Acid-base status and blood gas alterations following experimental uremia in cattle.

Experimental uremia created by obstructing the urethra of 7 cross-bred bulls was associated with significant (P less than 0.05) increases in PCV, blood urea nitrogen concentration, arterial and venous pH and PCO2, arterial bicarbonate, and base excess. Total serum protein concentration decreased nonsignificantly. Arterial PO2 reduced significantly during later stages of uremia. Arterial and venous oxygen saturation, arteriovenous oxygen difference, oxygen extraction ratio, and arteriovenous pH difference were not affected significantly. Uremia was characterized by progressive metabolic alkalosis with, as a compensation, hypercapnia, and arterial hypoxemia. There was no evidence of systemic shunting of blood except in 1 animal.