Abstract
We investigated right ventricular function after infusion of unwashed shed blood collected from mediastinal and chest tube drainage. Changes in thromboxane B 2 (TXB 2 ) and 6-keto-PGF 1α , which are stable metabolites of thromboxane A 2 (TXA 2 ) and prostacyclin respectively, were also investigated. The amount of infused shed blood was 484±76 ml (mean±SD). Right ventricular ejection fraction decreased rapidly after the infusion and did not return to its original level until 120 minutes later (P<0.05). Mean pulmonary artery pressure rose after infusion of the shed blood (P<0.05). The TXB 2 level in the unwashed shed blood was about 20,000 times higher than the preoperative plasma level. The plasma TXB 2 level at 30 minutes after the infusion was significantly elevated (P<0.05), and at 120 minutes it had returned to the original level. Unwashed shed blood may contain vasoactive substances that induce the release of TXA 2 and increase right ventricular afterload.