This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Liver, Subject name: Surgery
[{'content': 'Which of the following is the most common acid-base disturbance in patients with cirrhosis and poal hypeension? \nSelect and explain. \nA. Metabolic acidosis., B. Respiratory alkalosis., C. Metabolic alkalosis., D. Respiratory acidosis.', 'role': 'user'}, {'content': 'Answer: C \nExplanation: - Metabolic alkalosis and hypokalemia are common in patients with cirrhosis because they often have associated secondary hyperaldosteronism (especially those with ascites), diarrhea, and frequent emesis. - Hyperaldosteronism enhances H+ and K+ exchange for Na+ in the distal tubule of the kidney. - The cause of diarrhea in patients with cirrhosis is unknown, but malabsorption secondary to splanchnic venous hypeension may be a contributing factor. - Emesis is common in alcoholic cirrhotics & patients with tense ascites. - Deleterious effects of metabolic alkalosis include impaired tissue oxygen delivery secondary to shift of oxyhemoglobin dissociation curve to the left & conversion of ammonium chloride to ammonia, which may contribute to encephalopathy.', 'role': 'assistant'}]