- It is most widely used LA
- It is amino amide linked of local anesthetics [Other amino amide linked LAs are: Bupivacaine, Dibucaine, Etidocaine, Levobupivacaine, Prilocaine, Ropivacaine]
- It blocks nerve conduction within 3 minutes after injection.
- Lignocaine is rapid acting local anesthetics used in medical practice.
- Nerve block is intermediate duration of efficacy approximately 60-120 minutes.
- Adrenaline also used with lignocaine, which is vasocontrictor of arteries that delays the resorption of lignocaine resulting in increase duration of anesthesia almost two folds.
- It is used for surface application for itching, burning and pain from superficial surfaces.
- It is also used in nerve block, infiltration, epidural, spinal, dental anesthetics and intravenous regional block.
- Most side effects are drowsiness, altered taste, tinnitus, mental clouding.
- It is also used as antiarrhythmic drugs Class IB [ Na+ Channels blockers ( Membrane stabilizing agents)]. It is used intravenously for the treatment of ventricular arrhythmias.
- Concentration used in general practice is usually 0.5% to 2%
Mechanism of action:
- Lignocaine blocks nerve conduction by blocking the Fast Voltage gated Na+ channels in the neuronal cell membrane.
- Sufficient blocks of neuronal cell membrane results in no depolarization of membrane of postsynaptic neuron and fails to transmit action potential.
Contraindications:
- Hypersensitivity reaction to lignocaine
- Heart block ( 2nd or 3rd degree )
- Severe SA block
- Combination with other antiarrhythics drugs: Class I antiarrhythmics drugs [ IA: (Qunidine, Disopyramide, Procainamide), IC: ( Flecainide, Propafenone ) and Class III ( Amiodarone Hcl )
- Hypotension
- Bradycardia
- Pacemaker
Adverse effects of lignocaine:
1, CNS effects: Occurs in lower doses
- Convulsions
- Nervousness
- Tingling, tinnitus, tremore
- Dizziness, Depression, Drowsiness
- Blurred vision
- Muscle twitching
- Respiratory depression and arrest or apnea
- Loss of consciousness or Coma or Seizures
2, CVS effects: Occurs in higher doses
- Cardiac arrhythmias
- Hypotension
- Bradycardia
- Cardiac arrest
- Lognocaine is metabolized in liver by CYP3A4, approximately 95% of metabolites
- Elimination half life is almostly 90-120 minutes.
- Elimination is prolonged in case of hepatic impairment ( 340 min. ) and congestive heart failure ( 135 minutes )
More related topics and videos:
Digital ring block video
Ulnar nerve block video
Epidural anesthesia video
Spinal anesthesia video
Median nerve block video
Radial nerve block video
Ulnar nerve block ( USG guided )
Axillary nerve block ( USG guided )
Forearm nerve block ( USG guided )
More related topics and videos:
Digital ring block video
Ulnar nerve block video
Epidural anesthesia video
Spinal anesthesia video
Median nerve block video
Radial nerve block video
Ulnar nerve block ( USG guided )
Axillary nerve block ( USG guided )
Forearm nerve block ( USG guided )