Hemostasis, bleeding, and blood transfusions Flashcards

1
Q

Review Clotting Cascade.

Bleeding may occur with a deficiency of any factors except for which factor?

A

.

Factor XII.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Hemostasis:

  • lab tests
  • -what is each one
  • -which factors are being assessed
A

Platelet count (150K-400K)

PT: measures ability of blood to form stable clot. Factors VII, X, V, prothrombin, and finbrinogen (Extrinsic Pathway)

PTT: evaluates adequacy of fibrinogen(I), prothrombin(II), factors V, VIII, IX, X, XI, XII (intrinsic/common pathways)

Bleeding time: time from injury to cessation of bleeding from both wounds is measured.

Thrombin Time: evaluates fibrinogen to fibrin conversion with an external source of thrombin (time to clot formation)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

PTT is used to assess UFH or Warfarin?

PT/INR is used to assess UFH or warfarin?

What is the PTT in patients with VII deficiency?

What is the normal range of Bleeding Time?

What would cause a prolonged Thrombin time?

A

UFH.

Warfarin

Normal, b/c PTT measures the intrinsic pathway.

Bleeding Time: normal is 5-10minutes

Prolonged fibrin time:

  • low fibrinogen levels
  • abnormal fibrinogen
  • fibrin and fibrinogen split products
  • heparin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Von Willebrand Dz:

  • pathophysiology
  • site of bleeding
  • inheritance
  • MC in which gender?
  • Lab study results
  • tx
A

Patho: reduced factor VIII activity and von willebrand activity

Site Bleed: mucocutaneous

Inheritance: autosomal dominant

MC in women and men

Labs:

  • prolonged PTT
  • normal PT
  • abnormal platelet function

Tx:

  • cryoprecipiatate infusions
  • DDAVP (releases VW from endothelial cells)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Hemophilia A

  • pathophys
  • site of bleeding
  • MC in which gender
  • lab study results
  • tx
A

Patho: reduced or absent factor VIII activity

Site bleed: joints and intramuscular

MC in men

Lab results:

  • prolonged PTT
  • normal PT
  • normal platelet function

Tx:
-purified factor VIII products

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are some acquired bleeding disorders?

A

advanced liver dz

anticoagulation therapy

acquired thrombocytopenia

platelet inhibiting drugs

uremia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Liver Dz:

-how does this cause bleeding disorder?

A

Inability to synthesize proteins leads to decreased levels of prothrombin(II) and factors V, VII, and X.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Anticoagulation therapy:

  • what is warfarins effects on the clotting cascade?
  • what agent reverses warfarin?
  • what is heparin effects on the clotting cascade?
  • what agent reverses heparin?
A

Warfarin:

  • depression of clotting factors II, VII, IX, X
  • reversed with FFP or vit K in an emergency

Heparin:

  • increased speed of antithrombin III (inhibiting the clot), binds to and neutralizes IX, X, XII
  • reversal with protamine sulfate
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the 3 mechanisms of acquired thrombocytopenia?

What are some platelet inhibiting drugs?

Drugs associated with bleeding?

A

3 mech:

  • decreased platelet production in bone marrow
  • increased destruction of platelets in peripheral blood (heart valves)
  • splenic pooling in enlarged spleen

Platelet inhibitors:

  • ASA
  • NSAID
  • Plavix

Drugs:

  • warfarin
  • heparin
  • plavix
  • ASA
  • Herbal:
  • garlic, ginger, ginko, ginseng, st johns wort
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Intraoperative Bleeding: SHOCK:

-tx

A

Tx:

  • massive transfusion of PRBC
  • controlled with gelfoam, surgicel, floseal, tisseel
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Post op bleeding:

  • MC cause
  • other causes
  • what are the three main categories of post op bleeding?
A

MC cause: poor hemostasis during surgery

Other:

  • residual heparin
  • shock
  • altered liver function

3 main categories:
-primary bleeding: occurs during operation.

  • reactive bleeding: happens within 24hrs of operation, hemorrhage rxn from ligature coming loose from vessel.
  • secondary bleeding: 7-10d post op, erosion of vessels, usually seen with bad infection.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

DIC:

  • characterized by what?
  • results
  • cause
A

Characterized by intravascular coagulation and thrombosis that is diffuse instead of localized at site of injury.

Results in systemic deposition of platelet fibrin microthrombi that causes diffuse tissue injury…..death.

Cause:

  • release of tissue debris into bloodstream after trauma or obstetric catastrophe
  • extensive endothelial damage to vascular wall
  • hypotension
  • operations with large blood loss (prostate, lung, malignant tumors,)
  • burns, sepsis, snake venom
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

DIC

  • dx
  • lab results
  • tx
A

Dx:
-diminished levels of coagulation factors and platelets

Labs:

  • prolonged PT and PTT
  • hypofibrinogenemia
  • thrombocytopenia
  • presence of fibrin and fibrinogen products (d-dimer)

Tx:

  • remove precipitating factors
  • severe DIC:
  • -cryoprecipitate best method to replace fibrinogen loss
  • platelet transfusion
  • FFP
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are the 5 types of transfusable RBC

A

Whole blood

Packed red blood cells

Washed red blood cells (gets rid of plasma)

Leukoreduced (irradiated) red blood cells

Divided or pediatric unit

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

One unit of packed red cells into an average 70kg person raises the HCT ___% and hgb by ___g/dL

Describe the difference between type/screen and type/cross?

A

one unit of packed red cell into a 70kg person raises the hct by 3% and hgb 1g/dL

Type/Screen: dont have bleed ready to go, they just know which type of blood to get if they need it.

Type/Cross: type your blood and get the transfusable ready to go.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is FFP?
Indications for use of FFP?

Does FFP contain albumin?

A

platelet poor plasma removed from whole blood.

Indications:

  • lab evidence of coagulation factor deficiency with clinical bleeding
  • need for invasive procedure

maybe?

17
Q

Platelet Transfusion:

Indications for Platelet transfusion?

Labs?

Transfusion of 6 platelets raise count by how much?

A

thrombocytopenia d/t platelet dysfunction.

Labs:

  • bleeding time (increased)
  • whole blood platelet function testing

Transfusion of 6 platelets raise count by 50K - 100K

18
Q

Complications of Blood transfusions?

A

Metabolic derangements

immunologic rxns

infection complications

volume overload

pulmonary complications

19
Q

Complications of blood transfusions:

-what are the MC metabolic derangements?

A

Metabolic derangements:

  • hypocalcemia
  • hyper/hypokalemia
  • hypothermia
20
Q

Complications of blood transfusions: HYPOCALCEMIA:

  • clinical presentation
  • cause
A

clinical presentation:

  • muscle tremors
  • ST segment prolongation
  • Delayed T waves

Cause: rapid transfusion

21
Q

Complications of blood transfusions: HYPER/HYPOKALEMIA:

-cause

A

Cause: high levels of K+ are found in unites of blood frozen longer than 35days
-after transfusion K is taken up by the red cell causing hypokalemia

22
Q

Complications of blood transfusions: HYPOTHERMIA

-cause

A

Cause: you really should put blood through a warmer to prevent this.
Complications of blood transfusions

23
Q

Complications of blood transfusions: IMMUNOLOGICAL RXNS

-what are these?

A

Febrile rxn

acute and delayed hemolytic rxns

thrombocytopenia

anaphylactic shock

urticaria

graft vs host dz

immune suppression

24
Q

Complications of blood transfusions: Febrile rx:

  • mc cause
  • presentation
  • tx
A

MC cause: as a result of antileukocyte abys

Present with:

  • fever/chills
  • tachycardia

Tx:
-pretreat with ASA, antipyretics, and antihistamines

25
Q

Complications of blood transfusions: HEMOLYTIC RXN:

  • mc caus e
  • presentation
  • tx
A

MC cause: ABO-mismatched blood

Presentation:

  • hot or cold flushing
  • chest pain
  • low back pain
  • fever
  • hypotension

Tx: stop transfusion and recheck blood

26
Q

Complications of blood transfusions: GRAFT VS HOST DZ:

  • MC cause
  • presentation
  • prevention
A

MC cause: happens when immunosuppressed pts recieve donor leukocytes

Presentation: fever, rash, liver dysfunction, diarrhea

Tx: prevent with leukocyte-reduced red cells or irradiated red cells

27
Q

Complications of blood transfusions: INFECTIOUS AGENTS:

  • Cause
  • sx
A

Cause: bacteria(from platelets), viruses (hep B, C, HIV), parasites

Sx: fever, chills, tachycardia, hypotension

28
Q

Complications of blood transfusions: TRANSFUSION RELATED LUNG INJURY:

  • MC in what type of blood product?
  • sx
  • tx
A

MC with units that contain plasma (FFP or platelets)

Sx: pulmonary edema after transfusion

Tx: supportive may require intubation*

29
Q

Complications of blood transfusions: MASSIVE TRANSFUSION:

  • occurs when?
  • complications
A

occurs when transfusing more than 10 packed red cells in 24hrs or pts total volume in 24 hrs or half of pts blood volume in 1 hr.

Complications:

  • dilutional coagulopathy
  • oxygen transport abnormalities
  • electrolyte/acid-base derangements
  • hypothermia
  • dz transmission
  • ARDS
30
Q

Autologous blood transfusion:

  • what is this?
  • when is this done?
  • why might you do this?
A

WHat; collection and re-infusion of pts own blood

Done:

  • pre-surgical donation
  • intraoperative cell saver

Reasons

  • fully compatible
  • no risk of transmission
  • less dependent on blood bank
  • pt with rare blood types