagulated with low molecular weight heparins (LMWHs) or heparinoids for prevention of thromboembolic complications are at risk of developing an epidural or spinal hematoma, which can result in long-term or permanent paralysis. 

Local anesthetics are used for topical anesthesia, local infiltration, peripheral nerve block, paravertebral anesthesia, intravenous block also known as regional anesthesia, epidural block, and spinal i.e. subarachnoid blockade. The local anesthetics may be divided into two main groups, the esters and the amide-type agents. 

Brachial plexus anesthesia Buccal anesthesia Caudal anesthesia Cervical plexus anesthesia Dental anesthesia Digital anesthesia Epidural anesthesia Intercostal nerve anesthesia Interpleural anesthesia Intra-articular anesthesia Intradermal anesthesia Intrathecal (spinal) anesthesia Intravenous regional anesthesia Laryngeal anesthesia Lumbar plexus anesthesia Nasal anesthesia Neck anesthesia Obstetric anesthesia Ocular anesthesia Oropharyngeal anesthesia Otic anesthesia Paravertebral anesthesia Perianal anesthesia Peritonsillar anesthesia Respiratory anesthesia Sciatic nerve anesthesia Stellate ganglion anesthesia... 

Unless otherwise indicated, values are for infiltrative anesthesia. Epidural administration in cesarean section. 

Mepivacaine HCl 1 %, 2 % injection solution in sterile package Local infiltration anesthesia, epidural block... 

A conduction block is a type of regional anesthesia produced by injection of a local anesthetic drug into or near a nerve trunk. Examples of a conduction block include an epidural block (injection of a local anesthetic into the space surrounding the dura of the spinal cord) a trails sacral (caudal) block (injection of a local anesthetic into the epidural space at the level of the sacrococcygeal notch) and brachial plexus block (injection of a local anesdietic into the brachial plexus). Epidural, especially, and trailssacral blocks are often used in obstetrics. A brachial plexus block may be used for surgery of the arm or hand. 

Volk T, Schenk M, Voigt K, Tohtz S, Putzier M, Kox WJ (2004) Postoperative epidural anesthesia preserves lymphocyte, but not monocyte, immune function after major spine surgery. Anesth Analg 98(4) 1086-1092... 

Discuss the mechanisms by which spinal anesthesia and epidural anesthesia exert their effects... 

Epidural anesthesia is administered by injecting local anesthetic into the epidural space. Located outside the spinal cord on its dorsal surface, the epidural space contains fat and is highly vascular. Therefore, this form of anesthesia can be performed safely at any level of the spinal cord. Furthermore, a catheter may be placed into the epidural space, allowing for continuous infusions or repeated bolus administrations of anesthetic. 

The primary site of action of epidurally administered agents is on the spinal nerve roots. As with spinal anesthesia, the choice of drug to be used is determined primarily by the duration of anesthesia desired. However, when a catheter has been placed, short-acting drugs can be administered repeatedly. Bupivacaine is typically used when a long duration of surgical block is needed. Lidocaine is used most often for intermediate length procedures chloroprocaine is used when only a very short duration of anesthesia is required. 

An important difference between epidural anesthesia and spinal anesthesia is that agents injected into the epidural space may readily enter the blood due to the presence of a rich venous plexus... 

Epidural administration in cesarean section. cDental anesthesia. 

G. Duarte, and S.P. da Cunha. Pharmacokinetics and transplacental distribution of fentanyl in epidural anesthesia for normal pregnant women. Eur I Clin Pharmacol. 61 517-522 (2005). 

Epidural anesthesia This term is understood to be an introduction of local anesthetic into the spinal cord membrane of the intervertebral space. It is used during obstetrical and gynecological interventions that do not require a fast development of anesthesia. Drugs such as lidocaine, mepivacaine, bupivacaine, ethidocaine, and chloroprocaine are used for this purpose. 

Chloroprocaine is used in situations requiring fast-acting pain relief. It is also used in infiltration anesthesia, blocking peripheral nerve transmission, and in spinal and epidural anesthesia. Nesacaine is a synonym for chloroprocaine. 

Lidocaine is the most widely used local anesthetic. Its excellent therapeutic activity is fast-acting and lasts sufficiently long to make it suitable for practically any clinical use. It stabilizes cell membranes, blocks sodium channels, facilitates the secretion of potassium ions out of the cell, and speeds up the repolarization process in the cell membrane. It is used for terminal infiltration, block, epidural, and spinal anesthesia during operational interventions in dentistry, otolaryngology, obstetrics, and gynecology. It is also used for premature ventricular extrasystole and tachycardia, especially in the acute phase of cardiac infarction. Synonyms for this drug are xylocaine, neflurane, and many others. 

Neuraxial anesthesia and postoperative indwelling epidural catheter use Spinal or epidural hematomas, which may result in long-term or permanent paralysis, can occur with the use of anticoagulants and neuraxial (spinal/epidural) anesthesia or spinal puncture. The risk of these events may be higher with postoperative use of indwelling epidural catheters or concomitant use of other drugs affecting hemostasis, such as NSAIDs. 

Amide-type agents include articaine, lidocaine, bupivacaine, prilocaine, mepivacain and ropiva-caine. These are metabolized in the liver by microsomal enzymes with amidase activity. The amide group is preferred for parenteral and local use. If by accident rapidly administered intravascularly these agents, especially bupivacaine but also lidocaine, can produce serious and potentially lethal adverse effects including convulsions and cardiac arrest. They can more easily accumulate after multiple administrations. Intravenous lidocaine is sometimes used for regional anesthesia, for infiltration procedures, for the induction of nerve blockade and for epidural anesthesia. However, it is also used as an antiarrhythmic. Bupivacaine is a long-acting local anesthetic used for peripheral nerve blocks and epidural anesthesia. 

The first clinical uses of a local anesthetic agent occurred in 1884, when cocaine was employed as a topical agent for eye surgery and to produce a nerve block. These events inaugurated a new era, that of regional anesthesia. New applications were developed, including spinal, epidural, and caudal anesthesia. The search for a better local anesthetic led to chemical synthesis of a number of other compounds that have more selective local anesthetic properties and few systemic side effects. 

Regional block, a form of anesthesia that includes spinal and epidural anesthesia, involves injection near a nerve or nerve plexus proximal to the surgical site. It provides excellent anesthesia for a variety of procedures. Brachial plexus block is commonly used for the upper extremity. Individual blocks of the sciatic, femoral, and obturator nerves can be used for the lower extremity. An amount that is close to the maximally tolerated dose is required to produce blockade of a major extremity. 

Lumbar epidural anesthesia affects the same area of the body as does spinal anesthesia. As the name implies, the... 

Epidural anesthesia is especially useful in obstetrics. Excellent analgesia occurs and the patient remains awake. Analgesia by the epidural route can be provided for labor and delivery or for cesarean section. Bupivacaine in lower concentrations has the advantage of providing excellent analgesia while minimally reducing motor strength. 

In the caudal form of extradural anesthesia, the agent is introduced through the sacral hiatus above the coccyx. It is particularly applicable to perineal and rectal procedures. Anesthetization of higher anatomical levels is not easily obtained, because the required injection volume can be excessive. Although caudal anesthesia has been used extensively in obstetrics, lumbar epidural blockade is now more commonly used because of the lower dose of drug required in addition, the sacral segments are spared until their anesthesia is required for the delivery. 

Increased risk of spinal/epidural hematomas with neuraxial anesthesia or spinal puncture. Risk is further increased by use of indwelling spinal catheters, repeated/ traumatic epidural/spinal puncture, or use of drugs affecting hemostasis (NSAIDs, anticoagulants, platelet inhibitors). 

Epidural anesthesia—injection of local anesthetic into the space external to the dural sac that encloses the spinal cord, enabling nerves to the pelvis to be selectively anesthetized during obstetrical labor and delivery... 

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