Adult respiratory distress syndrome in postoperative patients: study of pulmonary pathology in "shock lung" with prophylactic and therapeutic implications.

Lungs of 44 patients who died after postoperative respiratory distress and shock had a significantly higher incidence of atelectasis and thromboembolism than did 31 control patients. However, both lesions were as inconstant in occurrence as all other 15 investigated pulmonary changes. Moreover, no clear correlation between lung pathology and duration of shock was found and the incidence of thromboembolism was too low (one clot for each 16 or more counted vessels) to generate any significant vascular obstruction. Furthermore, pulmonary pathology in patients with postoperative respiratory distress was independent of the presence or absence of shock and some of the most typical findings of "shock lung" were more often present in patients who did not have shock but died of aspiration pneumonia. While possibly a contributing factor, shock is not the most important cause of the pulmonary lesions in postoperative patients. The term "shock lung" should be eliminated and renewed emphasis should be placed on detection, prevention and treatment of the pathogenic mechanisms involved in each individual case.