LUNG FLUID AND PROTEIN DYNAMICS IN UNANESTHETIZED SHEEP DURING ALVEOLAR HYPOXIA

Autor: Samuel L Selinger, Norman C. Staub, Roderic H. Phibbs, Richard P Bland, R. H. Demling
Rok vydání: 1974
Předmět:
Zdroj: Pediatric Research. 8:464-464
ISSN: 1530-0447
0031-3998
DOI: 10.1203/00006450-197404000-00747
Popis: To determine if hypoxia has a direct effect on pulmonary microvascular fluid and protein transfer, we measured steady-state lung lymph flow (Qlym) and protein transport (Qprot) in 7 unanesthetized sheep breathing 10% O2 in N2 for 4 hr and in 2 sheep breathing the same gas for 48 hr. We surgically prepared the animals to isolate and collect lung lymph and to measure mean pulmonary artery (Ppa) and left atrial (Pla) pressures. After recovery, the sheep breathed air through a tracheostomy for 2-4 hr, followed by 4 or 48 hr of hypoxia. In 12 4-hr studies, mean PaO2 fell from 97 to 38 torr; Ppa rose from 20 to 33 cmH2O; Qlym and Qprot were unchanged. During 48 hr hypoxia, with a sustained elevation in Ppa and a decline in Pla, Qlym and Qprot diminished progressively, with a decrease in the lymph-plasma protein ratio (L/P) from 0.70 to 0.60. We conclude that 4 hr of severe hypoxia did not increase lung fluid filtration or protein permeability, a finding supported by normal post-mortem histology and a mean extravascular lung water content of 4.27 ml/g dry bloodless lung. The decreased Qlym, Qprot and L/P during prolonged hypoxia are unexplained, but indicate that no increase in vascular permeability to plasma proteins occurred. [Supported in part by HL14201 (SCOR).]
Databáze: OpenAIRE