Coagulation and Anesthesia

T/F. Platelets require an ABO match.

False! **platelets are ABO preferred! FFP must be ABO compatible. "Platelets are preferred and FFP must be!"

T/F. Your patient took aspirin despite being told to stop antiplatelet therapy 7-10 days prior to their surgery. The surgeon decides it is fine to proceed because ASA is reversible.

False. **Aspirin is a cyclooxygenase inhibitor. It IRREVERSIBLY inhibits cyclooxygenase for 7-10 days. NSAIDS are REVERSIBLE and inhibit the cyclooxygenase pathway for 24-48 hours.

T/F. Platelets have a nucleus that comprises DNA.

False. **Platelets (thrombocytes) have a life span of 8-12 days. Normal range is 150,000-400,000 cells/ml. They form in bone marrow and 33% are sequestered in the spleen. They have NO NUCLEUS (no DNA), cannot reproduce, and are 1/2 the size of RBCs.

DIC Stage 1: Hypercoagulable state with secondary fibrinolysis

Identify this TEG result

Normal

Identify this TEG result

Primary Fibrinolysis

Identify this TEG result

TEG measure the process of clot formation, consolidation & lysis, and involves all elements of the hemostatic process. R = time until fibrin formation (factor dependent) K = clot strength (fibrinogen dependent) alpha = rate of clot formation MA = max amplitude or clot strength & stability CLT = clot lysis time

Identify this TEG result

T/F. Factors in the Final Common Pathway include factors I, II, V, and X and XIII.

True!

T/F. The ACT for bypass should be > 400 - 450

True!

T/F. Hemoglobin is a protein in the cell that is responsible for carrying oxygen.

True! ** 1 cc/kg RBCs will increase HCT by 1%, I unit PRBCs will increase hct by 3%.

T/F. A platelet count of 10,000-20,000/ml may result in spontaneous bleeding.

True! **Platelet counts are quantitative and do not reflect platelet activity. plt < 150,000 = thrombocytopenia. plt count of 40,000-70,000 may result in severe bleeding during surgery.

T/F. Secondary hemostasis results in the conversion of fibrinogen --> fibrin.

True! ** Secondary hemostasis is the production of fibrin. This is when the stable clot (red clot) is formed. It involves the intrinsic, extrinsic, and final common pathways.

T/F. Heparin works on the intrinsic and final common pathway.

True.

What is the normal clot formation time for PT (prothrombin time) testing? a) 12-14 sec b) 25-35 sec c) 60 sec d) WTF

a) 12-14 sec **PT examines extrinsic and final common pathway. INR is a standardized reagent used for monitoring oral anticoagluant therapy (coumadin). PTT = 25-35 sec TT = <30 sec Fibrinogen = >150 mg/dL ACT = 90-140 sec (CPB = 400-450)

APEX Q: Select the BEST tx for a prolonged R time on the TEG a) FFP b) cryo c) desmopressin d) TXA

a) FFP ** R time measures time to begin forming clot. Prolonged R time reflects problem with coag factors and best tx is FFP.

This type of heparin induced thrombocytopenia (HIT) is a more mild, self-limiting form. The onset is 1-2 (4) days and plt count stays > 100,000. No treatment is necessary. a) HIT type 1 b) HIT type 2 c) HIT A d) HIT B

a) HIT type 1 **HIT type 2 = immunoglobulin-G mediated. Mortality is 20-30%, onset is 5-10 days. Plt count <100,000. Stop heparin, check plt factor 4 antibodies, and a serotonin release assay.

Which factor is NOT vitamin K dependent? a) I b) II c) VII d) IX e) X

a) I (fibrinogen)

Which 2 factors are in the extrinsic pathway? a) VII b) III c) II d) XI

a) VII b) III

The intrinsic pathway contains all of the following clotting factors EXCEPT: a) VII b) VIII c) IX d) XI e) XII

a) VII **The intrinsic pathway is triggered by damage from within the vessel and exposure to collagen. XII and platelets come into contact with collagen initiating the intrinsic pathway. Clotting occurs by both intrinsic and extrinsic pathways simultaneously, NOT as two seperate pathways converging as the final common pathway.

Which two medications will stop the breakdown of a clot by inhibiting plasmin (antifibrinolytic)? a) amicar b) tPA c) tranexamic acid d) coumadin

a) amicar c) tranexamic acid ** Amicar and tranexamic acid (TXA) STOP the breakdown of clot by inhibiting plasmin--> anti-fibrinolytic. Amicar can be associated with temporary renal dysfunction. TXA has also been known to lead to seizures at higher doses.

What type of drug is abciximab (ReoPro)? a) glycoprotein IIb/IIIa inhibitor b) cyclooxygenase inhibitor c) thienopyridine derivative d) thrombolytic

a) glycoprotein IIb/IIIa inhibitor **This medication is a POTENT inhibitor of platelet aggregation (antiplatelet drug). It will block the binding of fibrinogen and vWF to platelets. It should be d/c'd 24 hours prior to surgery.

APEX Q: Which condition places a patient at the GREATEST risk of developing DIC? a) gram-negative sepsis b) adenocarcinoma c) preeclampsia d) placental abruption

a) gram-negative sepsis **All predispose but gram-negative carries the highest risk

APEX Q: Which anesthetic modalities reduce the incidence of morbidity in pts with sickle cell disease? a) hydromorphone b) permissive hypercapnia c) fluid restriction d) forced-air warmer

a) hydromorphone d) forced-air warmer

Matching: Match the steps to the stage of hemostasis a) primary hemostasis b) secondary hemostasis c) final process 1) fibrin clot 2) fibrinolysis 3) platelet plug

a) primary hemostasis + 3) platelet plug (white clot) b) secondary hemostasis + 1) fibrin clot (red clot) c) final process + 2) fibrinolysis **Fibrin is the hallmark of secondary hemostasis

Which of the following terms BEST describes von Willebrand factor (vWF) ? a) procoagulant b) anticoagulant c) fibrinolytic d) antifibrinolytic

a) procoagulant

APEX Q A deficiency in which mediators favors hypercoagulability (select 2): a) protein S b) fibronectin c) alpha-antiplasmin d) antithrombin

a) protein S d) antithrombin

Which two are known as plasminogen activators that circulate in the intact vascular endothelium? a) tPA b) ADP c) urokinase d) tenase

a) tPA c) urokinase **These will catalyze the activity of plasminogen on plasmin. Under normal conditions this is released VERY slowly.

Match each factor with it's primary function in the blood: a) von Willebrand factor b) Protein C c) Plasminogen activation inhibitor d) tPA 1) procoagulant 2) anticoagulant 3) Fibrinolytic 4) Antifibrinolytic

a) von Willebrand factor + 1) procoagulant = causes clotting b) Protein C + 2) anticoagulant = hinders clot formation c) Plasminogen activation inhibitor + 4) antifibrinolytic = impairs the clot break down process d) tPA + 3) fibrinolytic = breaks down clots

How much of the thrombocytes are sequestered in the spleen? a) 20% b) 33% c) 50% d) 75%

b) 33% **The thrombocytes are formed in the bone marrow and are held in the spleen waiting to be used.

APEX Q: Severe liver failure will reduce the synthesis of which coagulation factors (select 2): a) 4 b) 8 c) 3 d) 1

b) 8 d) 1 **The liver synthesizes all coag factors except 3 (tissue factor) and 4 (calcium).

Clotting of donated blood is prevented by reducing what ions? a) Na+ b) Ca+ c) K+ d) Mg+

b) Ca+ This is done by deionizing with citrate ions and precipitating with oxalate ions.

What is the FIRST LINE treatment for von Willebrand's disease? a) vasopressin b) DDAVP c) factor VIII d) emicizumab

b) DDAVP **DDAVP = 1deamino-8 d-arginine vasopressin. DDAVP will trigger the release of endogenous vWF. Cryoprecipitate and recombinant VIII vWF (humate P) concentrate are also treatment options for patients with von Willebrand's disease.

A patient arrives to the hospital and requires emergent surgery. Upon review, you find the patient has been taking coumadin and a preop INR reveals the patients level is >3. What should you give to reverse the effects of this patients coumadin? a) VIT K (phytonadione) b) FFP c) Prothrombin complex concentrates (PCCs) d) Kcentra

b) FFP **FFP: 10-15 ml/kg IV; Used for the emergent reversal of INR > 1.5 (dt coumadin therapy). VIT K is not an immediate reversal of INR and can be given orally or IV.

Which factors are NOT synthesized in the liver (select all that apply): a) II b) III c) IV d) VIII vWF e) IX f) X g) XIII

b) III c) IV d) VIII vWF **3 = tissue (vascular wall and extravascular cell membranes; 4 = diet; 8 vWF = vascular endothelial cells

What type of drug is coumadin? a) procoagulant b) anticoagulant c) fibrinolytic d) antifibrinolytic

b) anticoagulant **Coumadin is a VIT K antagonist. It binds competitively to VIT K receptors found in the liver, leading to a decreased production in VIT K dependent factors (II, VII, IX, X, protein C and protein S)

Which pathway does coumadin work on? a) intrinsic b) extrinsic c) final common d) none of the above

b) extrinsic pathway **Extrinsic pathway is stimulated from damage outside of the blood vessel. We would check a PT/INR to monitor the effects of coumadin.

Which disease process is considered a sex-linked blood disorder (select 2)? a) von Willebrand's disease b) hemophilia A c) hemophilia B d) heparin induced thrombocytopenia

b) hemophilia A c) hemophilia B **Hemophilia is an X linked, recessive bleeding disorder with deficiency in factor VIIIc (in type A). Type B is factor IX deficiency and is less common. Almost exclusively males and occurs in 1:10,000 (females can be carriers). You will see a prolonged PTT and normal PT.

ATIII deficiency is manifested as what? a) heparin acceptance b) heparin resistance c) von Willebrand's disease d) liver disease

b) heparin resistance ** ATIII deficiency is manifested as heparin resistance. ATIII deficiencies are seen in patients with cirrhosis and nephrotic syndrome. This can be treated with FFP.

Identify the BEST predictor of bleeding during surgery? a) PT/INR b) history and physical c) thromboelastogram d) bleeding time

b) history and physical **History and physical is the best predictor of bleeding during surgery (this is direct APEX question)

APEX Which mediator causes vasoconstriction after vascular injury? a) prostacyclin b) thromboxane A2 c) NO d) vWF

b) thromboxane A2

APEX Q Matching a) antithrombin III b) vWF c) plasminogen d) alpha-antiplasmin 1) fibrinolytic 2) procoagulant 3) antifibrinolytic 4) anticoagulant

b) vWF + 2) procoagulant a) antithrombin III + 4) anticoagulant c) plasminogen + 1) fibrinolytic d) alpha-antiplasmin + 3) antifibrinolytic

Which of the following is the MOST common inherited bleeding disorder? a) hemophilia A b) von Willebrand's disease c) hemophilia B d) Vitamin K deficiency

b) von Willebrand's disease **vWF is manufactured and released from endothelial cells. It is normally stored in plts and plasma, and t's primary role is to mediate platelet adhesion. Men are at higher risk.

For patients with a history of sickle cell anemia, at what PaO2 will cells begin to sickle? a) 40-60 mmHg b) 40-50 mmHg c) 30-40 mmHg d) 10-20 mmHg

c) 30-40 mmHg ** Sickle crisis marked by hemolytic anemia is precipitated by hypoxemia, hypothermia, infection, dehydration, stasis, and acidosis.

How long should aspirin be stopped prior to an interventional pain procedure? a) 2 weeks b) 48 hours c) 4-6 days d) 10-14 days

c) 4-6 days **Low risk of spinal hematomas d/t continued formation of new/fuctional plts. ASA must be stopped for 4-6 days prior to procedure.

Clopidogrel is a thienopyridine/antiplatelet that prevents plt aggregation, inhibits ADP mediated plt activation. How many days should this medication be held prior to a neuraxial procedure? a) 10-14 days b) 5 days c) 7 days d) 6-24 hours

c) 7 days **Antiplatelet drugs can be restarted 6-24 hours after a neuraxial procedure or cathetar removal (24 hours is preferred).

APEX Q: A septic patient undergoing exploratory laparotomy has developed bleeding from the wound and around his IV sites. He has a platelet count of 40,000, fibrinogen of 95 mg/dL, and an elevated D-dimer. What is the BEST treatment for this patient? a) heparin infusion b) tranexamic acid c) FFP d) albumin

c) FFP ** DIC is characterized by disorganized clotting and fibrinolysis that lead to the simultaneous occurrence and systemic thrombosis. Tx of DIC is reversal of the cause, which in this case is sepsis

Which coagulation factor is responsible for converting fibrinogen to fibrin? a) Factor IX b) Tissue factor c) Thrombin d) prothrombin

c) Thrombin (IIA) ** The conversion of fibrinogen to fibrin occurs during secondary hemostasis. Thrombin acts as an enzyme to convert fibrinogen (I) to fibrin (IA) fibers which enmeshes platelets, blood cells, and plasma, crosslinking and forming a clot with the help of XIII ----> stable (red) clot

Which of the following clotting factors have the shortest half life? a) II b) III c) VII d) IX

c) VII ** Proconvertin has a half life of 4-6 hours

During primary hemostasis, which factor leads to platelet adhesion? a) fibrin b) thrombin c) VIII: vWF d) VII

c) VIII: vWF **von Willebrand factor is synthesized and released by endothelial cells. vWF promotes platelet adhesion to the sub endothelial layer and cause the platelets to adhere.

Which of the following direct thrombin inhibitors is the best anticoagulant for PCI/CPB? a) argatroban b) hirudin c) bivalirudin d) dabigatran

c) bivalirudin **Bivalirudin (angiomax) is the anticoagulant of choice for PCI/CPB. Argatroban is also used with HIT- but should be used with caution in patients with liver disease d/t hepatic elimination.

APEX Q Which laboratory test measures the extent of fibrin breakdown? a) TT b) bleeding time c) d-dimer d) antithrombin assay

c) d-dimer

APEX Q: Rapid admin of DDAVP will MOST likely cause: a) hyperglycemia b) bronchospasm c) hypotension d) thrombosis

c) hypotension

APEX Q: Triggers of sickle cell crisis include: a) alkalosis b) hyperthermia c) pain d) dehydration

c) pain d) dehydration **Pain, dehydration, hypoxemia, acidosis, hypothermia

HIT is a disorder associated with which of the following blood components: a) plasma b) erythrocytes c) platelets d) neutrophils

c) platelets **HIT is a platelet disorder resulting from a immunologic complication of heparin therapy. It results in heparin resistance, thrombocytopenia, and a positive HIT assay. Treatment includes a direct thrombin inhibitor such as argatroban or hirudin.

Which step is the FIRST step in the final common pathway process? a) VIIa combines with IV and TF b) factor XIa combnies with VIII c) prothrombin activates thrombin d) who the hell cares

c) prothrombin activates thrombin **Prothrombin (II) is converted to thrombin (IIa) on the platelet cell surface, after complexing with Xa, Va, & Ca+. Ca+ helps factors adhere and react on the platelet surface. Thrombin (IIa) converts fibrinogen (I) --> fibrin (Ia) with the cross linking of XIII a stable clot is formed.

Your patient is scheduled for a major surgery and has von Willebrand's disease type III. What medication would be most appropriate to give to this patient preoperatively? a) DDAVP b) cryoprecipitate c) recombinant VIII vWF d) FFP

c) recombinant VIII vWF ** Type III vWD is rare and vWF is ABSENT. These patients can have severe bleeding into joints and muscles. Recombinant VIII vWF (humate P) concenrate should be administered pre operatively and intraoperatively for these patients. Cryoprecipitate contains factors VIII, I (fibrinogen), and XIII.

What type of drug is clopidogrel (Plavix)? a) glycoprotein IIb/IIIa inhibitor b) cyclooxygenase inhibitor c) thienopyridine derivative d) thrombolytic

c) thienopyridine derivative ** This medication interferes with fibrinogen binding to platelets, inhibiting ADP and therefore both primary and secondary platelet aggregation. It is an ADP antagonist that affects platelets for 7 days.

Which of the following factors are inhibited when patients are taking coumadin? a) 3 and 10 b) 2, 7, 9, and 10 c) 2, 7, 9, 10 and protein C d) 2, 7, 9, 10, protein C and protein S

d) 2, 7, 9, 10, protein C and protein S ** Warfarin is a vitamin K antagonist and it inhibits the production of vitamin K dependent factors (2, 7, 9, and 10). It also inhibits proteins C and S (APEX)

How long must a provider wait to do a spinal after patient receives enoxaparin? a) 12 hours b) 6 hours c) 18 hours d) 24 hours

d) 24 hours

What can be administered to a patient with an ATIII deficiency? a) platelets b) cryoprecipitate c) VIT K d) FFP

d) FFP ** Heparin resistance can be due to a decrease in endogenous ATIII or excessive VIII & I- give FFP to ATIII. FFP does not contain platelets (forgot freaking platelets)

What test do we utilize in order to monitor the effects of heparin? a) PT/INR b) TT c) d-dimer d) PTT/ACT

d) PTT/ACT **Partial thromboplastin time (PTT) is measured in seconds. Normal is 25-35 seconds. Prolonged PTT would indicate decreased levels of VIII, IX, XI, XII. Heparin impacts the intrinsic pathway.

Unfractionated heparin (UFH) binds antithrombin, accelerates the ability to inactivate thrombin, Xa, IXa. For a patient undergoing a neuraxial procedure, which SQ dosing is NOT recommended? a) BID b) daily c) Q12H d) TID

d) TID ** NOT recommended in patients receiving TID dosing. Avoid neuraxial procedures within 2 hours of UFH and ensure PTT is <40. Removal 2-4 hours after last heparin dose.

Which substance is responsible for adhering the platelet to the damaged vessel? a) thromboxane A2 b) ADP c) tissue factor d) Von Willebrand factor

d) Von Willebrand factor **You should associate platelet adhesion with von Willebrand factor. ADP and thromboxane A2 should be associated with platelet activation and aggregation.

You're administering heparin and your CRNA asks you what coagulation pathways does this medication work on. You answer: a) intrinsic pathway b) extrinsic pathway c) final common pathway d) a & c e) panic and say "I don't know"

d) a & c

Protamine is a specific antagonist for heparin. Its adverse reactions include which of the following? a) hypertension b) bradycardia c) decrease PVR d) allergic reaction

d) allergic reaction ** Adverse reactions to protamine include: hypotension-histamine release, flushing, tachycardia, hypotension, pulmonary hypertension-thromboxane and 5hydroxyl tryptamine (serotonin), pulmonary vasoconstriction, pulmonary hypertension, bronchoconstriction, hypoxemia, pulmonary edema, and histamine release. Patients on NPH insulin and with a history of vasectomy are at an increased risk for an allergic reaction.

Plasminogen activator inhibitor (TXA/amicar) greatly limits fibrinolytic activity- making this medication: a) a procoagulant b) an anticoagulant c) a fibrinolytic d) an antifibrinolytic

d) an antifibrinolytic

APEX Q: A patient with a history of type 2 heparin-induced thrombocytopenia requires anticoagulation for CPB. What is the BEST treatment?? a) enoxaparin b) heparin test dose c) warfarin d) bivalirudin\argatroban

d) bivalirudin\argatroban **Bivalirudin is a direct thrombin inhibitor that's an alternative to heparin, and is suitable alternative for anticoaglylation during CPB.

Heparin inhibits the: a) extrinsic pathway b) intrinsic pathway c) extrinsic and final common pathway d) intrinsic and final common pathway

d) intrinsic and final common pathway (APEX)

APEX Q: Patients who are deficient in protein C are at risk for: a) spontaneous hemorrhage b) acute chest syndrome c) vaso-occlusive disease d) thrombosis

d) thrombosis **Protein S and C are naturally occuring anticoagulants.

APEX Q: A patient scheduled for coronary revascularization is diagnosed with type 3 von Willebrand disease. What is the BEST treatment for this patient? a) DDAVP b) plts c) cryo d) vWF/factor 8 concentrate

d) vWF/factor 8 concentrate **Since this patient has type 3 disease, DDAVP will not have an effect. DDAVP would be the answer for a patient with type 1. You could give plts and cryo- but the best answer is vWF/factor 8 concentrate.

Which of the following conditions does NOT precipitate intraoperative coagulopathies? a) massive blood transfusions b) hypothermia c) anemia d) aggressive IVF resuscitation e) goal directed fluid resuscitation

e) goal directed fluid resuscitation ** Aggressive IVF resuscitation leads to dilution of coagulation factors, and is often the most common cause of intraoperative bleeding (versus a lack of functioning platelets). Your most telling factor to identify perioperative bleeding would be a thorough history and physical.

Which factor has the LEAST amount of impact on coagulation? a) garlic b) ginger c) ginko d) fish oil e) magnesium

e) magnesium

Which of the following disorders does NOT cause disseminated intravascular coagulation (DIC)? a) trauma b) burns c) snake bite d) sepsis e) pregnancy f) malignancy g) myocardial infarction

g) myocardial infarction