Effects of intraoperative administration of atrial natriuretic peptide.
BACKGROUND
Biological activity of endogenous atrial natriuretic peptide (ANP) may decrease during cardiopulmonary bypass. To evaluate the effects of intraoperative administration of exogenous ANP in patients undergoing cardiopulmonary bypass, we conducted a prospective randomized study.


METHODS
Eighteen patients undergoing mitral valve surgery were randomized to receive either ANP treatment (ANP group; n = 9) or no ANP treatment (control group; n = 9). Atrial natriuretic peptide was given immediately after initiation of cardiopulmonary bypass for 6 hours (0.05 microg x kg(-1) x min(-1)). Plasma ANP, brain natriuretic peptide and cyclic guanosine monophosphate (cGMP) levels, hemodynamic variables and renal function were assessed perioperatively.


RESULTS
Administration of ANP increased plasma cyclic guanosine monophosphate levels, urine output and fractional sodium excretion, and decreased preload, afterload and plasma brain natriuretic peptide levels significantly (p < 0.05). Plasma cyclic guanosine monophosphate levels correlated with plasma ANP levels (r = 0.95, p = 0.0001), correlated with fractional sodium excretion (r = 0.53, p = 0.02), and correlated inversely with systemic vascular resistance (r = -0.54, p = 0.02).


CONCLUSIONS
Intraoperative administration of ANP had potent effects on natriuresis and systemic vasodilation by elevating cyclic guanosine monophosphate levels. The results suggest that the technique is useful for the management of hemodynamics and water-sodium retention after cardiopulmonary bypass.
Hayashida
N
N
Department of Surgery, Kurume University, Fukuoka, Japan. nobuhiko@med.kurume-u.ac.jp
Chihara
S
S
Kashikie
H
H
Tayama
E
E
Yokose
S
S
Akasu
K
K
Aoyagi
S
S
D000328:Adult; D000368:Aged; D009320:Atrial Natriuretic Factor / Q000008:administration & dosage*; D002315:Cardiopulmonary Bypass; D006152:Cyclic GMP / Q000097:blood; D004232:Diuretics / Q000008:administration & dosage*; D005260:Female; D019918:Heart Valve Prosthesis Implantation; D006801:Humans; D007432:Intraoperative Period; D008297:Male; D008875:Middle Aged; D008944:Mitral Valve Insufficiency / Q000601:surgery*; D008946:Mitral Valve Stenosis / Q000601:surgery*; D009318:Natriuresis / Q000187:drug effects; D010446:Peptide Fragments / Q000008:administration & dosage*; D011446:Prospective Studies; D014664:Vasodilation / Q000187:drug effects
D004232:Diuretics; D010446:Peptide Fragments; D009320:Atrial Natriuretic Factor; D006152:Cyclic GMP