Blood Conservation

Perioperative Blood Conservation – An Overview

Dr Prashant Shanker Agarwal

Dr Ashok Jadon

Deptt. Of Anaesthesiology

Do we feel that a transfusion is an organ transplant ?

Session Objectives

• Provide an overview of blood conservation in perioperative patients

What is it?..Why is it important?..How is it accomplished?..

SABM, 2007

What is Blood Conservation?• Blood Conservation: Society for

the Advancement of Blood Management (SABM)

‘team approach to surgical patient care that utilizes the latest drugs, technology and techniques to enhance a patients own blood supply and decrease blood loss …the aim is to reduce or avoid the need for transfusion’

Why do we need blood…?

• For O2 transport…?

• O2 Content =

Hb*1.37*SaO2 + 0.0034*PaO2

• At Hb 4.7 g/dl O2 delivery reduces by 30% (Liberman JA. Anesthesiology 2000; 92.)

• Upto 40% permissible loss( approximately 2L in males) (Herbert PC. NEJM 1999; 340)

ASA task force guidelines 1996

• Transfusion is rarely indicated when the hemoglobin level is above 10 g/dL

• Almost always indicated in patients when the hemoglobin level is below 6 g/dL;

• For hemoglobin level 6-10 g/dL – Ongoing indication of organ ischemia, – The rate and magnitude of any potential or actual

bleeding,– The patient’s intravascular volume status – Risk of complications due to inadequate oxygenation.

• Use Blood Components separately• Promote blood conservation

O'Brien et al , 2007

Infectious and Non Infectious risks • 1 in 100 – minor allergic reactions

– rash etc

• 1 in 300 – febrile non-hemolytic reaction to RBC

• 1 in 700 – transfusion related circulatory overload

• 1 in 5,000 – Transfusion Related Acute Lung Injury (TRALI)

• 1 in 10,000 – Symptomatic bacterial sepsis from platelet transfusion

• 1 in 40,000 – death from bacterial sepsis - platelet transfusion

• 1 in 40,000 – ABO incompatible transfusion per RBC transfusion

• Coagulopathy

•1 in 40,000 – serious allergic reaction per unit of component, anaphylaxis

•1 in 82,000 – transmission of Hep B virus

•1 in 100,000 – bacterial sepsis per unit of RBC

•1 in 500,000 – death from bacterial sepsis per unit of RBC

•1 in 1,000,000 – WNV

•1 in 2,300,000 – Hep C transmission

•1 in 7,800,000 – HIV transmission

•Post Transfusion Purpura

Intraoperative RBC Tx Increases Risk of Low

Output Failure

Surgenor, et al. Circulation 2006;114:43-48

Is Blood Transfusion safe…when you can prevent it?

• Patient safety• Informed choice for patients

• Resource allocation• Infectious risks

• Non-infectious risks• Blood products are a scarce

resource• Blood is expensive!

Blood Conservation – Why?• Conserve blood resources

– Regional blood centers find it increasingly difficult to collect sufficient blood to meet patient needs in many areas of the country.

– In the next 15-20 years the number of patients >65 y.o. will more than double but the number of blood donors will only marginally increase

– The number of units used nationwide is increasing 1% per year, but the people donating is decreasing 1% per year.

Blood Component

Therapy

Blood Conservation… Why perioperative patients?

• 50-70% of blood products used in hospitals are used in the perioperative setting (Hebert et al, 2004)

• Potential exists to modify some predictors of transfusion in elective surgical patients

- Pre-op Hb, Blood loss

• Wide variation in transfusion practice for procedures

How important is pre-op Hemoglobin?

• A national (US) audit found that 35% of patients coming for arthroplasty have Hb <130g/L

• UK study found that 20% of all patients in 1 year were anemic males<130g/L, females <115g/L)

•GoodenoughGoodenough, , 20072007

•Karkouti et al 1999Karkouti et al 1999

•Saleh et al, 2007Saleh et al, 2007

How Blood Conservation accomplished?

• Preoperative evaluation & Risk stratification

• Reduce need for blood transfusion

• Autologous Transfusion

Pre-op evaluation

Pre-op Hb optimization: 4-6 week lead time for assessment, screening and

appropriate interventions:• Correction of nutritional anemia

iron therapy – dietary advice,supplements Vit B12, Folate

• Careful attention to patient medical history, pre op meds

ASA, Clopidrogel (Plavix), NSAIDs, herbal supplements

• Pre operative autologous donation• Erythropoietin therapy (Karkouti et al, 2005)

• ? Delay surgery

METHOD TO REDUCE BLOOD USE IN SURGERY

• PREOPERATIVE * Surgery elective – Correct the Haemoglobin level. Stop drugs that interfere

haemostasis.• INTRAOPERATIVE

– Posture– Use of Vasoconstrictors– Use of tourniquets– Use of anti-fibrinolytic drugs eg tranexamic acid– Use of Aprotinine– Controlled hypotension, Regional anaesthesia

• POST OPERATIVELY– Blood can be salvaged from drains into collection

devices that permit reinfusion

Meticulous Technique

• Careful, precise procedures, using natural tissue planes

• Planned vascular control• Use of clips, ligatures, and cautery

where appropriate• Newer techniques (harmonic scalpel,

LASER)• NB. MINIMIZE BLOOD LOSS

Volume Expanders

• ACUTE VOLUME REPLACEMENT

• HYDROXYETHYL STARCH (HES)

• DEXRAN 70

• DEXTRAN40

• UREA-BRIDGED GELATIN (HAEMACCEL)

• Blood substitutes

Blood Substitutes

• Hb sol. (human, bovine) – • Increases Hct• systemic & pulmonary HTN

• Perflurocarbon emulsions –• O2 solubility 20 times of plasma• Decreases Platelets & require high PaO2

• Focus is on the ability to carry oxygen, not on the other functions of blood

• Effective only for 12-24 hrs• Good for short term till blood is arranged

Cell Salvage With Ultrafiltration

• ‘recycling’ of blood that would otherwise be discarded

• CV/ortho/trauma (Cochrane, 2006)

• Contraindicated in malignancy, contaminated wound

• RBC’s suspended in NS• May be acceptable to

JW patient

Cell Saver

Cell Salvage

• The Hemobag® and its TS3 tubing set allows for Ultrafiltration both during the case and at the end for Whole Blood Autotransfusion.

• The end product is a hyperoncotic Autologous Whole Blood packed with viably functioning Platelets, Clotting Factors, Albumin, Plasma Proteins and RBC’s with no morbidity or side effects.

Isovolemic Haemodilution

• 1 to 2 units of patient’s blood withdrawn at the beginning of a procedure

• Blood volume restored with crystalloid/colloid solution

• Patient bleeds “thin blood” during procedure

• Gets own blood back at the end

Autologous Blood Transfusion

Collection and re-infusion (transfusion) of the patient’s own

Blood or Blood components.

Why Autologous Blood Transfusion

• Fully compatible blood.• No risk of transfusion transmitted diseases

such as hepatitis, CMV and HIV infection.• Avoidance of allo-immunization.• Improved O2 perfusion by lowering blood

viscosity.• Acute Normovolemic Hemodilution provides

fresh whole blood .• Less dependant on the blood bank’s stock.

A marked reduction in the hospital infection rates, antibiotic usage and length of hospital stay in patients who received autologous blood or no blood

Triulzi et al, Transfusion 1992;32:517-524; Forgie et al, 1998

Why Autologous Blood Transfusion

•Readily available in major haemorrhage•Avoidance of immuno-suppression

Criteria

• Age: less than 65 year old• Hb: at least 11.0g/dl• Weight: at least 50kg• No h/o severe heart and lung disease,

abnormal bleeding tendency • No bacteraemia at time of donation• No h/o hepatitis B/C or HIV• Cancer not a contraindication

Pre-surgical Autologous Blood Donation

• Best choice for patients with rare blood types or irregular antibodies.

• One unit per week & takes Fe/EPO.• Then donates 1 unit per week (usually no more

than 3 or 4 units)• Last donation must be at least 72 hrs before

operation.• Blood is stored and kept for patient for re-

infusion during/after operation.

Labeling and Storage

• Carefully designed system.

– Special procedure code

– Autologous stamp.

– Detail of place and date of operation.

• Special and distinct label on blood pack.

• Autologous donor card with unit number on it.

• Stored in different site.

Should Autologous Blood be “made homologous”?

The American Medical Association, AABB, NBS discourage the “crossover” of unused autologous units to the general blood supply.

• Liberal eligibility criteria. • Safety concerns.• Legal liability

Role of Erythropoietin in Autologous Transfusion

• Allow more units to be collected.

• Need two to more weeks to work.

• Expensive.

Points to consider

• Cost

• Surgeon and Anaesthetist enthusiasm

• Availability of allogeneic blood

• Which types of procedures: “ortho; intestinal; clean operations”

• Public awareness

• Remember that transfusion of any Allogeneic blood or blood products is an “Organ Transplant", and not just another medication that is without side-effects. Treat everyone like a JW !

End of starting…..

Transfusion Algorithm

• Avoid Transfusion : medical and surgical

• Alternatives

replacement fluids: crystalloids and non plasma colloids over plasma

pharmacologic agents to reduce bleeding

• Autologous donation• Minimize exposure to allogeneic

transfusion

Thought for the day……“Blood transfusion is a lot like

marriage. It should not be entered into lightly, unadvisedly or wantonly, or more often than is absolutely necessary.”

Beal, RW, 1976Beal, RW, 1976

Beal RW, 1976Beal RW, 1976

THANK YOUTHANK YOU

Tranexamic Acid• Mechanism of Action:• Forms a reversible complex that displaces plasminogen from fibrin resulting

in inhibition of fibrinolysis; it also inhibits the proteolytic activity of plasmin

• Dose Children and Adults: I.V.: 10 mg/kg immediately before surgery, then 25 mg/kg/dose orally 3-4 times/day for 2-8 days

• Dosage modification required in patients with renal impairment; ophthalmic exam before and during therapy required if patient is treated beyond several days; caution in patients with cardiovascular, renal, or cerebrovascular disease; caution in patients with a history of thromboembolic disease (may increase risk of thrombosis); when used for subarachnoid hemorrhage, ischemic complications may occur

• Adverse Reactions:• >10%: Gastrointestinal: Nausea, diarrhea, vomiting • 1% to 10%: Cardiovascular: Hypotension, thrombosis • Ocular: Blurred vision • <1%: Unusual menstrual discomfort • Postmarketing and/or case reports: Deep venous thrombosis (DVT),

pulmonary embolus (PE), renal cortical necrosis, retinal artery obstruction, retinal vein obstruction, ureteral obstruction

Summary• Controlled Hypotensive Anaesthesia

– current perspective

• Cell savaging procedures !!!!...???

• Use of Regional Anaesthesia & Tranexamic Acid

• Autologus Hemotransfusion– Normovolemic Hemodilution

• Increase oxygen delivery• Decreased DVT

»Thank You