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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!