Effects of normothermia versus hypothermia on extravascular lung water and serum cytokines during cardiopulmonary bypass: a randomized, controlled trial.
OBJECTIVE
To evaluate the influence of perfusion temperature on the systemic effects of cardiopulmonary bypass (CPB), including extravascular lung water index (EVLWI), and serum cytokines.


METHODS
Prospective, randomized, controlled study.


METHODS
Cardiothoracic intensive care unit of a university hospital.


METHODS
Patients undergoing elective coronary artery bypass grafting.


METHODS
Twenty-one patients undergoing elective coronary artery bypass grafting were randomly assigned to receive either normothermic bypass (36 degrees C, n = 8) with intermittent antegrade warm blood cardioplegia (IAWBC), or hypothermic (32 degrees C, n = 13) CPB with cold crystalloid cardioplegia.


RESULTS
Mean arterial pressure, heart rate, cardiac output, systemic vascular resistance, mean pulmonary arterial pressure, and pulmonary vascular resistance were determined at baseline, i.e., after induction of anesthesia but before sternal opening (T-1), at arrival in the intensive care unit (T0), and 4 hrs (T4), 8 hrs (T8), and 24 hrs (T24) after surgery. EVLWI, intrathoracic blood volume index (ITBVI), and EVLW/ITBV ratio were obtained by using thermal dye dilution utilizing an arterial thermistor-tipped fiberoptic catheter and were recorded at T-1, T0, T4, T8, and T24. Serial blood samples for cytokine measurements were obtained at each hemodynamic measurement time point. Before, during, and after CPB, there were no differences in the conventional hemodynamic measurements between the groups. There were no changes in EVLWI up to T8 in either group. Furthermore, no change in the ratio EVLW/ITBW was observed between the groups at any time, further indicating the absence of a change in pulmonary permeability. Plasma levels of interleukin-6, tumor necrosis factor-alpha, and interleukin-10 increased during and after CPB, independently of the perfusion temperature.


CONCLUSIONS
Normothermic CPB is not associated with additional inflammatory and related systemic adverse effects regarding cytokine production and EVLWI as compared with mild hypothermia. The potential temperature-dependent release of cytokines and subsequent inflammation has not been observed and normothermic CPB may be seen as a safe technique regarding this issue.
Honore
P M
PM
Cardiothoracic Intensive Care Unit, St-Luc Teaching Hospital, Brussels, Belgium. Pathonor@skynet.be
Jacquet
L M
LM
Beale
R J
RJ
Renauld
J C
JC
Valadi
D
D
Noirhomme
P
P
Goenen
M
M
D000328:Adult; D001834:Body Water; D002314:Cardioplegic Solutions / Q000494:pharmacology*; D002315:Cardiopulmonary Bypass / Q000009:adverse effects / Q000379:methods*; D003325:Coronary Care Units; D016207:Cytokines / Q000378:metabolism*; D017558:Elective Surgical Procedures; D005260:Female; D005500:Follow-Up Studies; D006439:Hemodynamics / Q000502:physiology; D006801:Humans; D007036:Hypothermia, Induced; D018836:Inflammation Mediators / Q000032:analysis*; D008168:Lung; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011336:Probability; D011446:Prospective Studies; D013696:Temperature; D016896:Treatment Outcome
D002314:Cardioplegic Solutions; D016207:Cytokines; D018836:Inflammation Mediators