Perioperative renal failure: hypoperfusion during cardiopulmonary bypass?
Acute renal failure is one of the most frequent and life-threatening complications after cardiac surgery. There is a recent growing deal of information suggesting that during the time of cardiopulmonary bypass kidneys may suffer from an imbalance between oxygen supply and oxygen needs. A low hematocrit during cardiopulmonary bypass is associated with an increase risk of acute renal failure, mainly due to a low oxygen delivery. An inadequate oxygen delivery during cardiopulmonary bypass is associated with lactate production, and under normothermic conditions, hyperlactatemia appears for an oxygen delivery below 260 mL min(-1) m(-2). The risk of acute renal failure significantly increases for an oxygen delivery approximately at the same value (272 mL min(-1) m(- 2)). During cardiopulmonary bypass, the pump flow should be coupled with the hematocrit to avoid falling below this critical oxygen delivery.
Ranucci
Marco
M
Department of Anestesia and Intensive Care, IRCCS Policlinico S. Donato, San Donato Milanese, Milan, Italy. cardioanestesia@virgilio.it
D058186:Acute Kidney Injury / Q000209:etiology*; D002315:Cardiopulmonary Bypass / Q000009:adverse effects*; D006400:Hematocrit; D006801:Humans; D007431:Intraoperative Complications; D007668:Kidney / Q000378:metabolism / Q000473:pathology; D019344:Lactic Acid / Q000097:blood; D010100:Oxygen / Q000008:administration & dosage* / Q000378:metabolism; D012307:Risk Factors
D019344:Lactic Acid; D010100:Oxygen