Metabolic effects of vagotomy and gastric drainage C . WASTELL

IN 1943 Dragstedt & Owens changed the established surgical treatment for chronic duodenal ulceration by re-introducing the operation of vagotomy. It was rapidly recognized that, together with vagotomy, a gastric drainage procedure of some type was essential (Dragstedt & Schafer, 1945). In its early years, vagotomy and drainage rapidly gained in popularity on the basis of simplicity and the low operative mortality of 0-1-7% (Everson et al., 1957; Burge & Pick, 1958; Hamilton et al., 1961; Hendry, 1961), together with a low incidence of post gastric surgery sequelae such as dumping and bilious vomiting. Recently the nutritional hazards of partial-gastrectomy have become recognized (Stammers & Williams, 1963) and it is natural therefore that this aspect of vagotomy and drainage should be closely examined. This paper is principally concerned with reviewing the information we possess about the metabolic and nutritional effects of vagotomy and drainage. There has been a tendency in the past to consider post-vagotomy nutritional results regardless of the type of gastric drainage used. This is an assumption that, with the knowledge we at present have, is not justified. There are theoretical advantages to performing pyloroplasty as opposed to gastro-jejunostomy; correct sequential mixing of gastric chyme, digestive juices and bile together with appropriate hormonal control by gastrin, secretin and cholecystokinin. In addition the duodenum may be important for the absorption of certain food materials, notably, iron (Wheby, Jones & Crosby, 1964). Gastro-jejunostomy, while being technically possible in all cases, has the disadvantage, in addition to duodenal bypass, of the formation of a blind-loop. Usually this does not cause nutritional problems but occasionally it may lead to malabsorption of fat and vitamin B12, which will be discussed later. Another possible variant, relevant to nutrition, is that of selective vagotomy. This technique, introduced by Franksson (1948) and Jackson (1948), consists of preservation of all extra-gastric vagal nerve fibres. Its exponents point out that gall bladder innervation is preserved (Harkins et al., 1963) thus preserving normal contractility (Johnson & Boyden, 1952; Rudick & Hutchison, 1964). In addition the blunting and loss of the tips of the jejunal villi seen in dogs after total vagotomy (Ballinger et al., 1965), is prevented. With these possible technical variations in mind the subject will be considered under the following headings: weight; fat, protein and carbohydrate absorption; haematological status and bone disease.