Since direct measurement of alveolar pressure
is not possible, a number of methods have been developed in the 20th century that have enabled indirect estimates of alveolar pressure
Positive end expiratory pressure (PEEP) is applied during the end of expiration to maintain the alveolar pressure
above atmospheric pressure.
SP-A is covered on the alveolus surface to decrease the surface tension, thus prevent alveolus collapse, and stabilize pulmonary alveolar pressure
This assumption allows a surrogate of alveolar pressure
, known as dynostatic pressure ([P.sub.dyn]), to be estimated as follows:
The causative events that led to pneumothorax in our case are hypothesized to be as follows: forceful coughing and severe bucking increased alveolar pressure
causing rupture of the alveoli;11 from there, air traveled along the pulmonary vascular sheaths, where it entered the mediastinum and formed pneumomediastinum; then, the air dissected through the Jinguang Du et al.
The presumed patho-physiology of acute cocaine medicated lung injury is believed to arise from a sequence of events that begin with inhalation induced bronschospasm, increased alveolar pressure
followed by alveolar rupture leading to interstitial emphysema and pneumomediastinum (3).
The flow-interruption method was based on the idea that during the transient interruption of expired airflow, alveolar pressure
would equilibrate with mouth pressure (Chowienczyk et al, 1991).
The pressure at the end of inspiration with airway closed, reflects the best estimate of peak alveolar pressure
, which is an important indicator of alveolar distension.