LIDOCAINE HYDROCHLORIDE- lidocaine hydrochloride spray
Pediatric LTA ® Kit
LTA ® 360 Kit
LTA ® II Kit
STERILE DISPOSABLE KIT
WITH LIDOCAINE HYDROCHLORIDE
TOPICAL SOLUTION, USP FOR
The LTA Kits are sterile disposable kits for producing rapid, effective topical anesthesia of the interior of the larynx and trachea. Each kit contains (1) a sterile, anatomically-curved plastic cannula with attached vial injector, and (2) a single-use vial prefilled with 4 mL of a 4% sterile aqueous solution of Lidocaine Hydrochloride Topical Solution, USP for adults or 5 mL of a 2% sterile aqueous solution for children.
The LTA 360 Kit is preattached and distributes anesthetic in a circumferential spray pattern. The LTA II Kit and the Pediatric LTA Kit are not preattached and distribute anesthetic in a longitudinal spray pattern. Contents of each kit are sterile in intact unit package. The kit is designed for one-time use only. After use, it should be discarded without disassembly.
The kit is used to instill a jet spray of lidocaine hydrochloride solution into the interior of the larynx and trachea for local anesthesia in the unconscious patient just prior to endotracheal intubation. This form of application also is effective as a final stage of topical anesthesia in the conscious patient (after initial use of an atomizer spray or other appropriate technique for applying topical anesthetic to the pharynx and epiglottis) prior to laryngeal or tracheobronchial endoscopic procedures.
Lidocaine Hydrochloride Topical Solution, USP is a local anesthetic agent and is administered topically. See INDICATIONS AND USAGE for specific uses. It is supplied in 5 mL graduated disposable glass vials containing 4 mL of 4% (160 mg) or 5 mL of 2% (100 mg) sterile, topical solution of lidocaine hydrochloride. Each mL contains:
|40 mg||20 mg|
May contain sodium hydroxide and/or hydrochloric acid for pH adjustment. pH 6.5 (5.0 to 7.0). No preservative is added since all or part of the contents of the syringe unit is administered as a single dose and the unit should not be reused.
Lidocaine hydrochloride is designated chemically as 2-(diethylamino)-2΄,6΄-acetoxylidide monohydrochloride. It has the following structural formula:
Mechanism of action: Lidocaine stabilizes the neuronal membrane by inhibiting the ionic fluxes required for the initiation and conduction of impulses, thereby effecting local anesthetic action.
Onset and Duration of Anesthesia: The onset of action is rapid.
Hemodynamics: Excessive blood levels may cause changes in cardiac output, total peripheral resistance, and mean arterial pressure. These changes may be attributable to a direct depressant effect of the local anesthetic agent on various components of the cardiovascular system. The net effect is normally a modest hypotension when the recommended dosages are not exceeded.
Pharmacokinetics and Metabolism: Information derived from other formulations, concentrations and usages reveals that lidocaine is completely absorbed following parenteral administration, its rate of absorption depending, for example, upon such factors such as the site of administration and the presence or absence of a vasoconstrictor agent. Lidocaine may be absorbed following topical administration to mucous membranes, its rate and extent of absorption depending upon concentration and total dose administered, the specific site of application and duration of exposure. In general, the rate of absorption of local anesthetic agents following topical application occurs most rapidly after intratracheal administration. Lidocaine is also well absorbed from the gastrointestinal tract, but little intact drug appears in the circulation because of biotransformation by the liver.
Lidocaine is metabolized rapidly by the liver, and metabolites and unchanged drug are excreted by the kidneys. Biotransformation includes oxidative N-dealkylation, ring hydroxylation, cleavage of the amide linkage, and conjugation. N-dealkylation, a major pathway of biotransformation, yields the metabolites monoethylglycinexylidide and glycinexylidide. The pharmacological/ toxicological actions of these metabolites are similar to, but less potent than, those of lidocaine. Approximately 90% of lidocaine administered is excreted in the form of various metabolites, and less than 10% is excreted unchanged. The primary metabolite in urine is a conjugate of 4-hydroxy-2,6-dimethylaniline.
Studies have shown that peak blood levels of lidocaine may occur as early as 5 and as late as 30 minutes after endotracheal administration of a 4% lidocaine HCl solution.
The plasma binding of lidocaine is dependent on drug concentration, and the fraction bound decreases with increasing concentration. At concentrations of 1 to 4 μg of free base per mL, 60 to 80 percent of lidocaine is protein bound. Binding is also dependent on the plasma concentration of the alpha-1-acid glycoprotein.
Lidocaine crosses the blood-brain and placental barriers, presumably by passive diffusion.
Studies of lidocaine metabolism following intravenous bolus injections have shown that the elimination half-life of this agent is typically 1.5 to 2.0 hours. Because of the rapid rate at which lidocaine is metabolized, any condition that affects liver function may alter lidocaine kinetics. The half-life may be prolonged two-fold or more in patients with liver dysfunction. Renal dysfunction does not affect lidocaine kinetics but may increase the accumulation of metabolites.
Factors such as acidosis and the use of CNS stimulants and depressants affect the CNS levels of lidocaine required to produce overt systemic effects. Objective adverse manifestations become increasingly apparent with increasing venous plasma levels above 6.0 μg free base per mL. In the rhesus monkey arterial blood levels of 18-21 μg/mL have been shown to be threshold for convulsive activity.
Lidocaine Hydrochloride Topical Solution is indicated for the production of topical anesthesia of the mucous membranes of the respiratory tract.
Lidocaine is contraindicated in patients with a known history of hypersensitivity to local anesthetics of the amide type.
LIDOCAINE HYDROCHLORIDE TOPICAL SOLUTION SHOULD BE EMPLOYED ONLY BY CLINICIANS WHO ARE WELL VERSED IN DIAGNOSIS AND MANAGEMENT OF DOSE-RELATED TOXICITY AND OTHER ACUTE EMERGENCIES THAT MIGHT ARISE AND THEN ONLY AFTER ENSURING THE IMMEDIATE AVAILABILITY OF OXYGEN, OTHER RESUSCITATIVE DRUGS, CARDIOPULMONARY EQUIPMENT, AND THE PERSONNEL NEEDED FOR PROPER MANAGEMENT OF TOXIC REACTIONS AND RELATED EMERGENCIES (See also ADVERSE REACTIONS and PRECAUTIONS.) DELAY IN PROPER MANAGEMENT OF DOSE-RELATED TOXICITY, UNDERVENTILATION FROM ANY CAUSE AND/OR ALTERED SENSITIVITY MAY LEAD TO THE DEVELOPMENT OF ACIDOSIS, CARDIAC ARREST AND, POSSIBLY DEATH.
Lidocaine Hydrochloride Topical Solution should be used with extreme caution if there is sepsis or severely traumatized mucosa in the area of application, since under such conditions there is the potential for rapid systemic absorption.