Comparison of conventional and high-frequency ventilation: oxygenation and lung pathology

Abstract

Physiol.: Respirat. Environ. Exercise Physiol. 55 ( 1): 131-138, 1983.-Oxygenation and lung pathology were compared during conventional (CMV) and high frequency (HFO) ventilation in an animal model of pulmonary injury. Adult rabbits (2-4 kg) were studied under general anesthesia. Following tracheostomy, pulmonary injury was induced by saline lavage. During 5 h of either HFO or CMV, HFO produced a marked improvement in oxygenation (407, 407, and 409 Torr at 1, 3, and 5 h, respec-tively) compared with CMV (98, 129, and 87 Torr; P < 0.005). After 5 h each animal was killed and the lungs were fixed for microscopy. All CMV animals developed diffuse hyaline mem-branes, whereas the HFO animals did not. In a second series of experiments, HFO and CMV were attempted for 20 h. All CMV animals died before 20 h, [mean time of death = 10.6 h, final arterial blood O2 partial pressure Pao, = 56 Torr, arterial