[Hepatic insufficiency and nutritional problems after major hepatobiliary surgery]

Abstract

Problems raised by major hepatobiliary surgery affect the total economy of the human body. The liver is implicated in all body metabolism processes and possible problems during partial or total hepatectomy can only be solved by a knowledge of liver physiology. The liver plays a major role in the metabolism of products of digestion, whether these are carbohydrates or amino acids arriving in the portal blood. The most important activity of the liver is the preservation of a constant level of glucose by ensuring a fixed and predictable concentration to extrahepatic tissues. It ensures a very precise control of plasma and tissue flow of amino acids and thus protein synthesis and neoglycogenesis. Synthesis and degradation of non-esterified fatty acids, ketogenesis, cholesterol synthesis and triglyceride production result from the action of the liver on lipid metabolism. Free cholesterol is the precursor of bile acids and steroid hormones, but esterified cholesterol is not synthetized in the liver. Apart from its role in bilirubin metabolism, it has a key role to play in correct functioning of most endocrine systems: many are catabolized in the liver. But one of the most interesting properties of the hepatic tissue, as far as the surgeon is concerned, is liver regeneration, which combines hypertrophy with hyperplasia. This is dependent on age, hepatotrophic factors of portal blood, and extraportal factors. A study of hepatic metabolic processes allows assessment of the consequences of partial hepatectomy. Postoperative hypoglycemia, in the absence of a continuous infusion of glucose, is easily explained by the weakness of hepatic reserves in glycogen. Albumin levels fall during the first 7-10 days after liver resection, but this hypo-albuminemia is often marked by the need to infuse large quantities of frozen fresh plasma to try to avoid lesions of the other specific proteins, which are coagulation factors. Lipid metabolism disorders are of little clinical consequence. Hepatic resection is being alarming when it involves 80 to 90% of the hepatic mass and menaces the life of the patient. The existence of a previous liver alteration worsens the consequences of major hepatobiliary surgery. Indications for hepatic resection must be weighed carefully in patients with cirrhosis, liver regeneration being totally absent after resection. Metabolic consequences of total hepatectomy followed by transplantation are identical in kind to those of partial hepatectomy but are increased in frequency and start during operation. Postoperative surveillance must be strict to avoid marked variations in glycemia with the risk of hypoglycemia, and variations in kaliemia.(ABSTRACT TRUNCATED AT 400 WORDS)