Effect of moderate altitude on the effect of mouth-to-mouth ventilation on blood gas analysis.

by spirometry and thoracic gas volume measured by body plethys¬ mography are identical, then it is the result of a suboptimal patient effort. The point of this case was that it is the degree of compres¬ sion, which is diagnostic. Although we also agree that both dynamic and fixed airway ob¬ struction could cause thoracic compression, we are unaware of studies relating to the latter. We certainly do not expect the degree of compression as seen in our patient to be present in patients with purely fixed obstruction. This belief is supported by a recent case of a tracheal obstruction (due to tracheal web), which was associ¬ ated with fixed obstruction, good effort, and no evidence of an ab¬ normal compression artifact. Thus, we agree that the specificity of the compressed volume measurement for dynamic collapse needs further investigation by studying patients with fixed obstruction. We also are not aware of any clinical trials in treating airways collapse. Base on our clinical experience, purse lip breathing is not obvious to some patients and thus may need to be taught. Although we agree that such trials need to be perform to determine efficacy of continuous positive airway pressure in airways collapse, practical considerations often necessitate individual therapeutic trial in recalcitrant symptomatic patients. forgotten detail of maintaining airway access after extubation of a difficult airway. Their patient, a 14-year-old morbidly obese man, had sustained multiple injuries including a pulmonary contusion and a fractured occipital condyle. After 8 days of mechanical ven¬ tilation, his condition had improved to the point of allowing tracheal extubation. Had extubation not been successful, reintubation may have been unsuccessful, prolonged, or resulted in neurologic injury.