How gastric emptying of carbohydrate affects glucose tolerance and symptoms after truncal vagotomy with pyloroplasty.

It is commonly assumed that both abnormal glucose tolerance and postcibal symptoms after truncal vagotomy with pyloroplasty (V&P) are the result of rapid gastric emptying of carbohydrate; yet such correlations have not been established. These studies measured gastric emptying in symptomatic patients with V&P and normal subjects and sought correlations between rates of emptying and the time-courses of serum glucose and insulin as well as between emptying and symptoms. Gastric emptying in the V&P varied widely with different isocaloric meals of hypertonic glucose, taken in the erect vs. supine position, or of hypotonic starch taken in the erect posture as a solution or as solid balls of paste. Glucose and starch solutions were emptied abnormally rapidly in the erect posture, while glucose taken supine, and the starch balls were emptied more slowly. By contrast, all four meals emptied at about the same rates in the normal subjects. In both the V&Ps and the normals, there were weak correlations evident between the amount of carbohydrate emptied in the first 30 postcibal minutes and the rises in serum glucose or insulin. However, the presence or absence, the timing, and the qualitative nature of postcibal symptoms observed in the V&Ps did not correlate well with either the speed of emptying or the osmolarity of the carbohydrate meals.