Prognostic value of eicosanoids in the acute respiratory distress syndrome

BACKGROUND: There is a great number of agents involved in the acute respira tory distress syndrome (ARDS) physiopathology, and some of them may have a prognostic value, The objective of the present study has been to analyse th e prognostic value of eicosanoids in this syndrome. MATERIAL AND METHOD: A prospective study with 21 consecutive ARDS patients admitted to the intensive care unit of a teraphy hospital in Barcelona, Spa in, was carried out. In the first 48 h of the ARDS diagnosis, at baseline, the plasma levels, (in peripheral arterial and pulmonary arterial samples) of thromboxane B-2 (TXB2), prostaglandin F1-alfa (PGF(1-alfa)) and leukotri ene B-4 (LTB4) were analysed by RIA, Simultaneously we measured different p ulmonary and systemic hemodynamical variables, as well as the pulmonary gas exchange data. We also studied the venous levels of the same eicosanoids i n 17 healthy adults, used as reference, RESULTS: Plasma levels of eicosanoids in the ARDS patients were higher than reference subjects (p < 0.05). No differences were observed between system ic arterial and pulmonary arterial values. From all the eicosanoids, only L TB4, (in both systemic arterial and pulmonary blood), was correlated with L IS (r = 0.49, p < 0.05; and r = 0.45, p < 0.05, respectively). Patients who did not survive presented a lower systemic-pulmonary arterial gradient of eicosanoids levels than survivors (-1.27 vs -0.10 ng/ml; p < 0.01). CONCLUSIONS: In our ARDS patients only LTB4 plasma levels correlated with t he severity of respiratory failure. Patients who did not survive presented a lower LTB4 gradient than survivors.