LIDOCAINE::THE GOLD STANDARD DRUG

PRESENTED BY-VANDITA SINGH

LidocaineLidocaine, the first amino amide-type local anesthetic,

was first synthesized under the name Xylocaine by Swedish chemist Nils Löfgren in 1943.

FDA Approved-November 1948

IndicationsRapid acting local anesthetic for procedures

ranging from infiltration to regional nerve block Antiarrhythmic in the treatment of vent.

arrhythmias Treatment of status epilepticus (INVESTIGATIONAL)

Treatment of pain OperativeNeuropathic pain

PharmacologyHalf life: 1.6 hrs(~90 min)Distribution: Lipo-philic, widely distributed into

bodypH of plain solution-6.5pH of vasoconstrictor containing solution-5.0-5.5Onset of action –rapidPregnancy clissification-BEffective dental concentration-2%Protein binding: 60-80 %

MAXIMUM RECOMMENDED DOSE

The max. manufactures recommended dose of lidocaine with epinephrine is 7.0mg/kg body weight for adult patient,not to exeed dose of 500mg.

4.4mg/kg body weight dose of lidocaine without a vasoconstrictor

ACTIONS

ON CNS

(i) Blocks conduction around a nerve

Anaesthesia(ii) Initially causes drowsiness & lethargy(iii) Higher doses cause excitation followed by depression

ON CVS

Heart Blood vessels

Abbreviates Vasodilatation in Effective the injected area Refractory Period

MECHANISM OF ACTION

Alters depolarization inneurons by blocking the fastvoltage gated sodium (Na+)channels in the cellmembrane. With sufficientblockade, the membrane ofthe presynaptic neuron willnot depolarize and so fail totransmit an action potential,leading to its anaestheticeffects

PHARMACOKINETICS

Absorption:Absorbed rapidly after parenteral administration & from GIT & Respiratory Tract

Metabolism: Metabolized in the liver Excretion: Metabolites and

unchanged drug are excreted by the kidneys in the urine

ROUTES OF ADMINISTRATION

Intravenous injection (sometimes combined with epinephrine)

Dermal patch (sometimes combined with prilocaine)

Nasal instillation/spray (combined with phenylephrine)

Topical gel

Its vasodilating effect limits

pulpal anesthesia to

only 5-10min.

This leads to higher blood

levels& increased

risk of adverse reaction

The inclusion of

epinephrine produces a decrease in blood flow leading to

decrease in bleeding at the site of injection.Increased duration-~60min of

pulpal anesthesia

Decreases blood flow .Increases

duration of action~60min of pulpal anesthesia.

2% WITHOUT VASOCONSTRICTOR(LIDOCAIN PLAIN)

2% WITH EPINEPHRINE1:50,000

2% WITHEPINEPHRINE1:100,000

The duration &depth obtained with both lidocaine-epinephrine solution are equivalent although not the same level of hemostasis.{2%lidocaine with 1:50,000

epinephrine is recommended because it decrease bleeding by 50% as compared with 1:100,000

epinephrene dilution}

DIFFERENT FORMS OF LIDOCAINE

Intravenous Lidocaine for AmbulatoryAnesthesia

Christopher L. Wu, MD ,Inter Anes Research Society,Dec. 2009

Using 1.5–3 mg kg\ hlidocaine significantly reduced the incidence of nausea and vomiting (32% vs 52%), Marginally reduced pain scores .

ADVERSE EFFECTS

OVERDOSE

CONTRAINDICATIONS

EUTECTIC MIXTURE OF LOCAL ANESTHETICS (EMLA)- LIDOCAINE &

PRILOCAINEEutectic mixture refers to

lowering of melting point of two solids when they are mixed

Lidocaine+Prilocaine at 25oC

Oil emulsified into water to form a cream

CLINICAL USES/ INDICATIONS

Dermal anaesthesia, specifically applied to prevent pain associated with intravenous catheter insertion, blood sampling, superficial surgical procedures on intact skin & mucous membranes

Topical anaesthesia for cleansing or debridement of ulcers, to numb the skin before tattooing as well as laser hair removal