{'fraction_non_alphanumeric': 0.018879415347137638, 'fraction_numerical': 0.013398294762484775, 'mean_word_length': 4.826241134751773, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Perfusate qualities and spontaneous edema formation in an isolated perfused lung preparation.

In isolated perfused lung preparations spontaneous edema tends to develop with time of perfusion. Such edema is probably in most cases due to a gradual increase in capillary permeability. In the present work some aspects of the relationship between perfusate qualities on the one hand and spontaneous development of edema on the other have been investigated in an isolated, ventilated and perfused rabbit lung preparation. Perfusion with plasma at 38° C preserved the preparations for a variable length of time. In some cases edema developed within 2 h, in other preparations, however, definite edema did not develop within 6 h of perfusion. With plasma as perfusate at 28° C there were invariably no signs of edema in the course of a 6 h perfusion period. When 4% (w/v) albumin in a Krebs Ringer solution was used as a perfusate at 38° C, massive edema was always formed within 2 h of perfusion. This development was somewhat retarded when the same perfusate was used at 28° C. In confirmation of previous findings the presence of erythrocytes in the perfusate was found to prolong the survival time of the preparations. The time interval prior to edema formation was thus significantly increased when erythrocytes were added to the perfusate of 4% albumin in Krebs Ringer solution. The effect was more marked with an hematocrit of 30–40 % than with one of 10–11 %. The results indicate that the maintenance of normal capillary permeability is dependent upon some form of biochemical interplay between the perfusate and the capillary endothelium.