Postobstructive pulmonary edema is a rare form of pulmonary edema that is caused due to obstruction in the upper airway. There are many views regarding the formation of postobstructive pulmonary edema. There are various supporters of the theory that states that postobstructive pulmonary edema occurs when there is a change in the intrathoracic pressure.
According to this theory when there is negative thoracic pressure in the lungs the patient will make an effort to inspire against the obstruction present in the airway. As a result of this there is considerable increase in the pulmonary venous capillaries. This leads to the postobstructive pulmonary edema.
In contrary to this theory, many clinicians believe that there is an increase in the permeability of pulmonary capillaries that is caused by damage of the alveolar epithelial lining and the pulmonary microvascular membranes. This may be caused due to exertion from mechanical stress that causes postobstructive pulmonary edema. Conclusively it has been found that various hydrostatic forces are the primary cause of postobstructive edema as in case of acute post obstructive form of pulmonary edema it was found that the epithelial lining of the alveoli was intact. This condition requires immediate medical attention along with artificial supply of oxygen.