This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Anaesthesia
[{'content': 'About lignocaine, all are true except ? \nSelect and explain. \nA. It is ester group of local anaesthetic, B. It has antiarrhythmic propey, C. Can penetrate through mucous membrane, D. It can precipitate malignant hypehermia', 'role': 'user'}, {'content': "Answer: A \nExplanation: Ans. is 'a' i.e., It is ester group of local anaesthetic Lidocaine It is the most commonly used local anaesthetic. It also has antiarrhythmic propey. Systemic toxicity is less than bupivacaine. CNS involvement occurs at much lesser dose than CVS involvement. It can precipitate malignant hypehermia --> should not be used in these patients. For regional anaesthesia, it is used in different concentraions for different type of anaesthesia Surface (topical) analgesia : 4%, nerve block : 1 - 2%, Spinal anaesthesia : 5%, Epidural : 1 - 2 %, Beir's block (intravenous regional anaesthesia) : 0.5% and infiltration block : 1 - 2%. Maximum safe dose of lidocaine wihout adrenaline is 300 mg (4.5 mg/kg) and with adrenaline is 500 mg (7 mg/kg). Besides local anaesthesia lidocaine is used : - To treat ventricular arrhythmias. To blunt the cardiovascular response to laryngoscopy and intubation, (i.v. or intrathecal administered lidocaine).", 'role': 'assistant'}]