Lignocaine is used in –
**Core Concept**
Lignocaine, also known as lidocaine, is a local anesthetic and antiarrhythmic medication that works by blocking sodium channels in nerve cells, preventing the initiation and transmission of nerve impulses. Its pharmacological properties make it useful in various clinical applications.
**Why the Correct Answer is Right**
Lignocaine is used to provide local anesthesia for minor surgical procedures, dental procedures, and for pain relief during medical procedures. It is also used to treat certain types of irregular heartbeats, such as ventricular tachycardia and ventricular fibrillation, by stabilizing the cardiac membrane potential. The mechanism of action involves the inhibition of sodium channels, which reduces the frequency of action potentials in the heart.
**Why Each Wrong Option is Incorrect**
**Option A:** Lignocaine is not primarily used as a muscle relaxant, although it may have some minor effects on muscle tone.
**Option B:** Fentanyl is a potent opioid analgesic, not a local anesthetic or antiarrhythmic medication like lignocaine.
**Option C:** Propofol is a sedative-hypnotic agent used for inducing and maintaining anesthesia, but it is not a local anesthetic or antiarrhythmic medication.
**Clinical Pearl / High-Yield Fact**
Lignocaine can cause systemic toxicity if used in high doses or with rapid injection, leading to symptoms such as seizures, tremors, and cardiac arrhythmias.
**Correct Answer:** D. Local anesthesia and antiarrhythmic medication.