Atrial natriuretic peptide improves pulmonary gas exchange by reducing extravascular lung water in canine model with oleic acid-induced pulmonary edema.
OBJECTIVE
The purpose of this study was to examine and compare the effects of atrial natriuretic peptide and furosemide on pulmonary gas exchange, hemodynamics, extravascular lung water, and renal function in a dog model of oleic acid-induced pulmonary edema.


METHODS
Prospective, comparable, experimental study.


METHODS
Laboratory at a university hospital.


METHODS
Eighteen male beagle dogs were studied under mechanical ventilation with pentobarbital anesthesia.


METHODS
Oleic acid (0.08 mL/kg) was injected and allowed for 1 hr to achieve pulmonary edema with hypoxemia at Fio2 of 0.3. After lung injury, dogs were divided into three groups; control group (n = 6) receiving saline (2.5 mL/hr for 5 hrs), atrial natriuretic peptide group (n = 6) receiving atrial natriuretic peptide (1 microg x kg(-1) x min(-1) for 5 hrs), and furosemide group (n = 6) receiving furosemide (1 mg x kg(-1) x hr(-1) for 5 hrs).


RESULTS
Hemodynamics, arterial blood gases, extravascular lung water, and renal function were measured hourly for 7 hrs after injury. Oleic acid increased extravascular lung water and induced hypoxemia. In the atrial natriuretic peptide group, extravascular lung water was significantly (p <.05) lower and Pao2 was significantly (p <.05) higher than in the control and furosemide groups, respectively. Pulmonary hypertension induced by oleic acid was attenuated by atrial natriuretic peptide infusion but not by saline or furosemide. Increased natriuresis/diuresis did not significantly differ between the atrial natriuretic peptide and the furosemide group, whereas creatinine clearance in the atrial natriuretic peptide group was significantly higher than that in the furosemide group.


CONCLUSIONS
These findings suggest that atrial natriuretic peptide improves pulmonary gas exchange by reducing extravascular lung water and pulmonary arterial pressure, possibly independently from natriuresis/diuresis in oleic acid-induced pulmonary edema.
Department of Critical Care Medicine, Tokyo Medical and Dental University Graduate School, Tokyo, Japan. c.mitaka.icu@tmd.ac.jp
Chieko
C
Mitaka
Yukio
Y
Hirata
Kenichiro
K
Habuka
Yutaka
Y
Narumi
Kuninori
K
Yokoyama
Koshi
K
Makita
Takasuke
T
Imai
D000818:Animals; D009320:Atrial Natriuretic Factor / Q000494:pharmacology*; D004232:Diuretics / Q000494:pharmacology*; D004285:Dogs; D015633:Extravascular Lung Water / Q000187:drug effects*; D005665:Furosemide / Q000494:pharmacology*; D006439:Hemodynamics / Q000187:drug effects*; D007668:Kidney / Q000187:drug effects* / Q000503:physiopathology*; D008297:Male; D019301:Oleic Acid / Q000008:administration & dosage; D011654:Pulmonary Edema / Q000139:chemically induced / Q000503:physiopathology*; D011659:Pulmonary Gas Exchange / Q000187:drug effects*
D004232:Diuretics; D019301:Oleic Acid; D005665:Furosemide; D009320:Atrial Natriuretic Factor