Topical anesthesia

Anesthesia Topical Apply aerosol, gel, ointment, liquid q4-12h as needed. 

Peripheral or sympathetic nerve block (regional anesthesia) Topical Up to 200 ml of a... 

Topical anesthesia Topical Applyto the affected areas as needed. Maximum dosage 28g/24 hr. 

Topical anesthesia of nose and throat, abolish laryngeal and esophageal reflexes prior to diagnostic procedure Topical Direct application of a 0.25% or 0.5% topical solution or by oral inhalation of a nebulized 0.5% solution. Total dose should not exceed 20 mg. Mild pain, burning and/or pruritus associated with herpes labialis (cold sores or fever blisters) Topical Apply to the affected area no more than 3-4 times a day. Ophthalmic anesthesia Topical 1-2 drops of a 0.5% solution. 

Lidocaine hydrochloride [73-78-9] (Xylocaine), is the most versatile local anesthetic agent because of its moderate potency and duration of action, rapid onset, topical activity, and low toxicity. Its main indications are for infiltration, peripheral nerve blocks, extradural anesthesia, and in spinal anesthesia where a duration of 30 to 60 min is desirable. Because of its vasodilator activity, addition of the vasoconstrictor, epinephrine, increases the duration of action of Hdocaine markedly. It is also available in ointment or aerosol preparations for a variety of topical appHcations. 

Mepivacaine hydrochloride [1722-62-9] similar in profile to Hdocaine, is used for infiltration, peripheral nerve blocks, and extradural anesthesia. It appears to be less toxic than Hdocaine in adults but more toxic in newborns. The duration of action is longer than that of Hdocaine because of its lower vasodilator activity. Mepivacaine has Htde topical activity. 

Topical anesfliesia involves die application of die anes-flietic to die surface of the skin, open area, or mucous membrane The anesthetic may be applied wifli a cotton swab or sprayed on the area This type of anesthesia may be used to desensitize the skin or mucous membrane to the injection of a deeper local anesthetic. In some instances, topical anesthetics may be applied by the nurse ... 

Gentian violet solution is used to delineate the areas to be treated. Refrigerant topical anesthesia is used to freeze the skin prior to the procedure. Holding the skin taut, the dermabrader treats one anatomic unit at a time. Post-operatively, patients may have an open or closed dressing system, use antiviral agents, antibacterials and corticosteroids. The re-epithelialization is complete in 5-7 days and residual erythema is common for up to 4 weeks. 

The use of cocaine for local anesthesia has been largely replaced by synthetic drugs that produce less psychoactive effects. However, cocaine is still used sometimes for topical anesthesia of the upper respiratory tract. 

Topical anesthesia Local use of drugs of this kind on the mucous membranes of the nose, mouth, larynx, tracheobrachial tree, eyes, urinary tract, and gastrointestinal tract causes superficial anesthesia. 

Benzocaine is used in topical anesthesia on the skin and mucous membranes in the form of aerosols, or as creams for reduction of pain caused by itching, cuts, bites, etc. It begins to work 15-30 sec after application and lasts 12-15 min. It is also used under the names anestezin, dermoplast, and others. 

Cyclomethycaine is also used in topical anesthesia on the skin or mucons membranes for cuts, bites, and also for urological examinations. A common synonym of this drug is surfacaine. 

Topical anesthesia will increase the bioavailability of ophthalmic agents by decreasing the blink reflex and the production and turnover of tears. 

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. 

The vasoconstrictor actions of epinephrine and norepinephrine have been used to prolong the action of local anesthetics by reducing local blood flow in the region of the injection. Epinephrine has been used as a topical hemostatic agent for the control of local hemorrhage. Norepinephrine is infused intravenously to combat systemic hypotension during spinal anesthesia or other hypotensive conditions in which peripheral resistance is low, but it is not used to combat the hypotension due to most types of shock. In shock, marked sympathetic activity is already present, and perfusion of organs, such as the kidneys, may be jeopardized by norepinephrine administration. 

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. 

Local anesthetics are used extensively on the mucous membranes in the nose, mouth, tracheobronchial tree, and urethra. The vasoconstriction produced by some local anesthetics, cocaine especially, adds a very important advantage to their use in the nose by preventing bleeding and inducing tissue shrinkage. Topical anesthesia permits many diagnostic procedures in the awake patient, and when it is combined with infiltration techniques, excellent anesthesia may be obtained for many... 

Cocaine hydrochloride remains useful primarily because of the vasoconstriction it provides with topical use. Toxicity prohibits its use for other than topical anesthesia. 

Procaine hydrochloride Novocain) is readily hydrolyzed by plasma cholinesterase, although hepatic metabolism also occurs. It is not effective topically but is employed for infiltration, nerve block, and spinal anesthesia. It has a relatively slow onset and short (1 hour) duration of action. All concentrations can be combined with epinephrine. It is available in dental cartridges with phenylephrine as the vasoconstrictor. 

Lidocaine hydrochloride Xylocaine) is the most commonly used local anesthetic. It is well tolerated, and in addition to its use in infiltration and regional nerve blocks, it is commonly used for spinal and topical anesthesia and as an antiarrhythmic agent (see Chapter 16). Lidocaine has a more rapidly occurring, more intense, and more prolonged duration of action than does procaine. 

EMLA cream (lidocaine 2.5% and prilocaine 2.5%) consists of a eutectic mixture of focal anesthetics. It is used to provide topical anesthetic to intact skin. Other topical preparations are effective only on mucosal surfaces. EMLA has been shown to reduce pain on venipuncture and provide substantial anesthesia for skin graft donor sites. No significant local or systemic toxicity has been demonstrated. 

Application to the nerve cell ending would result only in topical anesthesia, and blockade of the neuromuscular junction could produce respiratory failure. Administration to the spinal cord is too general an answer. The injection must be near a nerve or nerve plexus proximal to the surgical site. 

Local skin disorders (minor Burns, insect Bites, prickly heat, skin manifestations ofchick-enpox, aBrasions), and mucous memBrane disorders (local anesthesia of oral, nasal, and laryngeal mucous memBranes local anesthesia of respiratory, urinary tract relief of discomfort of pruritus ani, hemorrhoids, pruritus vulvae) Topical Apply to affected areas as needed. 

Infiltration anesthesia, dental anesthesia, control of severe pain (post herpatic neuralgia, cancer pain, or hums) Topical A single dose of 350-600 mg using a 0,25 or 0,5% solution, Use 0,9% sodium chloride for dilution. 

Previously used as component of "Magic Numbing Solution" or TAC Sol (epinephrine 1 2,000, tetracaine 0.5%, cocaine 11.8%) and LET Sol (lidocaine 4%, epinephrine 0.1%, tetracaine 0.5%), which are used as topical anesthesia for repair of minor lacerations. Topical tetracain solutions no longer available... 

Topical anesthesia—direct application to the skin, or a mucous membrane, of the local anesthetic in the form of a spray, cream, or gel... 

Route of administration Fomivirsen is administered intravitreally with topical and/or local anesthesia. 

Local anesthetic action, also known as "membrane-stabilizing" action, is a prominent effect of several 3 blockers (Table 10-2). This action is the result of typical local anesthetic blockade of sodium channels (see Chapter 26) and can be demonstrated experimentally in isolated neurons, heart muscle, and skeletal muscle membrane. However, it is unlikely that this effect is important after systemic administration of these drugs, since the concentration in plasma usually achieved by these routes is too low for the anesthetic effects to be evident. These membrane-stabilizing 3 blockers are not used topically on the eye, where local anesthesia of the cornea would be highly undesirable. Sotalol is a nonselective 3-receptor antagonist that lacks local anesthetic action but has marked class III antiarrhythmic effects, reflecting potassium channel blockade (see Chapter 14). 

Topical local anesthesia is often used for eye, ear, nose, and throat procedures. Satisfactory topical local anesthesia requires an agent capable of rapid penetration across the skin or mucosa, and with limited tendency to diffuse away from the site of application. Cocaine, because of its excellent penetration and local vasoconstrictor effects, has been used extensively for ear, nose and throat (ENT) procedures. Cocaine is somewhat irritating and is therefore less popular for ophthalmic procedures. Recent concern about its potential cardiotoxicity when combined with epinephrine has led most otolaryngology surgeons to switch to a combination containing lidocaine and epinephrine. Other drugs used for topical anesthesia include lidocaine-bupivacaine combinations, tetracaine, pramoxine, dibucaine, benzocaine, and dyclonine. 

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