BACKGROUND: Victims of severe @entity2332 are prone to fluid extravasation but rarely develop @entity4 . We hypothesize that combined @entity2332 -induced increase in pulmonary vascular resistance (PVR) and a concomitant fall in cardiac output protect the lungs against @entity4 development. Our aim was to explore in hypothermic-isolated blood-perfused @entity35 lungs whether perfusion at constant pressure influences fluid filtration differently from perfusion at constant flow. METHODS: Isolated blood-perfused @entity35 lungs were hanging freely in a weight transducer for measuring weight changes (  W). Fluid filtration coefficient (Kfc), was determined by transiently elevating left atrial pressure ( @entity1989 ) by 5.8   mmHg two times each during normothermia (37  C) and during @entity2332 (15  C). The lung preparations were randomized to two groups. One group was perfused with constant flow (Constant flow group) and the other group with constant pulmonary artery pressure (Constant @entity67399 group). Microvascular pressure ( @entity22844 ) was determined before and during elevation of @entity1989 (  @entity22844 ) by means of the double occlusion technique. Kfc was calculated with the formula Kfc   =     W/  @entity22844 /min. All Kfc values were normalized to predicted lung weight (PLW), which was based on body weight (BW) according to the formula: PLW   =   0.0053   BW   -   0.48 and presented as KfcPLW in mg/min/mmHg/g. At cessation, bronchoalveolar lavage (BAL) fluid/perfusate protein concentration (B/P) ratio was determined photometrically. Data were analyzed with parametric or non-parametric tests as appropriate. p   <   0.05 considered as significant. RESULTS: Perfusate flow remained constant in the Constant flow group, but was more than halved during @entity2332 in the Constant @entity67399 group concomitant with a more fold increase in PVR. In the Constant flow group, KfcPLW and B/P ratio increased significantly by more than 10-fold during @entity2332 concerted by visible signs of @entity4 in the @entity825 . Hemoglobin and hematocrit increased within the Constant flow group and between the groups at cessation of the experiments. CONCLUSION: In hypothermic @entity35 lungs perfused at constant flow, fluid filtration coefficient per gram PLW and B/P ratio increased more than 10-fold concerted by increased hemoconcentration, but the changes were less in hypothermic lungs perfused at constant @entity67399 .

Effects of Constant Flow vs. Constant Pressure Perfusion on Fluid Filtration in Severe Hypothermic Isolated Blood-Perfused XXXX Lungs.

@entity825 :: ('MESH:D055090', 'Disease') :: ['trachea'] @entity4 :: ('MESH:D004487', 'Disease') :: ['lung edema', 'edema'] @entity1989 :: ('CHEBI:60159', 'Chemical') :: ['Pla'] @entity35 :: ('10116', 'Species') :: ['rat'] @entity22844 :: ('12181', 'Species') :: ['Pmv'] @entity67399 :: ('D010665', 'Chemical') :: ['PPA'] @entity2332 :: ('MESH:D007035', 'Disease') :: ['accidental hypothermia', 'hypothermia']
@entity35 :: (10116,Species) :: ['Rat']
