Atrial natriuretic factor in normothermic and hypothermic cardiopulmonary bypass.
BACKGROUND
To evaluate the plasmatic changes of atrial natriuretic factor (ANF) during and after cardiopulmonary bypass (CPB) in normothermia and hypothermia.


METHODS
Twenty-three patients (n = 23) undergoing coronary artery bypass graft surgery were randomly assigned to two groups. In Group I (n = 11), the patients underwent operation in normothermia; in Group II (n = 12), the operation was performed in hypothermia (26 degrees C).


RESULTS
Plasma ANF levels were determined after induction of anaesthesia, at the end of CPB and one hour postoperatively. There were no demographic differences between the two groups, diuresis (p = 0.90) and natriuresis (p = 0.95). Plasma levels of ANF were significantly elevated during and after CPB in both groups (p < 0.01). The groups differed significantly for plasma levels of ANF during CPB and postoperatively (p < 0.05), but did not differ prebypass (p = 0.08). There was no correlation in either group between ANF release and central venous pressure, natriuresis and diuresis. There was only a borderline relationship between ANF concentration and diuresis after CPB in Group I.


CONCLUSIONS
CPB triggers the production and release of ANF. The present study demonstrates a significantly enhanced ANF release during hypothermia and reperfusion after ischaemia. Thus, these data suggest the protective role of ANF on the hypoxic myocardium, and they confirm that ANF does not play a role in diuresis and natriuresis during and after hypothermic CPB.
Brancaccio
Gianluca
G
Department of Pediatric Cardiac Surgery, Bambino Gesù Hospital, Rome, Italy. gbrancaccio70@hotmail.com
Michielon
Guido
G
Di Donato
Roberto M
RM
Costa
Dina
D
Falzea
Fabio
F
Miraldi
Fabio
F
D000368:Aged; D009320:Atrial Natriuretic Factor / Q000097:blood*; D002315:Cardiopulmonary Bypass / Q000379:methods*; D005260:Female; D006439:Hemodynamics; D006801:Humans; D007036:Hypothermia, Induced / Q000009:adverse effects*; D016014:Linear Models; D008297:Male; D008875:Middle Aged
D009320:Atrial Natriuretic Factor