Pharmacokinetics of analgesics, sedatives and anaesthetic agents during cardiopulmonary bypass

Abstract

CPB produces changes in the blood-gas partition coefficient dependent on the prime used and temperature. Fortunately, the overall effect for hypothermic CPB and a crystalloid prime is only +2%. A volatile agent started during hypothermic CPB takes longer to equilibrate and agents already in use need to re-equilibrate, potentially changing the depth of anaesthesia, until equilibration is complete. As these agents are metabolized to a small degree and washout is fast, the duration of action is not prolonged after CPB.