Effect of a catecholamine-induced increase in cardiac output on extravascular lung water.
OBJECTIVE
To determine the influence of dopamine- and dobutamine-induced increases in cardiac output on the extravascular lung water in an experimental model of pulmonary edema.


METHODS
Animal experimental study.


METHODS
Animal experimental laboratory of a tertiary hospital.


METHODS
Mixed-race pigs (n = 20) weighing 28-32 kg.


METHODS
After the animals were anesthetized and tracheotomized, they were injected with 0.1 mL/kg of oleic acid, producing a pulmonary edema by increased permeability. The animals then were randomized into two groups: Group I (n = 10) received no medication to alter cardiac output and remained on mechanical ventilation during the 240 mins of the experiment; group II (n = 10) received a continuous infusion of dopamine and dobutamine to produce a cardiac output increase of >or=30% the basal value and underwent the same mechanical ventilation regimen as group I.


RESULTS
Hemodynamic and respiratory variables were measured at 0 (baseline) and 30, 60, 120, 180, and 240 mins after the infusion of oleic acid. At 30 mins, the cardiac output of group II (5.40 +/- 0.94 L/min) was significantly (p < .005) higher than that of group I (3.65 +/- 1.02 L/min), and a similar significant increase was recorded at all measurement times until the end of the experiment. The mean pulmonary arterial pressure was similar in both groups except that at 240 mins it was significantly higher in group I (normal cardiac output) than in group II (high cardiac output; 34.9 +/- 7.9 mm Hg vs. 27.2 +/- 3.8 mm Hg, p = .01). The extravascular lung water was calculated by gravimetric method after the death of the animal. The extravascular lung water of group I (13.8 +/- 3.6 mL/kg) did not significantly differ from that of group II (11.5 +/- 4.0 mL/kg).


CONCLUSIONS
An increase in cardiac output experimentally produced by the infusion of dopamine and dobutamine does not modify the amount of extravascular lung water.
García-Delgado
M
M
Department of Emergency and Critical Care, Virgen de las Nieves University Hospital, Granada, Spain. efermonde@hvn.sas.cica.es
Colmenero-Ruiz
M
M
Fernández-Sacristán
M A
MA
Rus-Mansilla
C
C
Fernández-Mondéjar
E
E
D000818:Animals; D002302:Cardiac Output / Q000187:drug effects*; D002316:Cardiotonic Agents / Q000494:pharmacology*; D004280:Dobutamine / Q000494:pharmacology*; D004298:Dopamine / Q000494:pharmacology*; D015633:Extravascular Lung Water / Q000187:drug effects*; D006439:Hemodynamics / Q000187:drug effects; D019301:Oleic Acid / Q000633:toxicity; D011654:Pulmonary Edema / Q000139:chemically induced / Q000378:metabolism*; D013552:Swine
D002316:Cardiotonic Agents; D019301:Oleic Acid; D004280:Dobutamine; D004298:Dopamine