Lignocaine Flashcards
Action of Lignocaine is affected by??
- pH at the site of action (obv)
- Vasoconstrictor in the LA
- Blood flow at the site of action
But not… By — action of cholinesterase at the site of injection
Systemic effects that occur as a result result of systemic absorption of Lignocaine?
- Tonic-clonic convulsions
- Decreased CO (Means CVS collapse or myocardial depression) n Cardiac arrythmias…
- Depression of Respi syst
But NOT…. Increased gastric motility ..
ECG changes can be first observed when level of ligno is more than?
5-6 ug/ml
Cerebral blood level of LIGNO required to induce seizure activity?
7.5 ug/ml
Ligno is used most commonly in dentistry because?
Causes lesser incidence of ALLERGY….
What’s in eutectic mixture of LA?
Ligno + Prilo
Onset of action of Ligno?
3 to 5 min
Max recomme dose of LIGNO with Epi?
7 mg per kg body wt
Xylocaine strength used in dentistry?
2%
The first non-ester compound used as LA in dentistry?
Ligno
Most commonly used LA ?
1:80,000 Xylocaine hcl
Max conc of ligno used as topical?
4%
Amide type of LA undergo biotransformation in?
Liver …. by microsomal enz….
Ester type LA r inactivated in n by??
In plasma .. n us catalyzed by Plasma cholinesterase….
Therefore…. ESTER LA r contraindicated in Cholinesterase defi…
Max dose of LA without Adr?
4.4 mg/kg body wt… N not to exceed 300 mg
Max dose of LA with Adr?
7 mg/kg… N NOT to exceed 500 mg…
LA used as surface anesthetic on delicate mucous memb such as anal canal n SPINAL ANESTHESIA?
Dibucaine
Properties of MYELINATED Nerve fibres?
- Conduction is faster here than in non-myelinated…
- Outer layer is of lipid
- Depolarization occurs at the nodes of Ranvier.. as LA doesn’t penetrate the myelin sheath….
LA r acidic salts of weak bases or basic salts of weak acids?
ACIDIC salts of weak bases..
Sensitivity to LA is greatest in what type of fibres?
C fibres…
Position for syncope (PT who had fainted)??
Trendelburg position (Semireclined)
