Blood Transfusions

Question 1

Indications for RBCs transfusion

Answer 1

• Symptomatic in a normovolemic patient regardless of H/H
• Acute blood loss w/ evidence of inadequate O2 delivery
• Hemoglobin <7 in a hemodynamically stable hospitalized patient

Question 2

How much volume in a Unit of RBCs

Answer 2

~300ml (200ml of red cells)

Question 3

1 Unit of RBCs raises H/H by how much?

Answer 3

1g/dL and 3% unless active bleeding

Question 4

What can happen to K, after transfusion of 1 unit

Answer 4

causes +10 mEq since K leaks out of red cells in stored blood; monitor in CKD

Question 5

Citrate

Answer 5

• present in stored blood
• can result in metabolic alkalosis (citrate~bicarb).
• Ionized calcium may be decreased from calcium+citrate complexing

Question 6

Indications for Platelets

Answer 6

• Platelet count of <10 in non-bleeding patient w/ marrow suppression
• <20,000 for most bedside procedures
• consider higher threshold (<30,000) for patients who are febrile/septic
• <50,000 if actively bleeding ; and before surgery
• <100,000 if CNS bleed, or before ocular or CNS procedure

Question 7

One apheresis unit should raise platelet count by ______?

Answer 7

30K within 1 hour

Question 8

Platelet refractoriness = ?

Answer 8

defined as increment of <10K on two or more occasions

Question 9

FFP contains ….?

Answer 9

all coagulation factors

Question 10

FFP indications : ???

Answer 10

• Active bleeding in the setting of an INR >1.5 (includes in the setting of liver disease, DIC, warfarin overdose, vitamin K deficiency)
• INR>2 in non-bleeding patient scheduled for surgery or invasive procedure
• Maybe TTP (plasma exchange is preferred)

Question 11

INR of FFP…?

Answer 11

as high as 1.5, and generally doesn’t correct the INR to below 1.6

Question 12

Cryoprecipitate contains : _________?

Answer 12

VIII, XIII, vW F, fibrinogen and fibronectin

FFP that is thawed at 4 degrees C

Question 13

Indications for transfusion of cryoprecipitate: ???

Answer 13

Fibrinogen < 100 mg/dl in the setting of consumptive coagulopathy (DIC) or severe bleed

Other Uses:

• Treat von Willebrand’s disease when DDAVP unsuitable.
• Alternative to factor concentrate in Hemophilia A

Question 14

Leukoreduced blood components :_________?

Answer 14

– Removal of leukocytes through filtration to <106. Done to prevent complications of PRBC transfusion related to WBCs (transfusion reaction, CMV infection). Most hospitals automatically do this for PRBCs now.

Question 15

Indications for leukoreduced product:????

Answer 15

• Chronically transfused patients (HLA sensitization)
• Potential or previous transplant recipients
• Patients w/ previous febrile non-hemolytic transfusion rxn
• CMV seronegative at-risk patients (b/c CMV lives in white cells)

Question 16

DIFFERENT PREPARATIONS: …..?????

Answer 16

• Leukoreduced
• Irradiated
• Washed
• CMV neg

Question 17

Irradiated blood components : ????

Answer 17

Red cells that are exposed to at least 2500cGy of Gamma radiation to destroy the ability of T lymphocytes to divide. Done to avoid transfusion-associated GVHD.

Question 18

Indications for irradiated product:????

Answer 18

• Severe congenital immune deficiency
• Immunocompromised transplant recipients (especially BMT)
• Transfusions from family members
• CLL or other patients being treated with fludarabine chemotherapy
• Hodgkin lymphoma
• Consider in patients with solid tumors being treated with aggressive chemo

Question 19

Washed blood components : ????

Answer 19

Blood is washed to prevent infusion of proteins present in residual plasma in red cell concentrates that may cause allergic reaction.

Question 20

Indications for washed product:?????

Answer 20

• Patients with severe or recurrent allergic reactions
• Documented IgA deficiency (pt’s can have anti IgA antibodies)
• Reduce plasma K levels in acute renal failure

Question 21

CMV negative components - ?????

Answer 21

Includes leukoreduced and seronegative CMV products.

Question 22

Indications for CMV negative components:????

Answer 22

• CMV negative allogeneic BMT

- Immunosuppressed CMV negative patients, potential transplant candidates

Question 23

Transfusion Reactions, some general stats about prevelance…?

Answer 23

Overall, 1-6% of all patients, and up to 10% of heme/onc patients who receive blood transfusions experience an adverse reaction.

Question 24

PREMEDICATIONS FOR TRANSFUSION to prevent transfusion reactions

Answer 24

Generally recommend APAP 650mg PO and benadryl 50mg PO, maybe dex

Question 25

Name the types of transfusion reactions: ????

Answer 25

▪ Febrile non-hemolytic transfusion reactions
▪ Acute hemolytic transfusion reactions
▪ Delayed hemolytic transfusion reactions
▪ Anaphylactic transfusion reactions
▪ Urticarial transfusion reactions
▪ TRALI
▪ Post transfusion purpura
▪ Graft-versus-host disease (GVHD)

Question 26

Chemical/Physical Reactions from transfusion : ????

Answer 26

▪ Volume overload (TACO)
▪ Citrate toxicity
▪ Hyperkalemia, Hypokalemia/metabolic alkalosis

Question 27

Febrile Non-hemolytic Reactions:

Answer 27

▪ Most common reaction (0.5-1% of pRBC transfusions)
▪ fever, chills, dyspnea, and malaise 1-6 hours after transfusion
▪ From cytokines that generated/ accumulate during the storage of blood
▪ Benign and without any lasting sequelae, BUT cannot distinguish initially from acute hemolytic reactions SO the initial treatment for both the same
▪ Treat by STOPPING the transfusion, IVFs, draw appropriate labs, and ANTIPYRETICS
▪ Prevented by using leukoreduced or washed products

Question 28

Acute Hemolytic Reactions: ???

Answer 28

• 1 per 40,000 transfused units
• Medical emergency from rapid destruction of donor RBC’s by preformed recipient antibodies
• Most commonly due to ABO incompatibility from clerical error
• classic triad of fever, flank pain, and red/brown urine (hemoglobinuria) is actually RARELY seen. Other symptoms include chills, flushing, nausea, chest tightness, malaise
• STOP the transfusion, notify blood bank to checks for clerical errors, Maintain ABC’s, start IVF’s (Normal Saline),
• Maintain UOP of 100-200 ml/hr with IVF’s to avoid renal failure
• Labs: direct antiglobulin (Coombs) test, Hemoglobin, and repeat Type&Cross from the other arm.
• DO NOT USE Lactated ringers (calcium in this may initiate clotting of any remaining blood in the line) or dextrose containing IVF’s (dextrose may hemolyze any remaining RBC’s in the line)

Question 29

Delayed Hemolytic Reactions:

Answer 29

• 1 per 7000 pRBC transfusions
• Time course is within 2 to 10 days after transfusion.
• Signs/Symptoms are falling hematocrit, slight fever, mild increase in indirect bilirubin, spherocytosis on smear
• No treatment is required unless brisk hemolysis is present.

Question 30

Anaphylactic Reactions:

Answer 30

• 1 per 20,000 to 50,000 transfused units
• Occurs within few seconds to minutes following initiation
• due to the presence of class-specific IgG, anti-IgA antibodies in patients who are IgA deficient
• Selective IgA deficiency occurs in 1 in 300-500 people
• Anaphylaxis (tachycardia, urticaria, flushing, laryngeal edema, hypotension, respiratory distress)
• Stop transfusion, Epinephrine (0.3 ml of 1:1000 solution IM), possible IV epinephrine gtt, Airway, IVF’s, occasionally pressors
• Prevented by using washed blood products

Question 31

Transfusion-Related Acute Lung Injury (TRALI):

Answer 31

• Actually under reported…one series found 1 in 2000 transfusions at a university hospital
• ARDS type of picture 30 minutes to 6 hours post transfusion…not related to volume overload
• Treatment is supportive