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
[{'content': 'Which anesthestic modality is to be avoided in sickle cell disease \nSelect and explain. \nA. General anesthesia, B. Branchial plexus block, C. Intravenous regional anesthesia, D. Spinal anesthesia', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Refer :Sho textbook of Anesthesia by Ajay Yadav 2/e p 148 Prevention of conditions that our sickling is the basis of Peri operative management Supplemental oxygen is recommended Circulatory stasis can be prevented with hydration Normothermia is desirable The use of tourniquet and hence Biers block is contraindicated', 'role': 'assistant'}]