Blood Transfusion Flashcards
Universal Donor/Recipient
Donor : O-
Plasma Donor: AB+
Recipient: AB+
Plasma Recipient: O-
Rh System
46 rhesus red cell surface antigens with D rhesus antigen = Rh+ will not develop the antibody unless exposed - transfusion of Rh+ to an Rh- -pregnancy with an Rh+ baby to a Rh- mom
Compatibility Testing
ABO-Rh: 5 min, 0.2% risk of reaction after this. ABO incompatibility = most severe transfusion reactions
Antibody screen: to detect non-ABO antigens, 45 min
Crossmatch: mimics transfusion, 45 mins. ensures optimal safety. detects low titer antibodies
Emergency Transfusion without crossmatch
- if known blood type partial 5 min abbreviated crossmatch, confirms ABO
- if unknown O - uncrossmatched (will contain some anti-A anti-B antibodies)
- after 2+ units transfused of O - must continue with it
Massive Transfusion Protocol
1:1:1 RBC: FFP: Platelets
fibrinogen 10 units should increase by 75mg/dL
TXA 1g during infusion, 1 g within 8 hrs after. max
Calcium 1 round (6units RBCs) 1gCaCl or 3g CaGlucaonte
Normals -PT, PTT, Fibrinogen
11-13
25-35
130-330
FFP
All plasma proteins + all coag factors + fibrinogen
FFP Indications
Urgent reversal of warfarin 5-8ml/kg PT > 1.5x normal (>18) PTT > 1.5x normal (>55) Antithrombin III deficiency Massive Blood Transfusion C1 Esterase Deficiency DIC Coag factor assay < 25% (10-20ml/kg coagulopathy)
Platelets
thrombocytopenia < 50,000
eye & neurosurgery < 100,000
known platelet dysfunction
Platelets Considerastions
bacterial infection - sepsis risk stored at room temp (5 days)
1 pack per 10kg of weight
1 unit increase by 10,000
loose ability to aggregate when refrigerated
Cryoprecipitate
fibrinogen, vWB, factor VIII & XIII
VIII - is antihemophillic factor
cryo is slow thawed FFP
Cryo Indications
Hemophilia A
vWB disease
consumption coagulopathy - main use
fibrinogen deficiency (<80-100mg/dL)
Cryo considerations
5 bag pool
admin through filter
complete within 6 hrs of thawing
Whole Blood
RBCs WBCs Plasma Platelet debris Fibrinogen
RBC & blood volume replacement
Fibrinogen
factor I
dose 70 mg/kg
adverse reaction - HA, erythema, N/V, fever, weakness
Prothrombin Complex Concentrates (Kcentra)
factor IX (II, VII, X)
hemophilia B
reversal of anticoagulant agents (warfarin)
DDAVP - desmopressin
Dose and MOA
0.3 mcg/kg stimulates release of vWF releases tPA 2-20 fold increase in VIII - speeds activation of X by IXa releases prostacyclin
DDAVP indications
hemophilia A & vWB disease
ASA induced platelet dysfunction
Recombinant Factor VII
enhances thrombin generation on active platelets
approved for hemophilia A
has thrombotic complications
Aminocaporic Acid (AMICAR) Dose and MOA
synthetic lysine inhibitor of plasminogen.
inhibits fibrinolysis - significant reduction in blood loss & transfusion requirements
dosing: 100mg/kg max 5g over 15 min
OR 10mg/kg/hr throughout surgery
Tranexamic Acid
competitive inhibitor of plasminogen.
rate of DVT unaffected. blood loss in surgery decreased and transfusion requirement decreased.
Hydroxylethyl Starch
Volume expander - polysaccharide
Improve blood rheology - biophysical properties and flow
Acute normovolemic hemodilution
Side Effect: coagulopathy (decreases VIII & vWF)
Dextran
Glucose polymer water soluble
Replace intravascular volume
Stays for 12 hrs
Colloid osmotic pressure 340
Side Effects: allergic reactions, increased bleeding time (decreases platelet adhesion), non cardiogenic pulmonary edema
Acute Normovolemic Hemodilution
Removal of pt whole blood prior to surgery & replacement with non red cell volume.
Improves oxygenation
Prevents hemostasis.
Criteria: high transfusion liklihood, Hgb<12, no infection or significant comorbidities
Transfusion Reaction S/S
Seen under anesthesia: hemoglobinuria, hypotension, fever, flushing, bleeding
Masked by anesthesia: dyspnea, chills, nausea, chest pain
Transfusion Reaction Manifestations
AKI - free hgb in renal tubules = mechanical obstruction. acidic urine increases precipitation
DIC- erythrocin released from RBC activates intrinsic clotting cascade. uncontrolled fibrin formation. consumption of factors I, II, V, VII
Hemodynamic Instability: free hgb activates kalikrinen system = bradykinin. vasodilation
Treating transfusion reaction
stop transfusion alkalize urine - bicarb maintain UOP : IVF, mannitol, lasix sen during & plasma hgb samples to lab check PT, PTT, fibrinogen send unused blood to bank support hemodynamics
Troublesome Events of blood transfusion
alloimmunization HLA antigens allergic and febrile reactions ABT - related mortality (TRALI, TAS, HTI, TTI) intravascular hemolysis
TRALI
indicated with all plasma contains products - primarily PRBCs despite small amount of plasma.
donor anti-HLA antibodies = neutrophil chemotaxis = endothelial damage & capillary leak
- Non-cardiogenic pulmonary edema, dyspnea, cough, fever
-commonly mistaken for TACO
- seen more with blood from multipara women
Hemolytic Transfusion Reactions
ABO antigens or other RBC antigens - donor RBCs ar attack by recipients antibodies
- acute within 24 hrs
- delayed > 24 hrs
TRIM - transfusion related immodulation
occurs against HLA antigens
nonspecific and antigen specific immunosuppression
impaired T cells & decreased macrophages
altered cytokines - IL 1, IL8, TNF
- primary cause is leukocytes within the cells (most PRBCs are leukocyte reduced)
= better outcomes in renal allografts
may increase tumor reoccurrence
Adaptation to Anemia
- oxyhemoglobin shift R - increase 2,3 DPG
- CO increases
- microvasculature alterations - tone
- RAAS - retain Na+ & water
Impact of Pre-op anemia on post-op outcomes
adverse renal and neurological outcomes
o Pre-op anemia and intraoperative blood transfusion are both independent risk factors for adverse outcomes
o Incidence increase with the increase in number of units transfused
Banked Blood
metabolic acidosis - high lactate, low pH low 2,3 DPG low ATP low GSH (antiox) low SNO hb Ical & Mag = 0
Physical Changes Banked Blood
decreased deformability
membrane area decreased
30% dead on arrival
Oxidative Issues banked blood
Hgb oxidation - methgb
Hgb denaturation = free radicals
Bioactive substances in supernatant - cytokines, histamines, lipids, HLA
