To investigate the dynamic changes in the fibrinolytic system during and after open heart surgery performed with cardiopulmonary bypass (CPB) and the effect of epsilon-aminocaproic acid (EACA) on fibrinolysis,postoperative blood loss and transfusion requirements.Methods Forty patients (24 males,16 females )aged 17~43 yr undergoing valve replacement with CPB were randomized to receive EACA 200 mg·kg -1 (group A) or normal saline (group B) added to the priming solution.The patients were premedicated with intramuscular morphine 0.2 mg·kg -1 and scopolamine 0.3 mg.Anesthesia was induced with midazolam 0.2 mg·kg,fetanyl 10 μg·kg -1 and vecuronium 0.1 mg·kg -1 and maintained with isoflurane inhalation and intermittent i.v. boluses of fentanyl and vecuroniu.The patients were mechanically ventilated (VT=10 mg·kg -1 ,RR=10~12 bpm,I∶E=1∶2) after tracheal intubation.Blood samples were taken before skin incision (baseline),8 and 30 min on CPB,10 min after protamine administration and 2 h after operation for determination of tissue type plasminogen activator (t-PA) activity,plasminogen activator inhibitor (PAI) activity,plasmin (Plm) activity and D-dimer.The amount of blood drained from chest-and bank blood infused within 24 h after operation were recorded.Results (1) Group B (control group):PAI activity was maintained stable perioperatively.The t-PA activity and t-PA/PAI ratio increased significantly during operation but returned to the baseline value 2 h after operation.D-dimer level also significantly increased during and after operation.The Plm activity increased significantly at 8 h on CPB and 10 min after protamine administration compared to the baseline value.(2) The t-PA activity and t-PA/PAI ratio were significantly lower in group A than in group B.The D-dimer lever and Plm activity were also significantly lower in group A than in group B during and after operation.The amount of blood loss and bank blood infused within 24 h after operation was 40% and 37% less than that in group B.Conclusion Fibrinolytic system is activated during CPB as shown by the increase in plasminogen and t-PA/PAI ratio.EACA in effective in reducing postoperative blood loss and blood transfusion through inhibition of the activation of fibrinolytic system.8 refs,2 tabs.
展开▼
机译:Appropriate choice of stress modality in patients undergoing myocardial perfusion scintigraphy with a cardiac camera equipped with solid-state detectors: the role of diabetes mellitus