Retransfusion acidosis after brief haemorrhagic hypotension in the dog.

Dogs under chloralose anasthesia were bled at a rate of 50 ml/min to a total of 25 ml/kg body weight and 2 minutes later a quick reinfusion of adequate volumes of blood, dextran, or Locke's solution was done. Within 2 minutes after reinfusion, the pH of arterial blood fell by 0.074--0.127; concurrently, PaCO2 rose by 9.2-12.9 mm Hg. A close correlation was demonstrated between these changes. After retransfusion, PaO2 and the arterial lactic acid level did not change significantly. Thus retransfusion acidosis in the dog appears after a brief hypotensive period, too, but cannot be attributed to a "washout" of lactate from the tissues.