Renal response to hemorrhage in dogs with subacute biliary obstruction

In the present study, we tested the hemodynamic and renal response of 15 sham-operated dogs and 15 dogs with subacute (5-9 days) biliary obstruction to either acute or more chronic hemorrhage. All studies were conducted on sedated but unanaesthetized animals. Both groups were comparable before blood withdrawal with respect to central hemodynamics and renal perfusion. Serum bilirubin was 0.70 +/- 0.09 mg/dL for control dogs and 8.25 +/- 0.14 for experimental dogs (P less than 0.05). In the acute protocol, nine control and seven jaundiced dogs were bled over a period of 30-40 min to lower blood pressure by 19.1 and 19.5%, respectively. Blood volumes required to achieve this drop were 21.3 and 20.05 mL/kg, respectively (P greater than 0.05). Cardiac output declined by an equivalent value for each group and glomerular filtration rate and clearance of p-aminohippurate remained unchanged from control values. In six control and eight experimental dogs, 500 mL of blood was withdrawn over 5 days. Although blood pressure and cardiac output declined for each group by an equivalent amount, renal perfusion remained unchanged for each group from control values. We conclude that acute or chronic hemorrhage of modest degree does not predispose to acute renal insufficiency in dogs with subacute biliary obstruction.