Plasma thromboxane concentrations are raised in patients dying with septic shock.

Central venous plasma concentrations of thromboxane B2 (TXB2) the stable metabolite of the vasoconstrictor platelet aggregator thromboxane A2, were measured in 12 patients with septic shock. In 8 patients dying with septic shock the concentration of plasma TXB2 (912 +/- 250 pg/ml) was ten times higher than that in 4 survivors of septic shock (92 +/- 25 pg/ml) and 6 controls (91 +/- 18 pg/ml). Prothrombin time and partial thromboplastin time were significantly prolonged in nonsurvivors compared with survivors. Similarly, the alveolar-arterial oxygen gradient was significantly raised in nonsurvivors (233 +/- 39 mm Hg) compared with survivors (112 +/- 47 mm Hg). This study demonstrates that the metabolism of arachidonic acid to thromboxanes is increased in patients dying of septic shock and this raises the possibility that thromboxanes may be involved in the disseminated intravascular coagulation and respiratory distress syndrome associated with severe sepsis.