The Pathogenesis of Azotemia in Hemorrhage From the Upper Gastro-Intestinal Tract 1

Diagnostic evaluation of urea nitrogen/creatinine ratio in dogs with gastrointestinal bleeding

“…Forty dogs were prospectively enrolled. Of these, 25 dogs were excluded for the following reasons: no bleeding lesions identified (15), administration of corticosteroids ( 8), hepatic dysfunction (1), and marked muscle mass loss (1) corticosteroids were excluded from the study. No dogs were diagnosed with hyperadrenocorticism.…”

“…Experimental studies in people and dogs showed an association between ingestion of blood and increased serum urea concentration 12‐14 . An alternative hypothesis is that early prerenal azotemia associated with blood loss and subsequent hypovolemia causes increased serum urea concentration without an increase in serum creatinine concentration 14,15 . To our knowledge, the diagnostic value of the index to predict occult GIB and localize GIB has not been investigated in dogs.…”

Does Blood Urea Nitrogen Level Predict Severity and High-Risk Endoscopic Lesions in Patients with Nonvariceal Upper Gastrointestinal Bleeding?

“…A relationship between azotemia and gastrointestinal bleeding has been the main focus of many studies in the past (20)(21)(22)(23). Elevated BUN level in UGIB patients can be due to ingested blood protein, secondary to prerenal azotemia or renal failure.…”

Discussion on the Effects on the Kidney of Trauma to Parts other Than the Urinary Tract, Including Crush Syndrome

“…(a) Increased protein breakdown in the small gut gives rise to increased urea formation in the liver [14]: this increase depends directly on the rate of amino-acid absorption and on adequate de-amination by the liver.…”