LONG-TERM METABOLIC ADVANTAGES OF A GASTROINTESTINAL COMPOSITE URINARY RESERVOIR

Purpose: We investigated the long-term metabolic impact of gastrointes tinal composite reservoirs, Materials and Methods: Nine patients under went construction of a gastroileal (7) or gastrocolonic (2) reservoir for continent urinary diversion. Four cases of metabolic acidosis were converted from a preexisting conduit and the other 5 patients had div ersion for either preexisting metabolic acidosis or the short bowel sy ndrome. All were reconstruct;ed using a medium sized gastric segment ( 8 x 4 cm.) from the greater curvature of the stomach. The anti-inconti nence segment was constructed from a tapered and reimplanted ileal seg ment. All patients underwent preoperative and postoperative measuremen ts of serum pH, serum electrolytes, and urinalysis, Serum gastrin was measured in all patients postoperatively. Followup from surgery ranged from 47 to 61 months (mean 54.4), Results: All 9 patients demonstrate d electrolyte neutrality in serum on long-term followup. Postoperative serum pH (mean 7.40) was significantly different (p<0,01) from preope rative serum pH (mean 7.36) and serum bicarbonate was also significant ly different (p<0.01) preoperatively versus postoperatively (mean 22,3 versus 25.14), Urine pH values were not significantly different throu ghout the study. One patient with mildly acidic urinary pH (6.0 to 6.5 ) had ulcerative skin changes at the stoma site, Three patients had el evated serum gastrin levels on short-term followup but all patients ha d normal serum gastrin levels on long-term followup. One patient, with persistent alkaline urine, had urolithiasis and symptomatic urinary t ract infections, Conclusions: Our results demonstrate that a composite urinary reservoir constructed using gastric and intestinal segments a chieved serum electrolyte neutrality on long-term followup. These resu lts indicate a long-term metabolic advantage over other intestinal res ervoirs associated with hyperchloremic metabolic acidosis and may be b eneficial in patients compromised by either preexisting metabolic acid osis or the short bowel syndrome.