Lignocaine

Question 1

Action of Lignocaine is affected by??

Answer 1

1. pH at the site of action (obv)
2. Vasoconstrictor in the LA
3. Blood flow at the site of action

But not… By — action of cholinesterase at the site of injection

Question 2

Systemic effects that occur as a result result of systemic absorption of Lignocaine?

Answer 2

1. Tonic-clonic convulsions
2. Decreased CO (Means CVS collapse or myocardial depression) n Cardiac arrythmias…
3. Depression of Respi syst

But NOT…. Increased gastric motility ..

Question 3

ECG changes can be first observed when level of ligno is more than?

Answer 3

5-6 ug/ml

Question 4

Cerebral blood level of LIGNO required to induce seizure activity?

Answer 4

7.5 ug/ml

Question 5

Ligno is used most commonly in dentistry because?

Answer 5

Causes lesser incidence of ALLERGY….

Question 6

What’s in eutectic mixture of LA?

Answer 6

Ligno + Prilo

Question 7

Onset of action of Ligno?

Answer 7

3 to 5 min

Question 8

Max recomme dose of LIGNO with Epi?

Answer 8

7 mg per kg body wt

Question 9

Xylocaine strength used in dentistry?

Answer 9

2%

Question 10

The first non-ester compound used as LA in dentistry?

Answer 10

Ligno

Question 11

Most commonly used LA ?

Answer 11

1:80,000 Xylocaine hcl

Question 12

Max conc of ligno used as topical?

Answer 12

4%

Question 13

Amide type of LA undergo biotransformation in?

Answer 13

Liver …. by microsomal enz….

Question 14

Ester type LA r inactivated in n by??

Answer 14

In plasma .. n us catalyzed by Plasma cholinesterase….

Therefore…. ESTER LA r contraindicated in Cholinesterase defi…

Question 15

Max dose of LA without Adr?

Answer 15

4.4 mg/kg body wt… N not to exceed 300 mg

Question 16

Max dose of LA with Adr?

Answer 16

7 mg/kg… N NOT to exceed 500 mg…

Question 17

LA used as surface anesthetic on delicate mucous memb such as anal canal n SPINAL ANESTHESIA?

Answer 17

Dibucaine

Question 18

Properties of MYELINATED Nerve fibres?

Answer 18

1. Conduction is faster here than in non-myelinated…
2. Outer layer is of lipid
3. Depolarization occurs at the nodes of Ranvier.. as LA doesn’t penetrate the myelin sheath….

Question 19

LA r acidic salts of weak bases or basic salts of weak acids?

Answer 19

ACIDIC salts of weak bases..

Question 20

Sensitivity to LA is greatest in what type of fibres?

Answer 20

C fibres…

Question 21

Position for syncope (PT who had fainted)??

Answer 21

Trendelburg position (Semireclined)