Mechanical properties of isolated fetal miniature pig lungs after substitution with fluorocarbons.
In our present study we tried to inflate and stabilize isolated immature lungs of fetal minipigs in gestation age of 95 days (= 85% of total normal gestation period) with different fluorocarbons. Based on our previous experiences, the immature lungs at day 95 are almost non inflatable with air. For our experiments we used fluorocarbon 43 (FC-43) with a surface tension of 16 mN/m and fluorocarbon 72 (FC-72) with a surface tension of 12 mN/m. Eighteen fetal immature lungs were used. In group 1 the lungs were rinsed with FC-43; in group 2 the rinse solution was FC-72, and in group 3 the lungs were untreated. After removing the fluorocarbon, in the case of groups 1 and 2, the lungs were artificially ventilated. Pressure-volume (p-v) curves were registered in the beginning (immediately after FC lavage), after 10 and 20 min of artificial ventilation. Airway opening pressure (pi) and weight-specific end-inspiratory lung compliance (ci) were investigated. Statistically significant differences in weight-specific end-inspiratory compliance were found between FC groups and untreated group 3, but no stabilization could be seen during the investigation period of 20 min. No statistically significant improvement in weight-specific end-inspiratory compliance was observed between group 1 and 2, although the compliances of group 2 with FC-72 were better than those of group 1 with FC-43 in three p-v diagrams registered in the beginning and after 10 and 20 min of artificial ventilation.(ABSTRACT TRUNCATED AT 250 WORDS)
Widjaja
B
B
Institute of Pharmacology and Toxicology, Faculty for Clinical Medicine Mannheim, University of Heidelberg, Federal Republic of Germany.
Wuthe
J
J
Schmidt
A
A
Seitz
B
B
Rüfer
R
R
D000818:Animals; D005260:Female; D005333:Fetus / Q000502:physiology*; D005466:Fluorocarbons / Q000494:pharmacology*; D066298:In Vitro Techniques; D008168:Lung / Q000187:drug effects / Q000502:physiology*; D011247:Pregnancy; D011663:Pulmonary Surfactants / Q000502:physiology; D012121:Respiration, Artificial; D013047:Specific Pathogen-Free Organisms; D013500:Surface Tension; D013552:Swine; D013556:Swine, Miniature
D005466:Fluorocarbons; D011663:Pulmonary Surfactants