THE SHORT-TERM EFFECTS OF INCREASING PLASMA COLLOID OSMOTIC-PRESSURE IN PATIENTS WITH NONCARDIAC PULMONARY-EDEMA

  • 1 January 1983
    • journal article
    • research article
    • Vol. 93  (5) , 620-633
Abstract
Hyperoncotic albumin (25 or 50 g of a 50% solution) was infused into patients with noncardiac pulmonary edema (adult respiratory distress syndrome [ARDS]) to evaluate its effect on the transmicrovascular flux from blood to pulmonary edema fluid of 2 radiotracers: 111In-DTPA [diethylenetriaminepentaacetic acid] (MW 504) and 125I-human serum albumin (HSA) (MW 69,000). Two groups of patients were studied, one with a modest increase in permeability of the pulmonary alveolocapillary membrane to 125I-HSA (group 1) and another with a large increase in permeability to 125I-HSA (group 2). Furosemide was used when necessary to minimize the effect of albumin infusion to increase the pulmonary microvascular hydrostatic pressure (Pmv), measured clinically as the pulmonary capillary wedge pressure (PCWP). Therapy significantly increased the mean colloid osmotic pressure (COP) in both groups, but not the mean PCWP or calculated Pmv. Albumin had no significant effect on the mean pulmonary transmicrovascular flux of the radiotracers in either group, despite the increase in COP. In individual patients, a change in the Pmv in response to albumin infusion was directly correlated with the change in flux of 111In-DTPA [group 1: .DELTA.In-DTPA (%) = 8.66 + 1.4 .DELTA.Pmv (%) r = 0.51, P < 0.02; group 2: .DELTA.In-DTPA (%) = -3.43 + 1.6 .DELTA.Pmv (%) r = 0.67, P < 0.01]. A change in the transmicrovascular flux of I-HSA also correlated with a change in the intravascular Starling forces in both groups. Apparently albumin infusion in patients with ARDS will not augment the pulmonary transmicrovascular flux of low or high MW solutes when the effect of albumin to increase the Pmv is minimized; an increase in plasma COP does not significantly reduce the flux of such solutes.