Introduction to Transfusion Medicine Yara Park, MD and Araba Afenyi-Annan, MD, MPH Department of...

Introduction to Transfusion Medicine

Yara Park, MD and Araba Afenyi-Annan, MD, MPHDepartment of Pathology and Laboratory Medicine

Scenario 145 year old man with no significant PMH

presents to the ED with 2 day history of coffee ground emesis and dark stools

He also reports dizziness on standing and DOE

Vitals: T 37.1, P 113, BP 102/59, R 24

CBC: WBC 8.4, Hgb 7.3, Hct 22%, plts 243K

Does he need blood?

pRBC TransfusionIndications: PROVIDE O2 carrying capacity

Symptomatic anemiaTachycardia >100 bpmMental status changesECG signs of cardiac ischemiaAnginaShortness of breath, light headedness or

dizziness with mild exertion

AVOID Transfusion based on Lab Values alone

pRBC TransfusionALWAYS exercise sound clinical judgment

Assess tolerance of low HgbAcute anemia: rapid onsetChronic anemia: gradual onset, +/- physiologic

adjustment Increased risk of ischemia - pulmonary disease,

coronary artery disease, cerebral vascular disease, etc.

UNC Indications for pRBC transfusion

Hgb < 8 in asymptomatic patient

Hgb < 11 in symptomatic patient

Acute/anticipated blood loss > 15% TBV

Chronic transfusion regimen

Neonate with blood loss > 10% TBV

Neonate with respiratory distress and Hct < 45%

pRBC TransfusionRBCs suspended in

anticoagulant (citrate based)Additive Solution - AS

Provides nutrients to support RBC metabolism

Volume= 250 to 300 mL 65% RBCs, 35% plasma and AScontains WBC’s and some platelets

Expiration42 days = Shelf life stored at 1-6° C4 hrs of release from Blood Bank, must use within

30 minutes

pRBC TransfusionIndications: PROVIDE O2 carrying capacity

Transfuse slowly within 4 hours release from Blood Bank

1 unit pRBC will increase the average adult recipient’s (70 kg) Hemoglobin by 1 g/dL Hematocrit by 3%

5 ml/kg will increase the pediatric patient’s Hemoglobin by 1 gm/dl, Hematocrit by 3%

pRBC TransfusionRBCs should be infused alone or with

0.9% NaCl through a 170µm clot-screen filter

NEVER mixed with Calcium containing solutions

May cause clumping or clotsDextrose

Hypotonic,may cause hemolysis or clumpingMedicationsHypertonic solutions

AVOID infusing with Lactated Ringers

Next Step – Scenario 1What do we order next?

TypeType and screenType and cross

Blood TypeWHAT IS IT?

Determination of the ABO and Rh (D) types

Performed at room temperature

FRONT TYPE –what’s on the cells? Mix 2 drops of patient cells with 2 drops of reagent

antibodies to A, B and D antigens in different test tubes Agglutination indicates presence of antigen

BACK TYPE – what’s in the serum? Mix 2 drops patient serum with both A and B reagent cells Agglutination indicates presence of antibody

Reciprocal relationship: front and back types must match

Blood TypeFRONT TYPE –what’s on the cells?

Mix 2 drops of patient cells with 2 drops of reagent antibodies to A, B and D antigens in different test tubes, Agglutination indicates presence of antigen

Blood TypeBACK TYPE – what’s in the serum?

Mix 2 drops patient serum with both A and B reagent cells. Agglutination indicates presence of antibody

ABO System

Blood Type

Front TypeAntigen on cells

Back TypeAntibody in serum

A A Anti B

B B Anti A

O -- Anti A, anti BAnti A,B

AB A and B --

Antibody ScreenDetermines if pt has antibodies to other major

blood groups

RequiresCombining pt serum with 3 different RBCs with

known blood group phenotype Incubate at 37 C to detect IgG antibodiesAddition of Coombs serum

Anti-human IgG : enables in vitro agglutination if IgG present

If screen is +, antibody specificity is determined by a more extensive panel of testing RBCs Includes an autocontrolDoes not include a a DAT (Direct Coombs)

ScreenPatient serum + 3 cells of known phenotype

CrossmatchElectronic Crossmatch

For patients without antibodies If patient has an active screen, can get blood w/i

minutes

Immediate Spin Crossmatch Rapid, room temp mixing of patient serum with donor

RBCs to confirm ABO compatibility If patient has an active screen, can get blood w/i

minutes

Full Crossmatch For patients with antibodies Requires incubation and Coombs serum to confirm the

patient’s IgG will not react with donor RBCs Takes ~45 minutes to complete

Sample RequirementsKnow hospital approved policy !

Patient ID Accuracy is Critical #1 cause of fatalities is human error

Primary ID: 2 unique identifiers Full name and MR number Must match exactly with requisition and

Information system Special armband may be required

Secondary Info Date, time of collection, initials of phlebotomist

Unacceptable: unlabeled or hemolyzed

Sample RequirementsSample reflects current immune system

status of patient

> 1 sample per hospitalization may be required

Sample may be used for up to 72 hours

Exception: Pre-care sample which may be used for up to 14 days as long as patient has not been transfused or pregnant in the previous 3 months

P

Scenario 1 (continued)Type: O negative

Screen: Positive

Suddenly, patient has another episode of bloody emesis

Patient is now difficult to arouse, pulse is 140 and he is hypotensive

The blood bank says it will be at least one hour before XM blood available

What are your options?

Emergency Release

Scenario 28 year old girl with Hgb SS disease who presents

to clinic for routine follow-up

Reports no new problems and is doing well in school

Vitals: T 37.1, P 88, BP 110/78, R 18, O2 99%RA

CBC: WBC 8.4, Hgb 7.3, Hct 22%, plts 243K

Does she need blood?

Scenario 2pRBCs are only indicated to provide oxygen

carrying capacity

The patient is stable and doing well

Has high tolerance for anemia

Scenario 2 (continued)Three weeks later, the same patient presents to

the ED with pain in her right leg and back. Is also SOB.

Vitals: T 37.6, P 113, BP 102/59, R 24, O2 92%RA

CBC: WBC 8.4, Hgb 5.3, Hct 16%, plts 443K

Does she need blood?

Scenario 2 – ResultsType: A positive

Screen: Positive and the patient has a history of multiple alloantibodies (anti-C, K, Jka, Fya, s)

With this combination of antibodies, only 0.25% of available units will be compatible

The Blood Bank has 2 units of compatible blood but both are frozen

Frozen UnitspRBCs can be frozen using glycerol and stored

up to 10 years

Often only resource for patients with multiple allo-antibodies

To use, must thaw and wash

WashingTakes ~1.5 hours per unitCan only wash one unit at a timeDecrease recovery of red cells

After thawed and washed, unit expires in 24 hours and cannot be re-frozen

Scenario 365 year old woman with GIB

Transfused during CABG 5 years ago and has 2 children

Warm autoantibodiesIn routine testing, usually all cells react with

patient’s serum

May appear to have specificity but not necessary to determine specificity of the WAA for transfusion purposes

Rule out underlying unexpected alloantibodies

Next StepsDirect Coombs (DAT)

Start with polyspecific If +, then perform the DAT split

Find out transfusion and pregnancy history

Additional testingLow Ionic Strength Solution (LISS)Eluations and AdsorptionsPatient phenotypeSelected cell screens

Conditional Release Card

Transfusing WAA patients-Risks

Difficult to exclude alloantibodies

Transfusion may stimulate alloantibody production

Transfusion may intensify the autoantibody

Transfusion may suppress erythropoiesis

Destruction of transfused cells may increase hemoglobinuria and hemoglobinemia

Transfusing WAA patientsFor patients who are rapidly hemolyzing,

transfusion is often required as a life-saving measure

Can be challenging due to the complex laboratory work-up and the acute clinical needs

Transfusion should not be held solely because of serologic incompatibility

Transfuse the smallest amount possible to maintain an adequate oxygen level, not to reach an arbitrary number

Transfusing WAA patientsUsually well tolerated

Transfused cells may not survive any longer than the patient’s own cells

Scenario 417 year old male with AML, s/p 2 rounds of

chemotherapy presents for next treatment

During therapy, platelet count falls to 18,000 and patient experiences hematuria

What are the transfusion options?

PlateletsPooled platelet concentrates (PC’s) from several

whole blood donations6 pack, 4 pack, 10 packMultiple donors = One therapeutic dose

Platelets, apheresis one donor, one donation, one or more therapeutic

doses

Suspended in citrated plasma

Stored at 20-24º C up to 5 days only

Very susceptible to shortages!!!

Blood Collection/ Manufacturing

Whole Blood DonationDonor whole blood centrifugedSeparated in after collection by centrifugation

into pRBCPlatelet rich plasma (platelet concentrate)Plasma (FFP)

Blood Collection/ Manufacturing

Blood Collection/ Manufacturing

ApheresisAutomated centrifugal blood separatorDonor whole blood separated on line to

collect one or more componentspRBCPlatelet, apheresis = 6 platelet concentratesPlasma (FFP)

Apheresis Separators

Automated apheresis blood separators may be used for donation or therapeutic applications

PlateletsPLT surface

ABO antigens but not RhPlatelet specific AgsHLA- A and HLA-B

Contain trace amounts RBC’s making Rh type importantRh- female gets Rh- PLT

Indications for PLT Transfusion

Thrombocytopenia: quantitative defectsProphylactic transfusion for PLT <10kFor invasive procedure, trauma , bleeding with PLT

count <50kRapidly falling PLT count with bleeding

Platelet dysfunction: qualitative defectsUremiaAspirin ingestionPost- Cardiopulmonary Bypass

PlateletsOne therapeutic dose of PLTs

Apheresis or 6 pooled platelet concentrates

platelet count 30-50k

Scenario 4 (continued)The patient undergoes his third round of chemo

and requires multiple pRBC and platelet transfusions

He now is in his fourth round of chemo and is again thrombocytopenicMonday 4 AM plts 9 K Transfused

1 apheresis pltTuesday 3 AM plts 11K Transfused 1

apheresis pltWeds. 4 AM plts 10K Transfused 1

apheresis plt

Is he responding to plts?ANSWER: Need to check 1 hour post counts

Differentiate increased consumption from refractoriness

Wednesday 4AM plts 10KTransfused 1 apheresis platelet at 6AMPost-count Wednesday 7:30AM plts 11K

Appears to not be responding appropriately= Refractory

Platelet RefractorinessMonitor efficacy of transfusion by measuring PLT

count within 1 hour of transfusionConserve precious resourcesMinimize transfusions and risksAssist in recognizing platelet alloimmunization vs.

consumption

Common causes of “refractoriness” BleedingFeversHepatosplenomegalyAlloimmunization

Platelet AlloimmunizationSeen in patients who receive many transfusions

Usually caused by HLA Class 1 antibodies

Order HLA antibody screen (PRA) to test for antibodies and also order HLA type

If PRA is positive, blood bank will order HLA-matched platelets

Other option, platelet drip (also used for ITP patients with life/organ threatening bleeds)

Scenario 563 year old man presents to the ED with fevers

and AMS

Wife reports flu-like symptoms for previous 48 hours, now confused and difficult to arouse

PMH: Prostate CA, HTN

Vitals: T 39.2, P 108, BP 76/45, R 22

PE: Altered man in moderate distress

Scenario 5 (continued)Labs:

WBC 23K, Hct 42%, plts 107KPTT 37.7s, INR 1.3, fibrinogen 68D-Dimer 13,000Blood cultures: gram negative rods

What is the best product for him?

Fresh Frozen PlasmaFFP

200-300 mL +Frozen within 8 hrs of collectionStored -18º C for up to 1 yearOnce thawed, can be kept at 1-6º C for 24 hrs

Contents:1 unit/mL of all clotting factors including labile

Factors V and VIII~400 mg fibrinogenCitrate as anticoagulant

FFP IndicationsTreatment of multiple coagulation factor

deficienciesMassive transfusionTraumaLiver diseaseDICUnidentified deficiency

Warfarin reversal prior to emergent invasive procedures (5-8 ml/kg)

PT/PTT > 1.5x normal

DOSE: 10-15 ml/kg to attain 30% Factor level

CryoprecipitateCold insoluble white precipitate that forms when

FFP is thawed at 1-6º C

Removed from FFP by centrifugation and refrozen at –20º C

Once thawed, kept at room temperature

CONTAINS:80 to 150 IU Factor VIII:C (antihemophilic factor)150 mg fibrinogenVon Willebrand FactorFibronectinFactor XIII

CryoprecipitateEach unit =10-15 mL

Pool 10 units = typical adult dose

Indications:Deficiency of fibrinogen, Factor VIII or XIII Improve platelet function in uremia

Dose calculation based on Patient’s weight and hematocrit : plasma volume Desired increase in Factor level

Scenario 5 (continued)For this patient, cryoprecipitate is the

appropriate product

Can provide large doses of fibrinogen in a small volume

Component ModificationsPooling

Split

Cryopreservation (freezing)

Leukocyte Reduction

Washing

Irradiation

Leukocyte reductionFiltration with specialized leukocyte removing

filtersPre-storage vs. Post-storage

Indications:Prevent CMV transmissionPrevent alloimmunization to leukocyte antigens

in patients who will require chronic transfusionPrevent recurrent febrile non-hemolytic

transfusion reactions

May require special request depending on hospital policyAt UNCH, all pre-storage leukocyte reduced

RBCs/PLTs

WashingRemoval of plasma by washing RBC or platelets

with saline

Indicated :For prevention of severe allergic reactionsAnaphylaxis IgA deficiency

Time consuming, labor intensive, delays transfusion, decreases transfusion increment slightly, changes expiration date (24 hours)

Does not substitute for leukocyte reduction

IrradiationPrevent graft versus host disease (GVHD)

Blood products from blood relatives and HLA matched products must be irradiated due to similar HLA antigens

Indicated in severe immunodeficiency settings (lymphopenia)BMTHematopoietic malignancies undergoing

chemotherapyPremature infants and IUTSevere combined immunodeficiency

DisadvantagesChanges product expiration date (28 days from

irradiation) Increased potassium

Scenario 66 year old boy with AML and neutropenic fevers

is given a unit of pRBCs for Hgb of 7.6 g/dL and SOB

30 minutes into the transfusion, the patient complains of chills and back pain

What is the next step?

STOP THE TRANSFUIONDo Not Restart the Unit

Scenario 6 (continued)The differential includes:

Hemolytic transfusion reactionFebrile non-hemolytic transfusion reactionBacterial contamination/sepsisUnderlying disease

Suspected ReactionHemolytic reaction symptoms are not specific

and include:FeverChillsHypotensionOozing from IV siteBack painHemoglobinuia

If any of these occur STOP transfusion, provide appropriate supportive care, notify blood bank

Send repeat samples for blood bank evaluation

DO NOT restart the unit

Blood Bank Work-UpSerum color check

DAT (Direct Coombs)Determines if antibody is coating red cells

Culture

Retype patient

Adverse Effects of Transfusion

Acute Transfusion Reactions < 24 hours

Immune AllergicHemolyticFebrile, non-hemolyticAnaphylacticTransfusion related acute lung injury (TRALI)

Adverse Effects of Transfusion

Delayed Transfusion Reactions > 24 hours

Immune HemolyticGVHDPlatelet refractorinessPost transfusion Purpura

Development of anti-platelet antibodies

Adverse Effects of Transfusion

Transfusion Reactions Non-Immune

AcuteCirculatory Overload (Volume excess)Septic shock from bacterial contamination of blood

product

Delayed Iron Overload Infectious Disease transmission

Transfusion Transmitted Disease Risks

Infectious Agent or Outcome Estimated Risk per Unit Transfused

Estimated % of Infected Units that transmit or cause clinical sequelae

Virus

HIV-1 and -2 1:1,400,000-1:2,400,000 90

HTLV-1 and –II 1:256,000-1:2,000,000 30

HAV 1:1,000,000 90

HBV 1:58,000-1:147,000 70

HCV 1:872,000-1:1,700,000 90

WNV ? ?

B19 parvovirus 1:3,300-1:40,000 Low

Scenario 745 year old man with colon cancer, currently

undergoing chemotherapy

Presents to clinic with epistaxis and platelet count of 15,000

Given one unit of platelets

Scenario 7 (continued)Five minutes into the transfusion, the patient

develops SOB

O2 saturation drops from 99% to 82% on room air

What is in the differential

Differential DiagnosesTransfusion Related Acute Lung Injury (TRALI)

Allergic/anaphylaxis

Transfusion Associated Circulatory Overload (TACO)

Scenario 822 year old woman with menorrhagia who

presents to clinic with SOB and dizziness

Reports prolonged heavy bleeding

Vitals: T 37.1, P 115, BP 85/60, R 20

PE: Pale, fatigued appearing woman; flow murmur

Scenario 8You decide she needs pRBCs

How do you consent her for blood/blood products?

Basic Principles of Informed Consent

1. Consent is a process

2. Requires comprehension by patient

3. Voluntary & free from coercion

4. Not legally binding

5. May be revoked at any time

6. Prospective

Elements of Informed Consent

Information to the patientExplanation of interventionBenefits RisksAlternativesOpportunity for questions/clarification

Availability of choices (including refusal)

Autonomous patient decision

Documentation of process

Products Requiring Informed Consent

Consent Required Consent Variable

Blood Components-whole blood or apheresis derived

Plasma derived proteins

HPCs- any source Recombinant Proteins

Minimally processed tissues; femoral heads, corneas, heart valves, reproductive tissues

Highly Processed Tissue: Bone plugs

Procedures Requiring Informed Consent

Consent Required Consent Variable

Donor-Patient HPC collection, Preoperative

Autologous donation

Acute normovolemic hemodilution

Therapeutic Phlebotomy Intraoperative blood recovery & reinfusion

Therapeutic apheresis Postoperative blood recovery & reinfusion

Physician Responsibility

Formulate a course of action based on clinical expertise, judgment, and best available information

Give the patient enough information about the plan to make an independent decision about whether or not to accept recommendation.

Information to Patient

Statement of patient’s medical condition

Explanation of interventionBenefits

Relief of symptoms, prevention of complicationsLikelihood of achieving goal

RisksAlternativesPrognosis with or without intervention

Patient Discussion PointsNeed for transfusion

BenefitsTreatment such as increase O2 carrying capacityPrevention such as preoperatively for potential

coagulation factor or platelet lossStatement of the likelihood of success

RisksClinician to determine

Standards for Risk Disclosure No national standard

Professional organizations State laws

Case Law Reasonable Patient Standard Simple Subjective Standard Reasonable Physician

Risks of Transfusion: What to disclose?

Infectious disease risks-see table

Noninfectious disease risksMost common include allergic, FNHTR

Rare but potentially fatalAcute HTR, Bacterial contamination, TRALI

Patient specificCoexisting morbidities, previous reactions How problems would be handled, potential long

term impacts

Alternatives to TransfusionPreoperative autologous donation

Erythropoietin

Intraoperative conservation techniquesAcute normovolemic hemodilutionBlood salvage and reinfusion

Blood substitutes are not an option!

Right of RefusalConsequences of refusal

Must complete separate formRefusal to the Use of Blood or Blood Products

Scenario 935 year old woman with no PMH presents to the

ED with fatigue, fever and petechiae

Lab work reveals Hct 22%, platelet count 8K, LD 3100

On peripheral smear, many schistocytes

Of note: BP normal, HIV negative, pregnancy test negative

Thrombotic Thrombocytopeni

c Purpura

Definition of TTPFirst described in 1924 by Moschowitz in a 16

year old female

Classic pentad of symptomsHemolytic anemiaThrombocytopeniaFeverRenal failureAltered mental status

Diagnostic CriteriaMany causes of microangiopathic hemolytic

anemia (MAHA)

For diagnosis of TTPMinimum criteria

MAHAThrombocytopenia

Other causes excludedOnly 34% of patients present with all features of

pentad

Peripheral Smear

Autopsy Findings

Picture courtesy of Dr. Mark Brecher

Classification of TTPPrimary or idiopathic TTP

Secondary TTPTransplantChemotherapyHIVDrugsConnective tissue disordersHormonal (pregnancy)

Normal Processing Activity

P-selectin

ULvWF

Weibel-Palade Body

HospitalsUNC

Normal Processing Activity

HospitalsUNC

TTP Pathophysiology

HospitalsUNC

TTP Pathophysiology

HospitalsUNC

TTPEmergent plasma exchange (TPE)

1 PV daily1.3 to 1.5 PV may be used in refractory

patients or those severely affected

Plasma is replacement of choice

Platelet count >150 K (x 2-3 days)

LDH “normal”

Watch out for anemia (may need RBCs)

FFP infusions if TPE delayed

Apheresis

A Greek word that means to separate or remove

Apheresis Terms Therapeutic Procedures

Cytoreductive ApheresisPlasma Exchange, TPE, or Therapeutic

PlasmapheresisRed Cell Exchange or ErythrocytapheresisPhotopheresisImmunoadsorption

Methods of Separation Filtration

Plasma removal only

CentrifugationWBC removalPlatelet removalRed cell removalPlasma removal

Centrifugation Methods

Continous FlowTwo access linesFasterSmaller extracorporeal volume

Centrifugation MethodsDiscontinous Flow

Single need accesVolume fluctuations

ASFA Treatment Categories

Category ITherapeutic hemapheresis is standard and

acceptable therapy

Category IIGenerally acceptable, considered to be more

supportive to other treatment

Treatment Categories Category III

Evidence is insufficient to establish the efficacy

Category IVControlled trials have shown lack of efficacy

Emergent Indications

TTP

Hyperviscosity syndrome

Pulmonary Renal SyndromeGoodpasture’s, ANCA with DAH

Sickle Cell Crises (Hgb SS, SC, S-Thal)ACS, Stroke/TIA, hepatic sequestration

Cytoreduction for leukemia, essential thrombocytosis

Hypervisocity Syndrome

Hyperviscosity SyndromeWhole blood viscosity related to Hct, RBC

aggregation, plasma proteins, and interactions with the vasculature

When viscosity increases, fragile endothelium can be damaged

Hypervisocity SyndromeWaldenstroms Macroglobulinemia, IgM

Myeloma

Viscosity poor correlation with clinical symptoms

Concurrent anemia may confound diagnosis

Elevated total protein, total Ig, UPEP, SPEP

Hydration trail, chemotherapy

Certainty of diagnosis : risk vs benefit

IgG

300 KDa

IgM

900KDa

Torlonib 2000

colloid-osmotic pressure

IgMInwards Forces

outward forces

Extravascular Space

Intravascular

Space

Torloni MD 2000

13

Role of TPECategory I

Remove excess Ig to rapidly normalize viscosity Percent

intravascularConcentrationg/L or mg/mL

T1/2 days

IgM 76 1.2-4.0 5-6IgG 45 8.0-16.0 18-23

IgA 42 0.4-2.2 5-6.5Albumin 40 3.2-5.6 17

Fibrinogen 80 1-4 3-5

Practical ConsiderationsOne plasma volume exchange

Calculated PV will not equal actual PV

Usually 1-2 TPEs will relieve symptoms

Replacement fluid 5% albumin (with addition of crystalloid)

Inwards Forces

Outwards Forces Outwards

Forces

Inwards Forces

Free water pulled into vessel Free water pulled out of vessel

Be aware of BP fluctations!

Pulmonary-Renal Syndromes

Pulmonary renal syndrome

Goodpasture’s Syndrome (Category I)

Wegener’s/ANCA (Category II)

Daily with plasma (1 PV) until pulmonary hemorrhage subsides then every other day for a total of 6 – 9 procedures)

5% albumin once risk of bleeding subsides

Anemia may require RBC transfusion

Goodpasture’s SyndromeResults from the presence of an IgG anti-

glomerular/ alveolar basement membrane antibodies (detected by radioimmunoassay in over 90% of cases).

It represents a Type II immune reaction (cytotoxic antibody mediated).

Males are affected more than females (9:1)

Goodpasture’s SyndromeThe majority of patients present in their mid-

twenties with hemoptysis (75%- due to diffuse pulmonary

hemorrhage), hematuria (due to glomerulonephritis), anemia, hepatosplenomegaly, and hypertension.

Pulmonary symptoms will generally proceed the renal disease by weeks to months, many patients also have laboratory evidence of renal

disease at the time of presentation (microscopic hematuria).

Anti–GBM/ Goodpasture’s Syndrome

Lung/kidney damage mediated by anti-GBM

Two Goals: Two concurrent strategies

Removal of anti-GBMTPE

Suppress its synthesisSelf-limited: 6-12 monthsCyclophosphamide + steroids (pulse)Azathioprine

Anti–GBM/ Goodpasture’s Syndrome

PLAN for TPE: Recommendations vary4 TPE exchanges (of at least 1 plasma volume)

1st weekThen alternate days (qoD)Total of 6 –9 treatments over 2- 3 weeksFollowing titer pre and post exchange Immunosuppresive drugs should be continued longerFollow serum IgG as a surrogate: <200 mg/dL

Consider risk of Ig removal and increased risk of infection

Wegener’s Granulomatosis, ANCA, etc.

Necrotizing granulomatous vasculitis, C-ANCA positive

ANCA, Wegener’s, other RPGN

Patients presenting with RPGN

Anti-neutrophil cytoplasmic autoantibodiesMPO or PR3 specificity

+/-pulmonary hemorrhageDiffuse Alveolar Hemorrhage =DAH

ANCA/Wegener’s/RPGNWith DAH

Emergent TPE usefulDAH can be fatalDaily TPE with FFP replacement to prevent

dilutional coagulopathyOnce DAH subsides, complete TPE series qoDGenerally 7 TPE procedures over 2 weeks

Sickle Cell Disease

Sickle Cell DiseaseMost commonly Hb SS

Sickled RBC have shortened life-spans, leading to hemolytic anemia and microvascular occlusions

Patients can have vaso-occlusive eventsPain crisesAcute chest syndrome (ACS)StrokePriapismSplenic, hepatic, and renal dysfunction

Indications for Erythrocytapheresis

Category I for life and organ threatening complications

EMERGENTStroke: CVA or prophylactic chronic RBC exAcute Chest Syndrome with progressive

respiratory insufficiency

URGENTPriapism : as adjunct when primary therapy

failsPre-operative to minimize risk of SSD

complications during anesthesia

Cerebrovascular DiseaseIncidence of Stroke: 6-10%

11% of patients will have a CVA by age 2050% will have a second stroke within 3 years

without intervention

75% due to vascular occlusion

25% from hemorrhage

Stroke Risk FactorsTranscranial Doppler

Measurement of Average Velocity Normal 130cm/sec Increase risk of Stroke

> 200cm/sec

High velocity may cause narrow vessel to collapse or clot to form.

Benefits of Exchange

Rapid increase in Hemoglobin A

Euvolemia

Simple Transfusion = Hyperviscosity

Reduction in Fe Load

Drop in platelet count

Suppression of hematopoeisis

Practical ConsiderationsDetermine goal :

70% Hgb A, Acute chest70-90% Hgb A, strokeFinal Hct

Blood Units set up time consumingC, E, K negative, sickle trait negative

Get type & screen and Hb/Thal panel sent stat

Check on patient RBC phenotype/prior blood bank records here and afar

Therapeutic Apheresis in Leukemia/

Thrombocytosis

CytoreductionAcute leukemias: leukostasis

Usually high blast %

WBC when symptoms generally beginMyeloid >100,000Lymphoid >400,000Monocytoid > 50,000

Sxs: pulmonary and CNS

Category I

CytoreductionMay be profoundly anemia due to marrow

inflitration

RBC transfusion may be required

Anemia can lead to similar CNS sxs as hyperleukocytosis

May need to decrease WBC to safely transfuse

CytoreductionGenerally one time procedure

May need to repeat if patient becomes symptomatic again or chemotx delayed

Central line usually required

Hetastarch used to increase WBC removal efficiency

ThrombocytosisSeen with essential thrombocythemia and

polycythemia vera

At risk for thromboembolic events (plt count >^600K)

Can have bleeding (plt count >1.5 million)

Plateletpheresis is rarely used; must be used in conjunction with plt-lowering agents

Category II

ResourcesBlood Bank Staff: 966-4011

TMS Attending/Fellow/Resident on call 24/7

McLendon Lab Websitehttp://labs.unchealthcare.org/

Always welcome to do a rotation on TMS!