This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Anesthesia, Subject name: Pharmacology
Anaesthesia contraindicated In volvulus of gut is 
Select and explain. 
A. Halothane, B. Nitrous oxide, C. Ketamine, D. Pancuronium
B: Nitrous oxide
Answer: B: Nitrous oxide 
Explanation: Nitrous oxide displaces nitrogen in air filled cavities and while doing so it enters the cavities faster that is even before nitrogen escapes. This results in expansion of such cavities leading to pnemothorax and air embolus.Hence nitrous oxide should be avoided in such patients. From padmaja 4th edition Page no 191