What is mechanism of action of curonium drugs as muscle relaxant?: (A) Persistently depolarizing at neuromuscular junction, (B) Act competitively on Ach receptors blocking postsynaptically, (C) Repetitive stimulation of Ach receptors on muscle end plate, (D) Inhibiting the calcium channels on presynaptic membrane
Answer is B. Persistently depolarizing at neuromuscular junction - propey of succinylcholine depolarising eg : succinylcholine 1. MOA - persistent / prolonged depolarising of nicotinic cholinergic receptors 2. fasiculation seen 3. post operative myalgia 4. not reversed by neostigmine 5. train of four response not seen 6. TOF ratio (B/A = 1 ) 7. neuromuscular monitoring not done 8. no post tetanic facilitation non - depolarising 1. MOA - competitive antagonist 2. fasiculation not seen 3. no post operative myalgia 4. reversed by neostigmine 5. train of four response seen 6. TOF ratio (B/A< 1 ) 7. neuromuscular monitoring done 8. post tetanic facilitation seen