Ventilation at supraphysiologic frequencies. Theoretical, technical, experimental, and clinical basis
This presentation summarizes the most common forms of ventilation at supraphysiologic frequencies. All techniques are technically fascinating, exciting for the physiologist, and have proven valuable for selected clinical applications, such as HFPPV in the operating room or HFJV in airway disruption. None of these modalities of mechanical support has resulted in a major improvement in the anticipated outcome of acute respiratory failure. These observations should not be surprising, since mechanical ventilation is not a therapy for acute respiratory failure, but only a form of symptomatic support. A decisive reduction in the unaccceptably high mortality rate of acute respiratory failure will only be achieved through increased understanding of alveolar and capillary lesions at the microcellular level. The pharmacologist and biochemist, not the pneumatic and electronic engineer, will be responsible for the final step.