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
Dibucain number refers to ? 
Select and explain. 
A. Ach cholinestrase activity derangement, B. Potency of muscle relaxants, C. Potency of general anaesthetics, D. None
A: Ach cholinestrase activity derangement
Answer: A: Ach cholinestrase activity derangement 
Explanation: Ans. is 'a' i.e., Ach chlinestrase activity derangement Dibucain number : Dibucain (a local anaesthetic) inhibits 80% of normal pseudocholinesterase and 20% of atypical (non-functional) pseudocholinesterase. Therefore normal dibucain number is 70-80%. Dibucain number is used to measure the activity of atypical pseudocholinesterase.