Thromboxane and prostacyclin release in adult respiratory distress syndrome

Plasma thromboxane B₂ (TXB₂) and 6-ketoprostaglandin F₁ (6-keto-PGF₁) were measured in 84 patients at risk of developing adult respiratory distress syndrome (ARDS) (44 patients following multiple trauma, 29 patients following abdominal surgery and 11 patients with acute pancreatitis). Forty-nine of these 84 patients developed an ARDS. High (>140 pg/ml plasma) TXB₂ values were found in 52/84 patients. The median values of TXB₂ were: 360 pg/ml in multiple injured, 250 pg/ml in abdominal surgery and 410 pg/ml in acute pancreatitis patients. The median TXB₂ value was 575 pg/ml in patients developing ARDS and 140 pg/ml in those without this complication: this difference was statistically significant (p<0.05). The median values of 6-keto-PGF₁ were 55pg/ml in multiple injured, 25 pg/ml in abdominal surgery and 120 pg/ml in acute pancreatitis patients. The median 6-keto-PGF₁ value was 122 pg/ml in ARDS patients and 25 pg/ml in non-ARDS patients (statistically significant: p<0.05). High TXB₂ and 6-keto-PGF₁ values were particularly related to sepsis in abdominal surgery patients (p<0.05) and in multiple injured patients (p<0.01). No relation could be established between abnormal TXB₂ or 6-keto-PGF₁ values and death. High TXB₂ values often persisted for several days and were observed particularly at the time ARDS diagnostic criteria were fulfilled. An imbalance between TXB₂ and 6-keto-PGF₁ was observed: 6-keto-PGF₁ values were always lower than TXB₂ values and did not persist for more than 24 h except in four cases. Our data demonstrate a significant production of prostanoids in ARDS patients particularly in sepsis and indicate a disturbance in balance of the prostacyclin/thromboxane axis.