The effects of ethchlorvynol on pulmonary alveolar membrane permeability.

Intravenous injection of ethchlorvynol (Placidyl) causes noncardiogenic pulmonary edema in humans and laboratory animals. We studied the effects of intravenous ethchlorvynol (15 to 25 mg per kg of body weight) on pulmonary alveolar membrane permeability to various endogenous and exogenous solutes in the in vivo saline-filled dog lung model. Baseline and postethchlorvynol times in minutes for 50 per cent equilibration between the blood and saline-filled alveoli were, respectively, for urea, 37.3 +/- 12.4 and 12 +/- 6.3; for albumin 8,160 +/- 4,400 and 267 +/- 93; for dextrans of molecular weight 10,400 daltons, 1,150 +/- 80 and 185 +/- 160; for dextrans of molecular weight 250,000 daltons, 24,000 +/- 800 and 1,120 +/- 900; for dextrans of molecular weight 500,000 daltons, 24,500 +/- 150 and 1,020 +/- 590. All of these pairs of values were significantly different (P less than 0.01). In addition, lung liquid histamine (but not blood histamine) concentrations increased significantly (P less than 0.001) after ethchlorvynol injection. Intravenous ethchlorvynol causes marked increases in alveolar membrane permeability.