Transfusion Medicine Resident Rounds November 1, 2001 Adam Oster.

Transfusion Medicine

Resident Rounds

November 1, 2001

Adam Oster

Case 1

• 45 male with known esophageal varicies

• presents with 2 hours of hematemesis.

• O/E– 120, 100/60, 20, 96%

– normal LOC

– no hematemesis presently

• Principles of management;– NG and consider

airway control.

– volume• NS

• ?blood

– octreotide• 50 bolus and 50 iv

infusion

Case 1

Type and Screen• ABO grouping

• Rh typing

• antibody screening of patients serum

• Usually takes 45 minutes

• more time is required for specific antibody identification if the screen is positive.

Type and Screen:Blood Grouping

• requires patient RBCs, serum or plasma

• presence of AB antigens are determined by testing with anti-A and anti-B

• Cells that agglutinate only with anti-A– type A

• Cells that agglutinate with both– type AB

• Cells that don’t agglutinate with either– type O

Type and Screen: Blood Grouping

• Rh status determined by examining the reaction with anti-D

• Anti-B and anti-D– type B +

• anti-A and anti-B, none with anti-D– AB -

• only anti-D– O +

Type and Screen:Blood Grouping

• Other blood group systems– Kell, Kidd, Duffy,

MN, SsU, Lewis, P, Ii• uncommonly may be

the cause of intravascular hemolytic reactions. Usually not reactive at 37C.

• Usually only exhibit decreased survival

Type and Screen:Antibody Screening

• For irregular alloantibodies

• Screen cells are group O with known anitgenic content

• 2 major classes of antibodies– Complete and

Incomplete antibodies

– Complete Antibodies• aggulinate RBCs in

saline . Usually IgM. Responsible for HTR.

– Incomplete Antibodies

• require special techiques to make their agglutination visible. Usually IgG. Not responsible for HTR

Type and Screen:Antibody Screening

• Possible screening results;– all antibody screens

are negative• recipient has no

(detectable) unexpected antibodies.

• Donor blood can be released following an abbreviated or electronic cross-match.

– one or more screen cells are positive

• patient has one or more unexpected antibodies

• antibody needs identification

• donors must be shown to be antigen-negative.

• full cross-match required.

Type and Screen:Antibody Screening

• Coombs Test– direct and indirect

– direct: • antihuman globulin (anti-

IgG and anti-complement) added to test cells. Observe for agglutination.

– Agglutination suggests that IgG antibodies in the test (patients) serum have bound to recipient RBCs

– Indirect Coombs• patients serum and

reagant RBCs (with known antigens) are mixed. Antihuman globulin added.

– Agglutination suggests presence of antibodies in test serumcapable of hemolyzing RBCs.

Selection of RBCs for Transfusion

• Specimen from recipient must be obtained within previous 3 days if they have been pregnant or transfused within the previous 3 months.

• Donor:– ABO and Rh confirmed. If

Rh -, Rh typing must be repeated.

• Recipient– ABO and Rh typing

determined– serum screened;

• Set of reagent type O which express 18 clinically relevant antigens.

• Cells incubated with recipient serum and then indirect Coombs carried out.

Selection of RBCs for Transfusion

• If screening is positive then spcific identification is required and transfusion is ideally witheld.– Atypical antibodies in

patients requiring transfusion is 1-2%

Limitations of Pre-Transfusion Testing

• A HTR if the patients antibody if too weak to be detected

• a non-hemolytic reaction

• hemolytic reaction due to patient misidentification.

• Adverse reactions; hyperkalemia, citrate toxicity, volume overlaod.

• Prevention of transmittable diseases.

Selection of RBCs for Transfusion

• Cross-Match– demonstrates

compatibility of test RBCs with recipient.

• Immediate spin cross match -- mixes patient serum with donor RBCs, spinning the tube and reading the results immediately.

– Only detects ABO incompatibility.

– Complete cross-match

• if antibodies are detected in the antibody screening.

• Donor units lacking the specific antigen should be selected and an indirect anitglobulin test performed on each unit.

The Electronic Cross-Match

• Computer-assisted crossmatch in which donor blood is issued based on the blood bank information system (computer) ensuring that the patient and donor are ABO-compatible.

• No clinically significant antibodies are detected in the current blood sample and there is no record of clinically significant antibodies in the past.

• The patients’ ABO group and Rh type has been done twice

and entered in the computer

The Electronic Cross-Match

Contraindications• a record of clinically

significant antibodies (even if they are now undetectable)

• currently detectable clinically significant antibodies

• unresolved ABO discrepancies

Advantages of the Type and Screen

• Better use of donor blood, as it is not tied up by being crossmatched and held for patients who probably will not need it.

• Potential for a more economic transfusion service due to decreased blood inventory requirements, decreased reagents, and more efficient use of technologist time

Case 2

• A 72 year-old woman with a history of gastrointestinal bleeding is brought to the emergency room after being found slightly confused at home by one of her neighbors. Her blood pressure on arrival is 110/60 mmHg, and her pulse is 110 beats/minute. She is OB positive.

• CBC; 70, 140, 8.2• lytes;

– Na 160; K 5.0– Cr 150 – INR norm; PTT

elevated.– Management of

hemorhhage• volume, protamine sulfate

and pRBCs– immediate blood?

Case 3

• Unrestrained river in a high speed MVC

• Prolonged extrication time

• EMS;– intubated and began iv

volume resuscitation.

• On arrival in the ED;– intubated and

paralyzed.

– 140, 80/40, 36.5

Case 3

• Resuscitation– volume

– blood• type and screen with

cross match (approx 1 hour)

• other options?

• Selection of Blood for Emergency Transfusion– Group O should be used– if unmatched blood is

required take a sample from donor bag and recipient for antibody screen and cross-match.

– If group is known, may give un-crossmatched blood of same group.

Emergency Blood Transfusions

• 70 woman with a bleeding ulcer. – Presented; 80/50, 120,

20 and with decreased LOC. She is known type A.

• in addition to volume resuscitation, blood type...

– A+ or A-

• 23 woman with LLQ pain and blood PV for 6 hours.– Presents 180, 90/60, 20

and with decreased LOC.

• Blood type– O -

– if she were known type AB

» AB -

Emergency Blood Transfusions

• 45 male GSW to left buttocks.– Presented 70/30, 150,

20, decreased LOC.• Blood type

– O

• Group O blood– transfusion under

emergency circumstances is usually safe

• some group O blood will cause hemolytic reactions if antibody titre is >1:250.

• Removal of antibody-containing serum has reduced the incidence.

Case 4

• 47 woman receiving 1st unit of pRBCs post-elective TAH and BSO.– Acute onset chest pain,

diaphoresis and temperature.

– VS: 120, 100/70, 24, 96% on RA, 39.5C

• Immediate Reactions– Hemolytic Reactions

• an antigen-antibody reaction resulting in immediate intravascular hemolysis

– produces hemoglubinemia and hemoglobinuria.

– Hypotension, renal failure and DIC may develop.

Immediate Transfusion-Related Reactions: HTR

• Management;– stop transfusion

– prevent shock and renal hypoperfusion.

• Aggressive fluid therapy

• pressors and lasix

• ensure adequate ventilation.

• Transfusion reaction w/u

– If hemodynamically unstable, to ICU for invasive monitoring.

– Even without evidence of hypotension dopamine (1 to 5 mcg/kg/hr) may be beneficial for its protective renal effects.

– Lasix will help to maintain adequate urine output.

Transfusion Reactions

Immediate Delayed

Hemolytic Non-hemolytic

HemolyticTransfusion

ReactionFebrile Allergic

Hypo-calcemia

Hyper-Kalemia and

Acidosis

AcuteLungInjury

Infections Allergic

Transfusion Reactions

• 72 male receiving blood post lower GI bleed.– Complains of malaise

and chills.

– VS: 120/70, 70, 39.0C

– Reaction type?• Febrile non-hemolytic

• 23 woman receiving 1st unit post ectopic vaginal bleed.– Complains of skin

flushing and throat tightness.

– O/E resp distress.

– VS: 120, 100/70. 38.0, 26, 87% on 5L

• Reaction?– anaphylactic

Transfusion Reactions

Immediate Delayed

Hemolytic Non-hemolytic

HemolyticTransfusion

ReactionFebrile Allergic

Hypo-calcemia

Hyper-Kalemia and

Acidosis

AcuteLungInjury

Infections Allergic

Transfusion Reactions

• Anaphylactic Reaction– Management;

• 10ml of 1:10 000 iv epi

• iv antihistamine

• iv steroids (solu-medrol)

– note; anaphylactic reactions usually occur only the IgA-deficient.

Transfusion Reactions

• 50 male 4 days post 2 unit transfusion after anterior resection of gastric ca.– Complains of jaundice.

– O/E jandiced. VSS, afebrile.

• Reaction – delayed hemolytic.

• Delayed Hemolytic Reaction– extravascular

hemolysis usually due to antibodies against non-ABO systems.

– Hemolysis, hypotension and ARF.

– Lab work?

– Management?

Delayed Transfusion Reactions

• Infections– HBV 1:2 000 000 units– HCV 1:3 300-6 600 units– HIV 1:225 000 units– all blood is tested for; HbsAg, anti HTLV-I/II,

anti HIV 1 and 2, anti-HCV and syphilis.

Transfusion-Associated Coagulopathies

• Dilutional– thought to occur when

large volume replacement therapy consists of only pRBCs and non-blood volume

– e.g. 1.5x patient blood volume

– follow with PTT, INR

• DIC– 30% of transfusion-

related coagulation abnormalities.

– If DIC panel suggestive then 4U FFP if no signs of bleeding, 6U if bleeding

Case 5

• 17 male unrestrained on passenger side. Ejected from vehicle. Known to be on chemo for NHL. – Found to have a large

hemothorax pushing on the mediastinum.

• Initial resuscitation is complete.

• CBC comes back;– 80, 2.5, 10.0x109/L

platlets.

– ?thrombocytopenic

– further blood product therapy.

• Platlet transfusion

Platelet Transfusion

• Should be ABO-specific. Not routinely x-matched.

• do not carry Rh antigens.• Amount to transfuse

– 1U theoretically increases platlets approx 5-8 x 109/L

– usually 1U/10kg or 6U/transfusion episode

• Considering a platelet transfusion?– Cause of thrombocytopenia

– competence of the remaining hemostatic system

– platelet function and number

– presence and likelihood of bleeding

– hazards of transfusion.

Platelet Transfusion

• High risk of spontaneous bleeding– plts <20– minimal risk at >50

• Decision to transfuse depends on present clinical urgency and the likelihood that a tranfusion will be beneficial.

• 45 male with thrombocytopenia secondary to marrow failure and a brisk lower GIB.

• Hemodynamically stable.

• Transfuse?

Platelet Transfusion

• 17 with splenomegaly (?secondary to lymphoma). Platelets 20. Presents with altered LOC, meningismus and fever.

• ?LP• Transfuse then LP?

• 2 yo girl with plt 1. Dependent petichiae. No apparent active bleeding.

– Where should you look?

• Transfuse?• If bleeding from gums?

– IV IgG and ?tranfuse for transient benefit.

Platelet Transfusion

• 32 with aplastic anemia. Splenic laceration after falling while skiing.

• Transfuse?

• 50 male. Thrombocytopenic and septic. Acute pulmonary hemorrhage.

• Transfuse?

Platelet Transfusion

• 18 male with ALL. Recent chemotherapy has made him pancytopenic. Multiple platelet transfusions in the past.

• Bleeding from gums and anus.

• Transfuse?• 6U platelets matched

for type increase his count by 3.

• Refractory to transfusion. Why?– Pre-existing

alloantibodies.

Case 6

• 65 woman with a history of IHD and chronic atrial fibrillation presents with 6 hours of epistaxis.Conservative management has failed to stop the bleeding.

• O/E pale and uncomfortable.– 96, 110/70, 18.

• CBC – 80, 400, 8.2

• INR 3.3; PTT normal.• Management?

– FFP and pRBCs

Case 6b

• 43 known alcoholic. • Presents with a

witnessed seizure. Intubated by EMS. CT head showed a large epidural bleed with shift.

• INR 2.1

• Management?

Fresh Frozen Plasma

• FFP contains all factors of the soluble coagulation system, including the labile factors V and VIII.

• FFP is indicated when a patient has multiple factor deficiencies and is bleeding.

Case 7

• 30 year-old pregnant woman presents to the emergency room with third trimester vaginal bleeding and the sudden onset of pelvic pain. Fetal monitoring shows severe fetal distress and ultrasound reveals placental abruption.

• An emergent cesarean section is performed. A few minutes after the infant is delivered, the vaginal bleeding increases notably.

INR = 1.50

PTT = 150 seconds

Platelet count = 15 X 109/L

Hematocrit = 25%

Fibrinogen = 30 mg/dL

FDP = high

DIC

• A consumptive coagulopathy. Circulating thrombin results in the widespread generation and deposition of fibrin in small blood vessels.

• platelets, fibrinogen, and coagulation factors, especially Factor V and Factor VIII are consumed.

• Fibrinogen is disproportionately affected, compared to other clotting factors.

• Management– platelets

– cryoprecipitate• contains fibrinogen,

factor VIII coagulant, vonWillebrand's factor, and factor XIII.

– Dose?

Case 8

• 35 woman with classic Hemophilia. Presents with hematemesis. She has known esophageal varicies secondary to a congenital hepatic malformation.

• Management– determine %activity

FVIII

– give FVIII

– 250-300U/10ml

Case 9

• 40 homeless woman with a 24 hr history of a dirty, infected looking lesion on the bottom of her foot.

• She has no recollection of ever getting any vaccines.

• Management?– Tetanus toxoid and tetanus

IVIG

• 32 G1P0, 9/40• RLQ pain and small

amounts of blood PV.• Vag. U/S shows the

uterus to be empty and fluid in the pelvis. She is AB-

• Management.– 50mug Rhogam