ABSTRACT

Previously in low-pressure pulmonary edema (LPPE) induced with oleic acid (OA) in isolated lobes, we achieved edema reabsorption with 6% Hetastarch (HTS) a colloidal plasma expander.^1,2 In this study, this approach was tested in intact animals. Severe LPPE was produced in 19 dogs with intravenous OA (0.075 mg/kg). Two hours later, dogs were randomized into a control (n = 9) and a treatment group (n = 10). In the treatment group, HTS was infused to maintain oncotic pressures (COP) at COP > 30 mmHg. This required ultra filtration of excess fluid to sustain pulmonary wedge pressure (PWP) at baseline levels. To control for the effects of ultrafiltration, non-treated HTS dogs (controls) were infused normal saline and were ultrafiltered to maintain comparable PWP. In the HTS treated animals, COP rose to 34.7 ± 10, compared to 5.1 ± 3.2 mmHg in controls. There were no differences in PWP. Although significant HTS extravasations occurred suggested by dry weight of treated lungs 2.84 ± 0.29 compared to controls 2.33 ± 0.3 g/kg.dog.weight, (p < 0.05), edema was significantly improved in HTS treated animals, as deduced from a significant reduction in pulmonary wet weight 24.9 ± 5.8 g/kg dog weight in comparison with control group 34.3 ± 11.8 (p < 0.05). The administration of HTS reduced the edema formation in severe LPPE secondary to OA but not enough to significantly improve gas exchange.

KEYWORDS

Pulmonary edema, oleic acid, Hetastarch..

REFERENCES

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