Renal Function and the Azotemia following Hematemesis.

Elevation of the blood urea nitrogen following massive hemorrhage from the stomach and duodenum is a frequent occurrence (1). Its mechanism is not the same as that associated with high intestinal obstruction, as it occurs in the absence of any vomiting (2) (e.g. in the presence of melena alone4), and is associated with a normal or increased blood chloride concentration (3, 4, 5) and a normal carbon dioxide combining power of the blood (4, 5). The factors contributing to this increase of the urea nitrogen content of the blood have been said to comprise shock, dehydration, starvation, renal insufficiency, and absorption of decomposition products of the blood liberated in the intestinal tract. We have elsewhere adduced evidence which excludes the factors of shock, dehydration, and starvation as essential but which emphasizes the importance of the digestion of the blood in the intestinal tract (1, 6). Attempts have previously been made to evaluate the renal factor in this increase of the blood urea nitrogen. Sanguinetti (7) found that three patients with elevated blood urea content following hematemesis were able to excrete a concenration of 30 to 38 grams of urea per liter of urine and believed that this excluded renal insufficiency. Christiansen (2) reported normnal kidneys at necropsy in a case of hematemesis (due to peptic ulcer) in which there was an abnormally high blood urea concentration. Ingegno (8) emphasized the presence of normal blood pressure, high urine specific gravity, and negative urinary find-