TY - JOUR
T1 - Blood concentrations of enflurane before, during, and after hypothermic cardiopulmonary bypass
AU - Goucke, Roger
AU - Hackett, L.P.
AU - Barrett, Hugh
AU - Ilett, Kenneth
PY - 2007
Y1 - 2007
N2 - Objective: The purpose of this study was to determine blood concentrations of enflurane delivered via a membrane oxygenator during hypothermic cardiopulmonary bypass (CPB) with changes in the input enflurane concentration and temperature and to characterize the pharmacokinetics of enflurane washout during and after CPB.Design: Blood enflurane concentrations were measured by gas chromatography before, during, and after CPB by using mean delivered enflurane concentrations of 0.5% v/v (group 1, n = 5), 0.8% (group 2, n = 7), and 1% (group 3, n 14).Setting: The investigation was performed in a teaching hospital setting.Participants: Twenty-six patients undergoing cardiac surgery requiring hypothermic CPB.Interventions: Variations in input enflurane concentration in different patients plus blood sampling from the arterial side of the circuit for enflurane assay.Measurements and Main Results: Median (25th and 75th percentiles) pre-CPB blood enflurane concentrations were 48 (25-50) mg/L, 52 (47-56) mg/L, and 115 (90-143) mg/L in groups 1 (0.5% v/v), 2 (0.8% v/v), and 3 (1% v/v), respectively. During hypothermia (28 degrees C) corresponding enflurane concentrations were 44 (31-53) mg/L, 56 (45-62) mg/L, and 145 (109-203) mg/L, respectively. For groups 1 and 2, there were no significant changes in blood enflurane compared with the corresponding pre-CPB value. However, for group 3, cooling resulted in a significant increase (p = 0.006) in blood enflurane. In all groups, enflurane concentrations after rewarming were similar to those in the pre-CPB period.Conclusions: It is concluded that exposure to enflurane concentrations greater than 0.8% during CPB can result in high blood concentrations. (c) 2007 Elsevier Inc. All rights reserved.
AB - Objective: The purpose of this study was to determine blood concentrations of enflurane delivered via a membrane oxygenator during hypothermic cardiopulmonary bypass (CPB) with changes in the input enflurane concentration and temperature and to characterize the pharmacokinetics of enflurane washout during and after CPB.Design: Blood enflurane concentrations were measured by gas chromatography before, during, and after CPB by using mean delivered enflurane concentrations of 0.5% v/v (group 1, n = 5), 0.8% (group 2, n = 7), and 1% (group 3, n 14).Setting: The investigation was performed in a teaching hospital setting.Participants: Twenty-six patients undergoing cardiac surgery requiring hypothermic CPB.Interventions: Variations in input enflurane concentration in different patients plus blood sampling from the arterial side of the circuit for enflurane assay.Measurements and Main Results: Median (25th and 75th percentiles) pre-CPB blood enflurane concentrations were 48 (25-50) mg/L, 52 (47-56) mg/L, and 115 (90-143) mg/L in groups 1 (0.5% v/v), 2 (0.8% v/v), and 3 (1% v/v), respectively. During hypothermia (28 degrees C) corresponding enflurane concentrations were 44 (31-53) mg/L, 56 (45-62) mg/L, and 145 (109-203) mg/L, respectively. For groups 1 and 2, there were no significant changes in blood enflurane compared with the corresponding pre-CPB value. However, for group 3, cooling resulted in a significant increase (p = 0.006) in blood enflurane. In all groups, enflurane concentrations after rewarming were similar to those in the pre-CPB period.Conclusions: It is concluded that exposure to enflurane concentrations greater than 0.8% during CPB can result in high blood concentrations. (c) 2007 Elsevier Inc. All rights reserved.
U2 - 10.1053/j.jvca.2006.08.009
DO - 10.1053/j.jvca.2006.08.009
M3 - Article
C2 - 17418735
VL - 21
SP - 218
EP - 223
JO - Journal of Cardiothoracic and Vascular Anaesthesia
JF - Journal of Cardiothoracic and Vascular Anaesthesia
SN - 0888-6296
IS - 2
ER -