The effect of Roux-en-Y diversion on gastric and Roux-limb emptying in a rodent model

The effects of Roux-en-Y limb length on gastric emptying and enterogastric reflux in rats

PURPOSE

To assess the effects of Roux-en-Y jejunal limb length on gastric emptying and enterogastric reflux.

METHODS

Seventy male Wistar rats were submitted to antrectomy with Roux-en-Y reconstruction and then were divided into two groups of 35 animals. Group A, short limb (7.5 cm) and Group B, standard limb (15 cm). Group A and B were subdivided into five subgroups each in order to study enterogastric reflux at 30 and 60 minutes and to evaluate gastric emptying at 5, 10 and 15 minutes. In order to measure gastric emptying and enterogastric reflux, radiotracers 99m Tc-Phytate and 99m Tc-DISIDA were respectively used.

RESULTS

For gastric emptying, the radiotracer concentration was lower in Group A than in Group B after five minutes. The enterogastric reflux was present, but there were no significant differences between enterogastric reflux indexes concerning both A and B Groups.

CONCLUSION

A standard Roux limb, besides being unable to protect the stomach from the enterogastric reflux, may become a functional barrier for gastric emptying.

Evaluation of hepatobiliary excretion and enterobiliary reflux in rats with biliary obstruction submitted to bilioduodenal or biliojejunal anastomosis

Bilioduodenal and biliojejunal anastomoses are effective for the treatment of biliary obstruction. The objective of this study was to compare the effects of these anastomoses on hepatobiliary excretion and enterobiliary reflux. Enterobiliary reflux and biliary excretion were evaluated respectively after oral administration of technetium ((99m)Tc) in combination with sodium phytate and intravenous infusion of (99m)Tc with diisopropyl-iminodiacetic acid. Enterobiliary reflux occurred to an equal degree in the bilioduodenal and biliojejunal groups. Maximum hepatic activity time (T(max)) and radiotracer clearance half-time (T(1/2)) were similar in both groups. However, when compared with that found for the sham-operated group, T(max), and T(1/2) were higher in the biliojejunal group (P = 0.02 and P = 0.01, respectively). Histopathological analysis showed marked reduction in ductal proliferation in both groups. These data undermine the theoretical advantages attributed to biliojejunal anastomosis and further the understanding of the pathophysiology of cholangitis that occurs even with patent anastomosis.