What type of acid-base disturbance is associated with high-output uretosigmoidostomy?

High-output uretosigmoidostomy can lead to metabolic acidosis due to the loss of bicarbonate-rich urine through the sigmoid colon. When the kidneys no longer have a normal route for excretion, urination occurs through the gut, resulting in a unique situation where bicarbonate is lost along with urinary solutes.

In this scenario, large volumes of urine that are high in urea and electrolytes pass directly into the gastrointestinal tract. The colonic absorption of these solutes can lead to a deficit of bicarbonate, thereby creating a state of metabolic acidosis.

Additionally, patients with this condition often experience diarrhea, which can further contribute to bicarbonate loss and exacerbate the acidosis. This helps explain the connection between high-output uretosigmoidostomy and the development of metabolic acidosis, as the kidney's typical mechanism for maintaining acid-base balance is disrupted.