Insulin responsetocarbohydrate ingestion after gastric surgerywith special reference tohypoglycaemia

SUMMARY Factors responsible forspontaneous hypoglycaemia wereinvestigated in23gastrectomy patients andtwopatients withvagotomyandpyloroplasty. Plasma insulin andcapillary blood glucose levels were followed after giving 175mlof50%glucose orally. Ingastrectomy patients a significant correlation was found between theheight ofthepeakblood glucose andinsulin levels for thesame individual. Patients withhighpeakglucose andinsulin levels were significantly more likely todevelop hypoglycaemia later inthetest. These findings arecompatible withthesuggestion that themajor factor predisposing tohypoglycaemia isafaster than averagerateofemptying ofthe gastric remnant, butthis doesnotexplain alltheresults. Intwocases,hypoglycaemia followed an abnormally large insulin responsetooral glucose. Theresults ofinsulin injection tests in14patients donotexclude thefurther possibility that insome caseshypoglycaemia isduetoexcessive insulin sensitivity.