2 BENEFITS Enhanced oxygen carrying capacity Improved homeostasis with blood component therapyVolume support of Cardiac output
3 BLOOD COMPONENT THERAPY Whole bloodPacked Red Blood CellLeukoreduced Red Blood CellFresh Frozen PlasmaCryoprecipitatePlatelet concentrateProthrombin ComplexSingle Donor Plasma
4 PACKED RED BLOOD CELLContain same amount of Haemoglobin as whole blood, but much of plasma has been removed.Haematocrit 70%,whereas whole blood 40%Reconstituted with 5% Dextrose,0.4% saline,5% Dextrose in 0.9% saline,0.9% saline and Normosol-R with a ph of 7.4.
5 STORAGE OF BLOODCitrate phosphate Dextrose Adenine (CPDA-1) anticoagulant preservative in which Blood stored at 1 degree celsius-6 degree celsiusAddition of Adenine to CPD solution allows RBC to synthesize ATP and extend storage time from 21 days to 45 days.Shelf life can be further extended to 42 days AS-1(Adsol),AS-3(Nutricel) or AS-5(Optisol)Citrate-anticoagulant,phosphate-buffer,dextrose-red cell energy sourceAdsol-Adenine,Glucose,mannitol and sodium chloride,citrate hct-70%Nutricel-Glucose,Adeninine,Citrate,Phosphate,Sodium chloride and mannitolOptisol-Dextrose,Adenine,sodium chloride and mannitol
6 INDICATION FOR TRANSFUSION The Practice Guidelines for Blood Component Therapy developed by the American society of Anaesthesiologists (ASA) state that “red blood cell transfusion is rarely indicated when the hemoglobin concentration is greater than 10 g/dl and is almost always indicated when it is less than 6 g/dl”
7 COMPENSATORY MECHANISMS DURING ANEMIA Increased Cardiac outputRedistribution of Cardiac outputIncreased Oxygen extractionChanges in Oxygen-Hemoglobin affinity
8 COMPARISON OF WHOLE BLOOD AND PACKED RED BLOOD CELL VALUEWHOLE BLOODPACKED REDBLOOD CELLVolume(ml)517300Erythrocyte mass (ml)200Hematocrit(%)4070Albumin(g)12.54Globulin(g)6.252Total Protein(g)48.836Plasma sodium(meq)4515Plasma Potassium (meq)Plasma Acid (meq)8025Donor-to-recepient ratio1 unit per patient1 unit per 4-6 patients
9 CONDITIONS THAT MAY DECREASE RBC TRANSFUSION THRESHOLD Impaired oxygenationPulmonary diseaseHigh altitudeIncreased oxygen demandHyperthermiaHyperthyroidismSepsisPregnancy
10 Contd….. Limited ability to increase Cardiac Output Coronary artery diseaseMyocardial dysfunctionβ-Adenergic BloackadeInability to redistribute cardiac outputLow SVR statesOcclusive vascular diseaseLeft shift of Oxygen-Haemoglobin curve
11 Contd…. Abnormal Haemoglobins Presence of recently transfused Hb (decreased 2,3-DPG)Hb S (sickle cell disease)Acute Anemia (limited 2,3-DPG compensation)Ongoing or imminent blood lossTraumatic/surgical bleedingPlacenta previa or accreta,abruption,uterine atonyClinical coagulopathy
12 PLATELET CONCENTRATES Prepared by differential centrifugation of whole blood or by plateletpheresis techniques.Stored at room temperature;satisfactorily kept for 7 days.Platelet concentrate transfusion,third leading cause of transfusion-related deaths (following sepsis).One unit of platelet concentrate will increase platelet count of a 70-kg recepient by ,000/µL;One apheresis unit →30,000-60,000/µL
13 INDICATIONS FOR TRANSFUSION American Society of Anesthesiologists (ASA) Task force recommendations:Prophylatic platelet transfusion is ineffective and rarely indicated when thrombocytopenia is due to increased platelet destruction (eg.idiopathic thrombocytic purpura)Prophylatic platelet transfusion rarely indicated in surgical patients with thrombocytopenia due to decreased platelet production when platelet count >1,00,000 and usually indicated when platelet count > 50,000
14 INDICATIONS FOR TRANSFUSION contd…. Surgical and obstretic patients with microvascular bleeding usually require platelet transfusion if platelet count >1,00,000 and usually indicated platelet count <50,000;Therapy to be based upon patients bleeding risk.Vaginal deliveries or operative procedures ordinarily associated with insignifcant blood loss maybe undertaken in patients with platelet count <50,000.Platelet transfusion maybe indicated despite an apparently adequate platelet count if there is known platelet dysfunction and microvascular bleeding.
15 FRESH FROZEN PLASMAContains all plasma proteins particularly factors ν and νιιιASA task force recommended the administration of FFP with the following guidelines:For urgent reversal of Warfarin therapy;dosage 5-8ml/kgFor correction of known coagualation factor deficiencies for which specific correlates are unavailaible
16 FRESH FROZEN PLASMA contd.. For correction of microvascular bleeding secondary to coagulation factor deficiency in patients transfused with more than 1 blood volume and when prothrombin and partial thromboplastin time cannot be obtained in a timely fashion.Calculated to achieve a minimum of 30% plasma factor;dosage ml/kg.Contraindicated for augmentation of plasma volume or albumin concentration.
17 INDICATIONS FOR FFP ADMINISTRATION Replacement of isolated factor deficienciesReversal of Warfarin effectAntithrombin ιιι deficiencyTreatment of immunodeficienciesTreatment of thrombotic thrombocytopenic purpuraMassive blood transfusion(when factors ν and νιιι < 25% normal)Requirements of above points if PT atleast 1.5 times longer than normal
18 CRYOPRECIPITATEPrecipitate that remains when FFP thawed slowly at 4 degree celsiusPrimarily contains factor νιιι and fibrinogen;also has Von Willebrand factor and fibronectinAll other plasma proteins in traceUsed in Haemophillia A and fibrinogen deficiency treatment.
19 CRYOPRECIPITATE contd…. ABO compatibility not must.Administered within 6 hours after thawing.One unit increases fibrinogen levels by 5-7 mg/dL
20 COMPLICTIONS OF BLOOD TRANSFUSION Development of various infectionsTransfusion associated reactions(Hemolytic transfusion reaction)Transfusion related lung injuryLeft shift of oxygen dissociation curveCoagulopathy noticed with massive transfusionsK meq in stored blood on day
21 COMPLICATIONS OF BLOOD TRANSFUSION contd…. Dilutional ThrombocytopeniaLow levels of factor ν and νιιιDisseminated Intravascular Coagulation like syndromeCitrate Intoxication and HyperkalemiaHypothermiaAcidosisTransfusion associated Graft versus Host DiseaseAdverse ocular reactionTransfusion related immunomodulation
22 RISKS OF BLOOD TRANSFUSION Type Occurrence in Red Blood Cell Units TransfusedInfectiousHuman immunodeficiency virus in 1.4–2.4×106Hepatitis B in 58,000–149,000Hepatitis C in 872,000–1.7× 106Bacterial infection in 2,000Immunologic reactionsFebrile nonhemolytic transfusion reactions in 100Anaphylactic transfusion reactions in 20,000–50,000ABO mismatchHemolysis in 60,000Death in 600,000Leukocyte-related target organ injury in 20 to 1 in 50Transfusion-related acute lung injury in 2000Post-transfusion purpura RareTransfusion services error in 14,000
23 HEMOLYTIC TRANSFUSION REACTIONS Signs and symptoms:ChillsFeverChest and flank painNauseaHemoglobinuriaBleeding diasthesis(noticed during surgery)Hypotension
24 STEPS IN TREATMENT OF A HEMOLYTIC TRANSFUSION REACTION STOP THE TRANSFUSIONMaintain urine output at a minimum of ml/hr(generous fluid administration,mannitol,furosemide)Alkalinize the urineAssay urine and plasma hemoglobin concentrationsDetermine platelet count,partial thromboplastin time and serum fibrinogen levelsReturn unused blood to blood bank for repeat cross matchSend patients blood and urine sample to blood bank for examinationPrevent hypotension to ensure adequate renal blood flow
27 BLOOD CONSERVATIONSIncreasing interest in in Blood conservation since last 15 yearsSignificant risks of allogenic blood transfusion.Shortage of allogenic bloodPatient choiceImprovement in availaibilty of transfusion alternatives.
28 HIGH RISK PREDICTORS Advanced age Low preoperative red blood cell volume(preoperative anemia or small body size)Preoperative antiplatelet or antithrombotic drugReoperative or complex proceduresEmergency operationsNoncardiac patient comorbidities
29 INTERVENTIONS TO LIMIT BLOOD TRANSFUSION Pharmacologic agents:Hemostatic Drugs with Antifibrinolytic PropertiesErythropoetinDDAVPRecombinant factor 7 ADevices to Aid Blood conservation:Cell SaverVentilator-assisted Blood Conservation PEEPOxygenator typesPerfusion Blood PumpsHeparin Bonded CircuitsLeukocyte Filtration
30 INTERVENTIONS TO LIMIT BLOOD TRANSFUSION contd…. Perfusion techniques and OPCABHeparin ManagementProtamine dosingAcute Normovolemic HemodilutionPreoperative autologous Blood transfusionMinimized extracoporeal bypass circuitsRetrograde autologous primingHemofiltrationOff-pump procedures for Blood conservationTopical agents/Tissue Glues
33 Aprotonin: Pharmocokinetics: Inactive via oral route Rapid distribution into extravascular spaceFollowing redistribution plasma half life aprox.150 minsLess than 10% excreted as unchanged drugSlowly degraded as lysosomal enzymesTerminal elimination phase half life-10 hr
34 Aprotonin: Mechanism of action: Inhibhits serine proteases that attenuates:Inflammatory responsesFibrinolysisThrombin generationInhibhits pro-inflammatory cytokine release and maintains glycoprotein homeostasis
35 Aprotinin- Mechanism of Action Blood/Surface activationIntrinsic PathwayPlasminKallikreinHeparinNon Specific Serine Antiprotease:AprotininComplement activationClottingFibrinolysisKininsCytokines/ Adhesion MoleculesSystemic Inflammatory response
36 Aprotonin-dosage:1-2 million KIU followed by a continous infusion of 100, ,000 KIU/hr
38 Lysine Analogues: Epsilon Amino Caproic Acid Tranexemic acid MOA: They inhibit plasminogen by binding to the lysine binding sites on the plasminogen molecule.Spare platelet function by inhibiting the deleterious effects of plasmin.Tranexamic acid is similar in action to Epsilon-aminocaproic acid but it is approximately 10 times more potent.
39 Lysine Analogues: Dose: Intravenous loading dose of 10 mg/kg for tranexamic acid followed by 1 mg/kg/hrmg/kg of ε-aminocaproic acid followed by infusions of 25 mg/kg/hr
40 Erythropoeitin:Endogenous glycoprotein-stimulates red cell production in response to hypoxia and anemia.Recombinant EPO: Reduce preoperative anaemia in patients undergoing autologous blood donationSafe and effectiveDrawbacksExpensiveHypertensionLag period: 4-6 days-less effective post operativelyBeta blockers and cardiopulmonary bypass inhibit effectDoseU/kg s/c or I/v 3 times a week
41 Desmopressin (DDAVP): ReleasesEndogenous factor VIII precursorsVon Willebrand factorTissue type plasminogen activator.Not helpful prophylactically to reduce bleeding after cardiac procedures.Helpful in patients with demonstrable and specific platelet dysfunction known to respond to this agent (eg, uremic or CPB-induced platelet dysfunction, type I von Willebrand’s disease).Dose0.3 μg/kg iv, sc or intranasal
42 Recombinant Factor VIIa: Vitamin K-dependent glycoproteinCurrently FDA approved only for the treatment of severe bleeding episodes in hemophiliacs with factor inhibitors or patients with FVII deficiencyBinds to tissue factor→ Activation of factor X (FXa) on the platelet surface (a phospholipid surface);FXa + Activated factor V→ prothrombinase complex → Thrombin formation.
43 Recombinant Factor VII a: Plasma concentrations ~50 nM→ partial Thrombin GenerationPlasma concentrations ~ 100 to 150 nM → Full activation of Thrombin (Thrombin burst)Recommended dose for bleeding in hemophiliac patients is 90 µg/kg i.v.Doses for the treatment of uncontrolled hemorrhage varied from 15 to 180 µg/kg i.vRecommended as rescue therapy for severe intractable bleeding without an identifiable surgical source that is unresponsive to routine approaches after cardiac procedures using CPB.
45 Cell Salvage Techniques: AdvantagesDisadvantages↓ risk of infection↓ risk of transfusion reactionSafer in patients with rare blood groups & multiple antibodiesNo immunosuppression? Acceptable to Jehovah’s Witnesses↓ demand for allogenic blood products↑ cost- setup cost inc. staff trainingUnused blood wasted↑ risk of bacterial contamination
46 Ventilator-assisted Blood Conservation: Positive End Expiratory PressureIncreased end-expiratory airway pressure (PEEP) exerts mechanical pressure on the myocardium and may limit microvascular bleeding after heart surgery.Use of prophylactic PEEP postoperatively is not effective.
47 Oxygenator Type:Membrane oxygenator systems during cardiopulmonary bypass are preferred for reduction in blood utilization and improved safety.AdvantagesFewer cerebral emboliBetter biocompatibilityReduced blood utilization
48 HEPARIN-BONDED CIRCUITS: Heparin coating of the oxygenator or of the entire bypass circuitLimits platelet activationReduces complement activationAlters cellular adhesion to the bypass tubingDiminishes the inflammatory pulmonary injury seen after CPBNeed of Low dose Heparin & consequently reduced protamine dose
50 ACUTE NORMOVOLEMIC HEMODILUTION (INTRAOPERATIVE AUTOLOGOUS DONATION): Removal of one to two units of blood immediately before surgeryTo maintain circulating blood volume, the volume is replaced with crystalloid / colloid.Contraindications:Evolving acute myocardial infarctionUnstable anginaCardiogenic shockPreoperative anemiaSepsisknown bacteremia.Relative contraindicationsLow EF (< 30%)
51 ACUTE NORMOVOLEMIC HEMODILUTION: PrincipleLowering the red blood cell concentration (hematocrit) during surgery decreases the reduction in red cell mass lost for any given volume of blood lost.In cardiac surgeryThe blood removed before the institution of CPB is “protected” from the potential deleterious effects of platelet activation and consumption, hemolysis, complement activation, and the production of a variety of inflammatory cytokines associated with extracorporeal circulation
52 PREOPERATIVE AUTOLOGOUS BLOOD DONATION: Autologous blood donation of as much as 2 units a few days to a few weeks preoperatively.Not routinely employed in cardiac surgery, because of possible increase in the incidence of myocardial infarction or hemodynamic instability.Useful in carefully selected (mostly elective) patients particularly when coupled with appropriately dosed erythropoietin therapy and/or iron therapy.
53 Contraindications to participation in autologous Blood Donation programmes: Evidence of infection and risk of bacteremiaScheduled surgery to correct Aortic StenosisUnstable anginaActive Seizure disorderMyocardial Infarction or CVA within 6 months of donationPatients with significant Cardiac or Pulmonary diseaseHigh grade left main coronary artery diseaseCyanotic heart diseaseUncontrolled hypertension
54 Advantages/Disadvantages Prevents transfusion transmitted diseasePrevents red cell alloimmunizationSupplements the blood supplyProvides compatible-blood for patientsPrevents some adverse transfusion reactionsProvides reassurance to patients concerned about blood risksDoes not effect risk of bacterial contaminationDoes not effect risk of ABO incompatibility errorIs more costly than allogenic bloodResults in wastage of blood not transfusedIncreased incdence of adverse reactionsSubjects patients to perioperative anemia and increased likelihood of transfusion
55 Postoperative Blood Collection: Recovery of blood from surgical drains followed by reinfusion after passing through a microaggrergrate filter (40 µm filter).Transfusion to be done within 6 hrs of collection.Volume not to exceed 1400 mlLow hematocrit valuePractised in cardiac surgeries and following knee arthroplasty.
56 Topical sealants: Fibrin Glue: Blood derivative Derived from a source of fibrinogen and factor Xlll (fibrinogen stabilizing factor)Applied directly to the site of bleed