Hematology (Acquired Bleeding Disorders)

Front 1

name 3 most common causes of acquired bleeding disorders

Back 1

DIC
liver failure/dz
Vit K deficiency

Front 2

petechiae is characteristic in: platelet defect or coagulopathy?
-what about hemarthroses (joint bleeding)?
-what about deep hematomas?
- what about family hx?
- what about superficial bruising?

Back 2

-platelet defect
-coagulopathy
-coagulopathy
- sometimes in platelet defects, but common in coagulopathy
- characteristic in platelt defect (small, multiple large, solitary), common in coagulopathy

Front 3

in taking history, what is the diff b/w local vs. systemic bleeding?

Back 3

-Single area suggests a structural defect

- Multiple sites suggests a systemic defect

Front 4

which physical findings support platelet versus a coagulation factor etiology for bleeding.

Back 4

platelet defects = mucocutaneous bleeding (nose bleed, menorrhagia), petechiae

coagulation factor defects = intramuscular or intra-articular bleeding, mucocutaneous bleeding (epistaxis, menorrhagia), NO PETECHIAE

Front 5

liver disease causes of acquired coagulation disorder that decreases synthesis of all clotting factors, except factor ___ and ___.

what else does it cause clinically?

Back 5

VIII; XIII

also causes:
- dec clearance of fibrin degradation products (=FSP)
- thrombocytopenia (due to congestive splenomegaly or decreases in TPO production, since it happens in the liver)

Front 6

why do pts with hemophilia have thrombocytopenia?

Back 6

2 reasons: low TPO or hepatosplenomegaly (since spleen is storage site for platelets)

Front 7

what lab results would you expect in liver dz?

Back 7

prolonged PT and PTT

Front 8

therapy of liver dz

Back 8

mainly transfusion with fresh frozen plasma (FFP) = which contains all coagulation factors

can give cryoprecipitate, if pt has extremely low fibrinogen

- give platelets for thrombocytopenia

Front 9

A 46 year old man with severe liver failure awaiting liver transplant.

PT 36.3 sec, PTT 48.5 sec, fibrinogen 98 mg/dL
D-dimer 2.8 mg/mL (moderate positive)
Factor V 4%, factor VII 2%, factor VIII 169%

Dx?

Back 9

liver dz leading to prolonged PT and PTT, also decreased coagulation factors, except for factor 8

Front 10

is there ever primary DIC?

Back 10

no, it is always secondary to clinical conditions.

Front 11

what is DIC?

Back 11

pathological activation of coagulation (blood clotting) mechanisms that happens IN RESPONSE TO VARIETY OF DZ. Leads to formation of small blood clots inside blood vessels throughout body. As small clots consume all the available coagulation proteins/platelets, normal coagulation is disrupted and abnormal bleeding occurs from skin, the GI tract, the resp tract and surgical wounds. Small clots also disrupt nl blood flow to organs (such as kidneys), which may malfxn as a result.

Front 12

T or F. in DIC, clotting and bleeding may happen at the same time.

Back 12

T.

Front 13

name the 3 most common causes of DIC

Back 13

Pregnancy (obstetric complication)
Infection
Malignancy
Promyelocytic leukemia (M3)

"PIMP"

Front 14

is FDP or FSP elevated or depressed in DIC? what does this do?

Back 14

elevates; this FSP will inhibit stable clot formation and platelet function--> this is why pts bleed

Front 15

how do you make dx of DIC?

Back 15

-based on clinical/lab findings
-pts must have predisposing conditions
- typically, pt is bleeding DIFFUSELY

Front 16

what would you expect on the lab tests result of DIC?

Back 16

-PT prolonged and D-dimer should be positive
- PTT may be prolonged or normal or even shortened
- platelet/fibrinogen may be decreased or normal
- schistocytes may appear on PBS

Front 17

what does D-dimer positive mean?

Back 17

indicates BOTH ongoing coagulation and fibrinolysis

If the D-dimer reads high, then further testing (ultrasound of the leg veins or lung scintigraphy or CT scanning) is required to confirm the presence of thrombus.

Front 18

what do you base your dx of DIC on?

Back 18

Make dx based on: inc PT (increased coagulopathy) and D-dimer positive (hypercoagulable state - means thrombin formation)

Front 19

tx of DIC

Back 19

-treat underlying cause
-supportive care (maintain BP)
-replacement therapy for bleeding (ie. platelets)

Front 20

which factors are affected by vitamin K deficiency? what actually happens?

Back 20

factors, 2,7,9,10 and protein C and S (these are all made in the liver and require K gamma-carboxylation)

so vit k deficiency is assoc with decreased activity of these factors adn a hemorrhagic tendency (you can't clot!!)

Front 21

vit k is necessary for __- _________ of glutamic acid in the liver in these factors

Back 21

gamma - carboxylation

Front 22

what are 2 risk factors for vit K deficiency?

Back 22

prolonged antibiotic therapy AND/OR malnutrition (like in osteomyelitis where pt is receiving antibiotics but also can't eat for a while)

Front 23

lab findings of vit k deficiency

Back 23

-prolonged PT and PTT times
- low factors 2, 7,9, and 10
- low protein C and S

Front 24

tell me about PT and PTT

Back 24

prothrombin time = monitors the extrinsic pathway and the time it takes for a sample of a pt's blood to clot after adding tissue factor. if vit K, for example, is deficient, then time to clot will be prolonged due to lower amounts of factor 7 (which is crucial to this pathway). PT time can be useful in making sure warfarin therapy (which is a Vit K antagonist) does not go too far and cause dangerous levels of bleeding

PTT = can be useful to monitor coagulation factors and clotting time involved in the intrinsic pathway. also can be used to monitor heparin therapy (which acts on factor 9-antithrombin) and make sure that pt's anti-coagulation therapy does not go to dangerous levels

Front 25

Dx of vit k deficiency

Back 25

there are 2 ways:
1) confirmed by correction of the PT time upon administering vit K
2) measurement of factor 2, 5, and 7 will yield normal factor 5 (bc it's not vit K dependent) and decreased factors 2 and 7 (bc they are!)

Front 26

what is the extrinsic pathway?
what about the intrinsic pathway?
what is the common pathway?

Back 26

7,10,5,2,1
12,11,9,8,10,5,2,1
10,5,2,1

Front 27

tx of vit k deficiency?

what is effective for urgent reversal?

Back 27

oral/parenteral vit k

FFP (fresh frozen plasma)

Front 28

name the cause of acquired coagulopathy that is characterized by massive transfusions of rbc's so that there's not enough coagulation factors or platelets to coagulate

Back 28

dilutional coagulopathy (therefore, to prevent this, always give FFP along with red cell transfusions)

Front 29

name the condition that causes acquired coagulopathy, frequently occuring in pts with hemophilia A or B, that is characterized by autoimmune disorder that causes IgG's to self coagulation factors.

name the most common factor target.

Back 29

spontaneous factor specific inhibitor

factor VIII