Pulmonary effects of crystalloid and colloid resuscitation from hemorrhagic shock in the presence of oleic acid-induced pulmonary capillary injury in the dog.

The effects of resuscitation with crystalloid and colloid solutions in the presence of increased pulmonary capillary permeability were studied. Twenty-four hours after oleic acid administration, dogs were anesthetized and bled to produce hemorrhagic shock. One hour later, resuscitation was performed with saline, 5% albumin, or 6% hydroxyethyl starch solution to restore and then maintain cardiac output at pre-oleic acid values for 6 h. Dogs were recovered and, 24 h later, were reanesthetized for final measurements. Oleic acid administration resulted in increases in pulmonary artery pressure, pulmonary vascular resistance, and extravascular lung water (EVLW). Resuscitation from hemorrhagic shock restored pulmonary hemodynamics to pre-hemorrhage levels and did not affect EVLW, PaO2, shunt fraction, dead-space-to-tidal-volume ratio, or pulmonary compliance. There were no differences in these parameters related to the choice of resuscitation fluid. Saline resuscitation markedly reduced plasma oncotic pressure and the plasma oncotic-pulmonary artery occlusion pressure gradient. Values for these two variables were markedly lower with saline than with colloid resuscitation. The authors conclude that the pulmonary effects of crystalloid and colloid solutions are similar in the presence of moderate increases in pulmonary capillary permeability.