Disorders of Hemostasis PDF

Disorders of Hemostasis NRAN 80413 Casey Crow DNP, CRNA Overview Disseminated Intravascular Coagulation (DIC) von Willebrand Disease Hemophilia Sickle cell anemia Massive blood transfusion Thrombotic disorders Objectives Describe the different coagulopathies: DIC, AvWS, vWD, Hemophilia A, Hemophilia...

Disorders of Hemostasis NRAN 80413 Casey Crow DNP, CRNA Overview Disseminated Intravascular Coagulation (DIC) von Willebrand Disease Hemophilia Sickle cell anemia Massive blood transfusion Thrombotic disorders Objectives Describe the different coagulopathies: DIC, AvWS, vWD, Hemophilia A, Hemophilia B, SCD Describe the management of the different coagulopathies: DIC, AvWS, vWD, Hemophilia A, Hemophilia B, SCD Describe MBT and MTP Identify complications regarding MTP Describe banked-blood issues Describe the different thrombotic disorders: Protein C deficiency, Protein S deficiency, Factor V Leiden Mutation Disseminated Intravascular Coagulation Definition: “A result of intravascular coagulation activation with microvascular thrombi formation, which causes thrombocytopenia and clotting factor depletion, leading to bleeding and end-organ complications” Nagelhout Acquired disorder Simultaneous occurrence of hemorrhage and systemic thrombosis due to: Disorganized clotting Disorganized fibrinolysis Diagnosis is usually secondary to an underlying pathologic process DIC Generalized thrombin formation creates microvascular clots Impaired tissue perfusion Tissue hypoxia and acidosis Systemic activation of coagulation Intravascular deposition of fibrin Thrombotic microangiopathy Compromised blood supply to organs Multiorgan system failure Body attempts to break down clots Activates anticoagulant system Widespread consumption of coagulation factors, fibrinogen and platelets Induce bleeding from multiple sites DIC DIC DIC Mild Thrombocytopenia Prolongation of clotting times Acute DIC Extensive thrombosis Extensive bleeding Pathogenesis of DIC Normal physiology: antithrombin (ATIII) and tissue factor pathway inhibitor (TFPI) keep procoagulants regulated DIC: TF (factor III) is released in the absence of vascular injury Activation of extrinsic pathway Hyperthrombinemia Pathogenesis of DIC Clots in microvasculature Impaired tissue perfusion Tissue necrosis End-stage organ failure Widespread fibrin deposition Consumes body’s fibrinogen, coagulation factors and platelets supply Hemorrhage Release of tPA and urokinase-type plasminogen activator Increased D-Dimer Due to increased fibrinolytic activity Clots are forming and broken down simultaneously Etiology of DIC Signs of DIC Acute/Overt Develops quickly over hours/days Ecchymosis Petechiae Mucosal bleeding Bleeding at IV and puncture sites Prolonged PT and PTT Increased D-Dimer and FDP Decreased fibrinogen and antithrombin Chronic/Nonovert Develops slowly over weeks/months Not recognized as quickly Subtle, hemostatic dysfunction Has not yet reached decompensation stage Diagnosis of DIC Clinical presentation Signs and symptoms previously listed Lab tests Platelet count Thrombocytopenia aPTT, PT Fibrin related markers: FDPs and D-Dimer Fibrinogen Antithrombin International Society of Thrombosis and Hemostasis Scoring System for DIC Distinguishes between overt and nonovert International Society of Thrombosis and Hemostasis Scoring System for DIC Score >5: Acute/overt DIC Score FFP Sickle Cell Trait Heterozygous disorder: 10% of African-American population Hgb S levels: 30-50% Sickling observed at PaO2 of 20-30 mmHg Generally, those with trait do not advance to crisis Exception: Severe hypoxemia Sickle Cell Disease Homozygous disorder: 0.51% of African-American population Amino acid substitution: valine substituted for glutamic acid on beta globulin chain Altered RBC geometry and RBC function Sickling observed at PaO2 of 30-40 mmHg RBC Function in SCD Deoxygenation of Hgb S Leads to sickling Sickling causes RBCs to clump Mechanical obstruction in microvasculature of vital organs and joints Tissue perfusion impairment Intense pain Especially in bones/joints Sickled cells prone to hemolysis and removal by spleen Lifespan cut to 12-17 days (normal RBC lifespan 120 days) Anesthetic Management SCD Avoid conditions/triggers that promote sickling Pain Hypothermia Hypoxemia Acidosis Dehydration SCD Complications Vaso-occlusive crisis Most common manifestation of SCD Sickled cells, impaired tissue perfusion, ischemic injury Treatment: analgesics, hydration Hydroxyurea: reduces incidence and severity Sequestration crisis Spleen removes RBCs from circulation at a faster rate than bone marrow produces them Anemia, hemodynamic instability Acute chest syndrome Significant sources of mortality (1-20%) Caused by thrombosis, embolism, infection More common in children Diagnosis: lung infiltrates on CXR and at least 1 of the following: CP, cough, dyspnea, wheezing Common postoperatively Causes: hypoventilation, narcotics, splinting, pain SCD Complications Aplastic crisis RBCs with HgbS have short half-life Small amount of bone marrow suppression can cause anemia Caused by viral infection (parvovirus B19) Pneumococcal disease Children are highest risk Prophylaxis: pneumococcal vaccination and daily PCN (up to 5 years old) Others Asthma, 50% of patients Pulmonary HTN in 10% of patients SCD Medical Treatment Stop sickling, ischemia, infarction, pain and end-organ failure Rest Prevention/treatment of infections Normothermia Analgesia: consider Hydration regional analgesia Oxygen therapy Transfusion to reduce the Incentive Spirometry Hgb S disease Hyperbaric oxygen therapy concentrations SCD Preop Considerations Preop hydration Initiate early, treat baseline volume deficit Normothermia maintenance Begin preop warming Treat infections End-organ dysfunction identification and treatment Consider transfusion of RBCs to maintain O2 carrying capacity High-risk patients, decrease Hgb S to at least 10-11 g/dL Avoid hypoxemia Maintain normothermia Maintain normal acid-base status Adequate perioperative pain management SCD Intraop Considerations Prevent venous stasis Hydration Adequate perioperative pain management Only use tourniquet when absolutely necessary, short duration Maintain adequate oxygenation and prevent respiratory and metabolic acidosis with tourniquet deflation SCD Postop Considerations Early mobilization Normothermia Supplemental oxygen Early, effective analgesia Adjunctive analgesia Euvolemia Incentive spirometry Pulmonary monitoring Psychological support Extended postop monitoring: BP, EKG, SpO2 Regional analgesia for postop pain management Massive Blood Transfusion (MBT) Hemorrhage Leading cause of preventable death after trauma Accounts for up to 50% of deaths within first 24 hours after injury Early and rapid delivery of blood products with primary goal of treating acute coagulopathy has improved mortality MBT and Massive Transfusion Protocol (MTP) Massive blood transfusion Replacement of entire blood volume within 24 hours Transfusion >10 units PRBCs in 24 hours Transfusion >5 units PRBCs in 1 hour Ongoing need is foreseeable Massive transfusion protocols Goal: establish a process for coordinated and timely delivery of blood products and adjunctive therapies throughout the hospital Response to blood product delays and concerns of improper administration during massive transfusion Trauma and MTP Implementation of MTP most associated with trauma Forward military medical units and trauma EDs have developed MTP Key element: plan/algorithm to communicate with blood bank and trauma team MTP MTP Interrupt lethal triad: Acidosis, hypothermia, coagulopathy Focus: Fluid resuscitation for volume expansion, RBC transfusion to maintain tissue oxygenation Strategies to obtain massive amounts of allogenic blood and blood products Assists interactions of medical team and blood bank Judicious use of blood and blood components May be activated after transfusion of 4-10 units PRBCs MTP FFP: early administration decreases coagulopathy and improves survival FFP provides factors V, VIII, and fibrinogen MTP have predefined ratio RBCs:FFPs/platelets or cryoprecipitate Not a standardization- varies by institution Transfusion Indications Hemorrhagic shock Ongoing hemorrhage Anemia Goal of transfusion is restoration of the oxygen-carrying capacity, NOT restoration to a specific Hgb level Transfusion Perioperative Several factors to consider Comorbidities Anticipated loss Hemodynamic stability Not recommended when Hgb ≥10 g/dL Hgb 100 mg/dL Hgb 7-9 g/dL Reference: Hess, John R. (2023). Massive Blood Transfusion. UpToDate Substitution note: 1 g Calcium Chloride is equivalent to 3 g Calcium Gluconate Point-of-care testing Thromboelastography (TEG) Test of visco-elastic properties of blood Examine entire hemostatic system Platelet function and fibrinolytic system Useful in coagulopathies Rapid availability Timely interventions Coagulation tests Long processing times May not be helpful in guiding therapy in rapidly evolving blood loss Targets of Resuscitation MAP: 60 mmHg (higher in HTN patients) Hgb: 7-9 g/dL INR < 1.5 aPTT < 42 sec Fibrinogen > 1.5-2 g/L Platelets > 50x109 /L pH 7.35-7.45 Core temp > 35 degrees C Base deficit > final common pathway Mutation of factor V Resistance to anticoagulant effect on protein C Women: increased tendency for blood clots during pregnancy or when taking estrogen Treatment Anticoagulation for those with thromboembolism Lifelong anticoagulation is not warranted unless recurrent thrombotic events Review Questions What is the definition and pathogenesis of DIC? Why is the etiology of DIC important for diagnosis and treatment? Identify common etiologies and treatment. What are the vWD types and how are they distinguished? What are the expected lab findings in AvWS and vWD? What is the typical treatment for vWD disease? What are the types of Hemophilia and which coagulation factors are deficient? What are the expected lab findings in Hemophilia? What is the perioperative management of Hemophilia? What is the difference between sickle cell trait and sickle cell disease? What is the effect of PaO2? What is the anesthetic management of SCD? What should be avoided in a patient with SCD? What is the definition of MBT? What is the goal of transfusion protocols? What blood products are involved during MTP? What is the importance of the different blood products? What are the 4 classes of hemorrhage? What is the ABC Score? What are the issues of stored blood? What are the targets of resuscitation when performing MTP? What are the thrombotic disorders? References Motamenji, A., Hodge, R., McKinely, W., Georgel. (2018). The use of ABC score in activation of massive transfusion: the yin and the yang. Journal of Trauma and Acute Care Surgery, 85(2), 298–302. Nagelhout,J., & Elisha, S. (2017). Nurse Anesthesia, 6th Ed., Elsevier Saunders, Philadelphia, PA. Chapter 38 Patil & Shetmahajan (2014). Massive transfusion and massive transfusion protocol. Indian Journal of Anaesthesia, 58(5), 590 – 595. Retrieved from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4260305/ Sundd, P., Gladwin, M.T., & Novelli, E.M. (2019). Pathophysiology of sickle cell disease. Annual Review of Pathology: Mechanisms of Disease, 14, 263–292. Widmaier, E.P., Raff, H., & Strang, K. T. (2015). Vander’s Human Physiology, 14th ed. Chapter 12, Section F