This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Anesthesia Machine, Subject name: Anaesthesia
Dose of local anesthetics for peripheral nerve block is decreased in patients with hypovolemia shock because- 
Select and explain. 
A. Preferential perfusion of vital organs in shock predisposes more to local anesthetics toxicity, B. Drugs cannot be metabolized, C. Sensitivity of voltage gated channel increases in shock, D. Drug is not systemically absorbed to less require
A: Preferential perfusion of vital organs in shock predisposes more to local anesthetics toxicity
Answer: A: Preferential perfusion of vital organs in shock predisposes more to local anesthetics toxicity 
Explanation: In hypovolemia shock there is preferential perfusion of vital organs so whatever drug is intravascularly absorbed goes to vital organs CNS and CVS end cause systemic toxicity. Decreasing systemic absorption of local anesthetics increase their safety margin in clinical uses. The rate and extent of systemic absorption depends on the site of injection, the dose, the drugs intrinsic Pharmacokinetic propeies and the addition and cytochrome P450 enzymes. Severe liver disease may slow the clearance of amino amide local anesthetics and significant drug levels may therefore accumulate.