Jehowah's witnesses and blood conservation strategies by Dr.Minnu M. Panditrao

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dr. Mrs. Minnu M. Panditrao explains the problems faced by anesthesiologists in anesthetising the Jehowah's Witness patients because of their beliefs. Ina ddition she also discribes various strategies of Blood conservation.

transcript

JEHOVAH’S WITNESSES AND

BLOOD CONSERVATION STRATEGIES

Dr. Mrs. Minnu M. PanditraoConsultant

Department of AnesthesiologyRand memorial; HospitalFreeport, Grand Bahama

The Bahamas

Formerly:

ProfessorDepartment of Anaesthesiology and critical care

Padmashree Dr. D. Y. Patil Medical CollegePimpri Pune.

Introduction

• Millenarian restorationist Christian denomination• Follow New World Translation of Holy Scriptures• Started in 1870’s as Bible Study Group in USA• IN 1931 adopted the name “Jehovah’s Witnesses”

• Presently >7 million are living all over the world

• en.wikipedia.org/wiki/Jehova’s_witnesses-

Introduction– Beliefs

• Door to door preaching ( Watchtower & Awake )

• Do not celebrate• Consider secular society – morally corrupt• Do not work in military services• Do not take un necessary risks with life• Do not kill/hurt animals for sport• Consider abortion and ART as wrong• Refuse transfusion of blood & its main components-

consider it violation of “God’s Law”

( Acts 15: 19-21 and Genesis 9: 3-4 )

Introduction

• Pose problems to treating doctors• Were mostly refused treatment due to their

adamant stand against blood transfusion• Nowadays trends are changing• They carry signed cards/ directives refusing

B.T. and absolving doctors of any liability

Introduction

• Do not accept— - whole blood - red blood cells - white blood cell - platelets - plasma

Introduction

• May accept fractions : - haemoglobin - albumin - immunoglobulins - interferons - cryoprecipitate etc.

Introduction

May accept treatments:• Haemodialysis• Plasmaphresis• Heart lung bypass circulation• Cell salvage & reinfusion

BLOOD CONSERVATION STRATEGIES

Very important to reduce blood loss to minimize the need for transfusion

Team work Multimodal approach,

combinations work synergistically

Blood Conservation Strategies in Surgical Patient

• Preparation of the patients prior to anticipated blood loss helps them to tolerate the blood loss to a greater extent

Pre-operative Preparation

Identification of factors that increase need for Blood Transfusion

• Pre operative anaemia• Coagulopathies• Malignancy• Renal failure• Cardiac/vascular diseases• Nature of surgical procedure

Pre-operative Preparation

Optimization of Haemoglobin Level• Hb < 10 gm% - Inv. & Tt anaemia, iron, vitamins & erythropoitin (weekly s/c injs) • Hb 10-13 gm% - oral iron, vitamin, erythropoitin• Hb 13-15 gm% - oral iron, vitamin supplements• Hb > 15 gm% - adequate red cell mass, low risk

• www.uwoanesthesa.ca/ac-perioperative.hmtl-

Pre-operative Preparation

• Screening and Optimization of Coagulation Profile

• Restricted Blood Sampling

Planning of Surgical/Anaesthetic Procedure

• Minimally Invasive Surgical Procedure• Extended Surgical Team• Use of Regional Anaesthesia

• www.transfusionontario.org/media

Intra-Operative Blood Conservation

Intervention By Anaesthesiologist• Acute Normovolemic Hemodilution• Haemostatic Agents• Positioning of the Patient• Hypotensive Anaesthesia• Maintenance of Normothermia• Optimum oxygenation & 02 delivery

• Minimising 02 demand

Acute Normovolemic Hemodilution

• Whole Blood is withdrawn from patient just before the surgery.

• It is replaced with a Crystalloid solution.• Blood is re-infused during and after surgery.• There is reduced loss of Red Blood Cells.• Reduces need for Allogenic Blood Transfusion.

Hemostatic Agents

• Anti-Fibrinolytic Agents• Desmopressin• Recombinant Factor VIIa (rFVIIa)• Somatostatin, conjugated oestrogens

• www.cmaj.ca/cgi/content/full/

Anti-Fibrinolytic Agents

Act against breakdown of clot.Aprotinin –

• Decreases the affinity of serine proteases.• Attenuates the inflammatory responses.• Decreases fibrinolysis.• Increases thrombin generation.

• Dose: 1-2 million kIU IV 250, 000 -500,000 kIU/hr• A/E- hypersensitivity, heart failure, stroke, renal

dysfunction.

Anti-fibrinolytic Agents

Lysine Analogues -- inhibit plasminogen by binding to lysine binding sites, inhibit deleter. effects of plasmin on platelets

• Tranexamic Acid: Dose 10 mg/kg IV, 1 mg/kg/hr• EACA: Dose 100-150 mg/kg IV, 25 mg/kg/hr• A/E- GI upset, thrombosis.

Desmopressin (DDAVP)

• Synthetic analogue of Arginine Vasopressin• Induces release of stored Factor VIII and von

Willebrand’s Factor from endothelial cells• Increases the platelet adhesiveness• Prevents/controls bleeding in haemophilics,

plalelet dysfunction • Dose: 0.3 µg/kg IV/SC/Intranasal

Recombinant Factor VIIa

• Vitamin K dependant glycoprotein• Helps in controlling bleeding in patients with

liver disease, factor VII deficiency, hemophiliacs, congenital platelet dysfunction, traumatic/surgical hemorrhage not responding to routine treatment

Mechanism of Action

• Binds to tissue factor → Activation of Factor X on platelet surface (F Xa).

• Factor Xa + Va → Prothrombin Complex → Thrombin Formation

• Dose: 15-180 µg/kg IVPlasma level: 50 nM/l – good for partial thrombin

releasePlasma level: 100-150 nM/l – full activation of

thrombin (Thrombin Burst)

Intra-Operative Blood Conservation

• Positioning of Patient -• Making Surgical Part higher than level of heart

reduces the blood loss.• Hypotensive Anaesthesia –

• Systolic BP: 80 – 90 mm Hg• Mean Arterial Pressure: 50 – 60 mm Hg

• Maintenance of Normothermia – • Better tissue Perfusion• Prevents Acidosis, Vasoparalysis, Coagulation Failure

Intra-Operative Blood Conservation

• Optimum oxygenation & 02 delivery

higher FiO2 in anaemic patients

prevention of hypovolemia,vasocontriction• Minimising 02 demand

controlled hypothermia (where appropriate) sedation, analgesia, muscle relaxation, mechanical ventilation

Surgical Techniques to Reduce Blood Loss

• Use of Tourniquet• Meticulous Hemostasis• Minimally Invasive Surgery• Laparoscopic/ Endoscopic Surgery• Arterial Embolization• Adrenaline Infiltration at Incision Site

Surgical Devices to Reduce Blood Loss

• Use of Electrocautry/ Electrosurgery• Argon Beam Coagulation• Laser Surgery• Stereotactic Laser Surgery• Gamma Knife Radiosurgery• Ultrasonic Scalpel• Microwave Coagulation Scalpel

Topical Agents To Control Bleeding

• Topical application of Vasoconstrictors• Surgical Adhesives-

• Fibrin Glue• Platelet Gel• Tissue Sealants

• Topical Packs, Sponges, Meshes, Tinctures and Special Dressings that promote Coagulation

Other Allogenic BT Alternatives

• Intra-operative Cell Salvage• Blood Substitutes

•Modified Hemoglobin• PerFluroCarbons

Intra-Operative Cell Salvage

• Shed Blood during Surgery/ Post-op period is collected, filtered and transferred in a anti-coagulant containing reservoir.

• It is re-infused with or without processing.• Processing-

• Centrifugally washed to remove debris and contaminants• Ultrafilteration, hemoconcentration

• Indications-• Cardiothoracic, Vascular and major Orthopedic

procedures, ruptured Ectopic pregnancy

Intra-Operative Cell Salvage

• Advantages• Decreased risk of Blood-borne Infections• Decreased Transfusion Reactions• Safe in Rare Blood Groups, Multiple Antibodies• No Immune Suppression

• Disadvantages• More Expensive• Increased Staff Training• Risk of Bacterial Contamination

Blood Substitutes

• These are Artificial Oxygen Carriers• Can Be used as alternatives to allogenic blood

in acute blood loss, or in critically ill patients• These are

• Modified Hemoglobins • PerFluroCarbons

Modified Hemoglobins

• These are either recombinant or derived from outdated RBCs (human or bovine)

• Advantages• No need of cross-matching• Long shelf life• Can be stored at room temperature• Decreased risk of disease transmission

Modified Hemoglobins

• Disadvantages• Short half-life after administration (24-48 hrs)• Increased Vascular tone and BP• Renal toxic effects• Interference with lab Hb measurements

• E.g. • Polyheme- From Human RBCs• Hemopure- From Bovine RBCs

• Safety and Efficacy not yet established.

PerFluroCarbons

• Trade Names- Oxygent, Oxycyte• Have the capacity to carry Oxygen and CO2 at a rate twice

that of Hemoglobin• Advantages-

• Long Shelf Life• No risk of Transmission of Blood-borne Diseases

• Disadvantage• Acute Lung Injury if used over long period as higher

concentration of Oxygen required• Safety and Efficacy needs further research investigation

PerFluroCarbons

Oxygent Oxycyte

Blood Conservation Strategies in Critically Ill Patients

• Proper Diagnosis and Treatment of Causative Factors of Anemia/ Blood Loss

• Reducing Blood Loss associated with diagnostic testing• Use of smaller volume collection tubes• Elimination of discarding of blood during collection from

indwelling catheter• Use of bedside microanalysis• Automated Closed Arterial Systems• Bedside monitoring of SPO2 , ETCO2

• Restricted Blood Sampling Frequency

Restricted Blood Transfusion Triggers

• Hemoglobin threshold of 7 gm% is safe and appropriate

• Allowable blood loss V = EBV x (Hct1- Hctf)/Hctav

• Use of erythropoietin, hematinics and nutritional support

• Use of hemostatic agents• Review of use of anti-coagulant/ anti-platelet

agents• Prompt correction of coagulopathies• Optimization of Oxygenation O2 delivery/demand• Use of artificial Oxygen carriers• Use of Hyperbaric Oxygen

Summarizing

• Jehovah’s witnesses are a sect of Christians who have an aversion for blood/components

• Blood conservation is essential in Jehovah’s witnesses

• Multimodal approach• Team work• Combination of strategies act synergistically

Conclusion

• No patient should be denied medical treatment because of their religious beliefs

• Blood conservation is practical• Should be extended to all the patients

because blood is a precious commodity & is not without thorns !

Thank you!