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': 'A 70 kg old athlete was posted for surgery, Patient was administered succinylcholine due to unavailability of vecuronium. It was administered in intermittent dosing (total 640 mg). During recovery, the patient was not able to respire spontaneously & move limbs. What is the explanation – \nSelect and explain. \nA. Pseudocholinesterase deficiency increasing action of syccinylcholine, B. Phase 2 blockade produced by succinylcholine, C. Undiagnosed muscular dystrophy and muscular weakness, D. Muscular weakness due to fasciculation produced by succinylcholine', 'role': 'user'}, {'content': 'Answer: B \nExplanation: This a case of phase II block, caused by a high dose of succinylcholine.\n\n"After administration of 7-10 mg/kg or 30-60 minutes of exposure to succinylcholine, non-deplarizing dual or\xa0phase II block occurs".\n— Millers\n\nOption a requires specific mention here because prolonged paralysis with succinylcholine administration may also occur in pseudocholinesterase deficiency. But, this is due to the phase II block.\nSo, Sch can cause phase II block in two conditions:-\n\n\nWhen Sch is administered in high doses\nPatients with atypical or deficient pseudocholinesterase.\xa0It these patients it occurs at\xa0usual doses\xa0as usual amount of Sch is not metabolized.', 'role': 'assistant'}]