The clinical usefulness of quantitative plasma polymorphonuclear elast
ase (PMN-elastase) determinations as prognostic markers of adult respi
ratory distress syndrome (ARDS) in polytraumatized patients was analyz
ed. PMN-elastase and C-reactive protein (CRP) levels were determined i
n 55 polytraumatized patients admitted into the Intensive Care Unit. E
ight patients developed ARDS and 47 patients did not. These parameters
were also analyzed in a control group (n = 34). PMN-elastase levels i
n ARDS cases reached significantly higher values than in patients who
did not develop this syndrome (P < 0.01). We conclude that the increas
e in plasma PMN-elastase levels can be useful in predicting the develo
pment of ARDS in polytraumatized patients, in instituting prophylactic
actions and monitoring the course of the disease in these high risk p
atients. This test is easily adaptable to the routine of any hospital
laboratory.