Pulmonary EdemaRelated toChangesinColloid Osmotic andPulmonary Artery WedgePressure in Patients after AcuteMyocardial Infarction

SUMMARY Pulmonary artery wedgeandplasma colloid osmotic pressuresandtheir relationship topulmonary edema were investigated in26patients with acutemyocardial infarction ofwhom14developed pulmonary edema. Intheabsence ofpulmonary edema, boththepulmonary artery wedge pressureandplasma colloid osmotic pressurewere innormal range;after onsetofpulmonary edema, amoderate increase inpulmonary wedge pressureandreduction inplasma colloid osmotic pressurewere observed. Whenthegradient between theplasma colloid osmotic pressureandthepulmonary arterywedge pressurewas calculated, highly significant differences were demonstrated (P< 0.002). Intheabsence of pulmonary edema, this gradient averaged 9.7(+1.7SEX1) torr; following appearanceofpulmonary edema, itwas reduced to1.2(+1.3) torr.Duringtherapy withdigoxin andfurosemide, reversal ofpulmonary edema was closely related toa concomitant change inthecolloid osmotic-hydrostatic pressuregradient. These observations indicate that bothincreases inpulmonary capillary pressureanddecreases incolloid osmotic pressuremay follow theonsetofpulmonary edema. Suchdecline incolloid osmotic pressureandespecially thereduction incolloid osmotic-hydrostatic capillary pressuregradient may favor transudation of fluid intothelungs.