Coagulation Flashcards
<p>Four components of Hemostasis</p>
<p>Vasoconstriction
<br></br>Platelet activation and aggregation
<br></br>Coagulation Cascade
<br></br>Fibrinolytic system</p>
<p>Coagulation cascade in hemostasis</p>
<p>TF + VIIa activate X
<br></br>X converts prothrombin (II) -> thrombin
<br></br>Thrombin activates platelet, VIII, V
<br></br>9a/8a generate large amount of thrombin via 10a/5a amplification
<br></br>Thrombin converts fibrinogen (I) to fibrin</p>
<p>PT measures involves which clotting factors?</p>
<p>2,5, 7, 10</p>
<p>APTT involves which clotting factors</p>
<p>8,9,11,12,vWF</p>
<p>Function of vitamin K</p>
<p>Carboxylates factor 2,5,7,10, allows them to bind to calcium and hence surface of platelets</p>
<p>Factors of the intrinsic pathway</p>
<p>8,9,11,12,vWF</p>
<p>Factors of the extrinsic pathway</p>
<p>7, 10</p>
<p>Process of fibrinolysis</p>
<p>Thrombin induce endothelial cell release of urokinase and tPA => convert plasminogen to plasmin
<br></br>Plasmin leads to fibrin break down into fibrin degradation products</p>
<p>Natural anticoagulants</p>
<p>Antithrombin III
<br></br>Protein C
<br></br>Protein S
<br></br>Plasmin</p>
<p>DIC</p>
<p>uncontrolled and excessive production of thrombin leading to widespread and systemic intravascular fibrin deposition</p>
<p>Biochemical picture in DIC</p>
<p>Prolonged INR, APTT,
<br></br>Thrombocytopenia
<br></br>Decrease fibrinogen
<br></br>Increase D-dimer</p>
<p>Treatment of DIC</p>
<p>Treat underlying cause<br></br>
| Supportive transfusion</p>
<p>Draw the coagulation pathway</p>
<p>Warfarin</p>
<p>Vitamin K antagonist</p>
<p>Reduced activity of Vitamin K dependent coagulants, namely procoagulant factors 2, 7, 9, 10 and anti-coagulant factors Protein C and S</p>
<p>Asprin</p>
<p>COX inhibitor</p>
<p>Irreversible</p>
<p>Platelet inhibition</p>
<p>Plavix</p>
<p>ADP receptor antagonist</p>
<p>LMWH</p>
<p>polymerized heparin</p>
<p>inactivates factor Xa</p>
<p>More predictable anticoagulant effect, longer half-life</p>
<p>Unfractionated heparin</p>
<p>Potentiated antithrombin III effects on inactivation of factors Xa, IIa (thrombin). Also factors IXa, XIa, XIIa</p>
<p>Massive blood transfusion</p>
<p>Defined as replacement of a patient’s entire circulating blood volume within a 24 hr period</p>
<p>or half the blood volume in 3 hr or by a rate of loss of 150 ml/min</p>
<p>Complications of massive blood tranfusion</p>
<p>Hypothermia</p>
<p>Electrolyte disturbance (HyperK, HypoCa, HypoMg)</p>
<p>Volume overload</p>
<p>Acid-base disturbance</p>
<p>Dilutional coagulopathy (coagulation factor deficiency, thromobocytopenia)</p>
<p>Metabolic acidosis (lactic acid and citrate)</p>
<p>Four factors contributing to coagulopathy in major trauma</p>
<p>Hemodilution</p>
<p>Consumption of clotting factors</p>
<p>Hypothermia (plt dysfunction)</p>
<p>Acidosis</p>
<p>Massive blood transfusion protocol</p>
<p>Transfusion of blood products in 1:1:1 ratio</p>
<p>How to evaluate when mechanical ventilation can be weaned off?</p>
<p>Arousable</p>
<p>Hemodynamically stable</p>
<p>No new potentially serious conditions</p>
<p>Low ventilatory and end-expiratory pressure requirements</p>
<p>Low Fio2 requirements which can be met safely delivered with a face mask or nasal cannula.</p>
<p>Successful spontaneous breathing trial</p>
<p>Ventilator care bundle to reduce VAP</p>
<p>Maintaining the bed at 30°–45° head–up</p>
<p>Oral decontamination with chlorhexidine and regular mouth care</p>
<p>Maintaining tracheal cuff pressures of 20–30 cmH2O</p>
<p>Daily sedation hold</p>
<p>DVT and stress ulcer prophylaxis</p>
<p>Subglottic aspiration</p>
