Effects of H 2 ‐receptor antagonist and selective muscarinic receptor antagonist on early gastric stagnation after pylorus‐preserving pancreaticoduodenectomy: Results of a randomized controlled study

The suppressive effects of an H 2 ‐receptor antagonist, ranitidine, and a selective muscarinic receptor antagonist, pirenzepine, in improving gastric stasis during the early postoperative period after pylorus‐preserving pancreaticoduodenectomy (PPPD) were assessed. Thirty‐two PPPD patients were divided into four groups of 8 patients each. Group 1 served as controls and were given no medication. Group 2 received i.v. ranitidine alone, group 3 received i.v. pirenzepine alone, and group 4 received i.v. ranitidine and pirenzepine combined. The daily volume and the total acidity of the gastric juice, aspirated via a nasogastric tube, were measured on post‐PPPD days 1–13. One patient in group 1 was withdrawn from this study due to severe gastric bleeding. The mean daily aspirated volume of gastric juice in group 1 ( n = 7) was 1043±362 ml on the 3rd postoperative day, and it gradually fell after the 5th postoperative day, but still exceeded 500 ml on day 13. In group 2 ( n = 8), the mean maximum volume, 614±251ml, was reached on the 4th postoperative day, and in group 3 ( n = 8), the mean maximum volume, 680 + 391 ml, was reached on the 3rd postoperative day. In contrast, in group 4 ( n = 8), the gastric juice output appeared to be suppressed and the mean maximum volume was 380±218 ml, this being reached on the 6th postoperative day. Gastric juice secretion was significantly higher in group 1 than in the other three groups ( P < 0.01). The total acidity was significantly lower in groups 3 and 4 than in group 1 ( P < 0.01). These results indicate that the postoperative administration of the combination of ranitidine and pirenzepine suppresses the volume and acidity of the gastric juice after a PPPD.