EFFECT OF GASTRIC RESECTION, ROUX-EN-Y DIVERSION AND VAGOTOMY ON GASTRIC-EMPTYING IN THE RAT

Solid and liquid gastric emptying studies were conducted in 61 male Wi star rats. In 20 animals a two-thirds Polya-type gastric resection was performed and 21 had a similar resection with a IO-cm Roux-en-Y diver sion. In nine of the Roux diversions truncal vagotomy was also carried out. Twenty animals acted as controls: ten unoperated and ten that re ceived laparotomy only. Body-weight and gastric emptying were measured weekly for 4 weeks and monthly for 4 months after surgery. Animals su bjected to gastrectomy revealed a weight loss of approximately 16 per cent after operation. Weight gain was slower after Roux reconstruction than after Polya-type anastomosis and slowest in animals with vagotom y and Roux drainage (P<0.05). Gastric emptying was unchanged in unoper ated controls. Animals in which a laparotomy was performed had delayed solid and liquid emptying for the first 4 weeks after operation (P<0. 05). Following Polya-type gastrectomy, liquid emptying was delayed for 4 months. Solid emptying was unchanged, with no evidence of the delay present in animals with a laparotomy. Animals subjected to Roux-en-Y diversion showed a greater delay in liquid emptying than those with a Polya resection; solid emptying was also delayed (P<0.05). Severe gast ric retention of liquids and solids occurred in the early postoperativ e phase when vagotomy was added to the Roux diversion (P<0.01). Emptyi ng of solids adopted a relatively normal linear pattern after this ini tial retention. Emptying of liquids, however, remained abnormal, appea ring to adopt a biphasic pattern.