Paroxysmal Pulmonary Edema

Abstract

We have studied pulmonary edema following rapid infusion of massive doses of fluid into the circulation of dogs. Infusion into either the femoral or the jugular veins, or the femoral arteries was tried in 14 dogs with inconstant results. The rapid infusion of fluid into the carotid arteries toward the brain was therefore used to induce pulmonary edema constantly.

Technique. Experiments were performed on 18 dogs weighing from 8 to 20 kg, under morphine (3 mg/kilo)-urethane (1 g/kilo) anesthesia. Infusions were given simultaneously into both carotid arteries under a pressure of 280-300 m/m Hg. The total quantity of fluid injected amounted to 2.3 times the animal's estimated blood volume (on the basis of an assumed blood volume equal to 10% of body weight). A firt infusion amounted to 85% of the blood volume and required from 1 to 2.5 minutes. A second infusion equivalent to 80% was given 10 minutes later. A third infusion equivalent to 65% of the blood volume was given 5 minutes after the end of the second. It the animal survived, it was sacrificed 7 minutes after the end of the last infusion.

Edema of the lungs was evaluated by: (a) weighing the lungs and calculating the lung/body index; (b) examining the gross appearance of the lungs and the presence of foam in the trchea; (c) studying the fluid pouring out of the cut parenchyma. Venous pressure, arterial pressure, X-ray of the chest and electro- and phonocardiograms were studied in some animals.