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Home , Apheresis, Blood product, Fluid replacement, Neutrophil

Basic Science

Jeremy Parsons MD Presbyterian Healthcare, Albuquerque, NM Confession

I am a museum tour guide for this topic. The curators in the back who know everything will be giving talks later throughout the meeting.

I may not know the answer to your questions off the top of my head. I do know where to find out.

I have no financial disclosures today. Barely scratching the surface today Outline

1) and 2)The and 3)Blood Component Therapy 4) Physiology 5)Common Clinical Laboratory Testing 6)Introduction to Hematology and Coagulation

 Historically blood was considered the essence of life.

 Hippocrates described 4 humors: blood, phlegm, black bile and yellow bile 400 BCE.

 Bloodletting was common to remove contamination and evil humors.

Breathing a Vein. James Gillray, published by H. Humphrey, St James’s Street, London, January 28, 1804.

Hematology and Coagulation

 Blood consists of multiple parts

 Plasma  Erythrocytes (RBC)  Leukocytes (WBC) 

Image courtesy of Fairview.org Plasma

 Liquid portion of blood

 Many substance dissolved or carried

 Proteins (albumin, globulins, etc.)

 Nutrients (, lipids, ammino acids)

 Gases (CO2, N)

 Metabolic waste (, )

(Na, K, Cl) Plasma Proteins

3 groups 1) fibrinogen / coagulation factors 2) albumin and small transport proteins 3) globulins Erythrocytes (RBCs)

Small biconcave discs

Hemoglobin for O2 transport

Carbonic anhydrase to convert CO2 to carbonic acid and bicarbonate

Erythrocytes produced in 2-3 million per second.

Red blood cells. Credit: Photos.com/Rice University

Erythrocytes

Average concentration of RBCs in blood is 4.5 - 6 x 106 cells/μl. Average life span of 120 days Leukocytes (WBCs)

Average total WBC count in 3.2-10 X 103 cells/μl Made up of 5 main types

 Neutrophils

Photo from Wikipedia Commons

Neutrophils 50-80% of WBCs Use to clear blood of and foreign particles Eosinophils 1-4% of WBCs Main defense against parasites Basophils <1% of WBCs Release inflammatory chemicals such as when activated by IgE. Mononuclear Cells

Lymphocytes 20-40% of WBCs B-cells involved with production T-cells involved with cellular

Monocytes 2-8% of WBCs Also phagocytic, circulate before migrating to tissues to become . Stem Cells

Normally localized to the bone marrow. Circulate in minute numbers in peripheral blood. Can be mobilized from marrow space into the peripheral blood (steroids, GCSF, plerixafor). CD34+ Platelets

Cellular fragments from Normal count 150-400 x 109/L. Average circulating time of 7-10 days Primary Bind to damaged of vessels via vWF Recruit other platelets to create a platelet plug

Photo from Wikipedia Commons Coagulation

Platelets are involved in primary hemostasis to create a temporary plug to seal vascular injuries

Secondary hemostasis involves plasma proteins in what is known as the coagulation cascade. Coagulation Cascade

3 pathways in the testing model Intrinsic (contact activation) aPTT Extrinsic ( factor pathway) PT Common

Factors I through 13 typically depicted by Roman numerals (factor IV is Calcium) (factor VI is actually activated V)

Immunity

1) Innate immunity: non-specific first response Physical and chemical barriers Phagocytic cells Compliment and 2) Acquired or adaptive: specific secondary response Lymphocytes Immunoglobulins ()

Acquired Immunity

T cells activated when presented with in association with MHC Important in self detection and cellular immunity HLA recognition

B cells form plasma cellss when stimulated by antigens Plasma cells secrete immunoglobuins Immunoglobulins

Antibodies to specific antigens 5 types IgA IgD IgE IgG IgM

Blood Groups

RBC membranes express membrane structures called antigens More than 20 can be clinically significant Play important role in transfusion, organ transplant, hemolytic disease of the newborn

RBC antigens ABO

Antigens expressed and plasma antibodies produced by each .

Photo courtesy of the University of Utah Genetics and Science Learning Center ABO Group Prevalence

ABO GROUP European Ethnicity African Ethnicity O 45% 49% A 40% 27% B 11% 20% AB 4% 4%

Adapted from Cooling L. ABO, H, and Lewis blood groups and structurally related antigens. Technical Manual 17th ed p. 364 RBC antigen antibodies

Antibodies to A and B RBC antigens are said to be naturally occurring as they are present soon after birth and do not require exposure to the RBC antigens. Other RBC antigens such as RH, Kell, Duffy and Kidd require exposure of the immune system Blood Component Therapy

Can be collected via donations or aphereis procedures. Most common types (1)Red blood cells (2)Plasma (3)Platelets (4) (5)Granulocytes Red Units

Stored at 1-6º C with shelf life up to 42 days in additive Will raise HCT 3-4% and Hgb approximately 1 g/dl Requires either serological or electronic crossmatch

Photo from Wikipedia Commons Plasma

FFP frozen to -18º C within 8 hours of collection FP24 frozen within 24 hours Usually used within 24 hours of thawing Cryoprecipitate-poor plasma is the byproduct of cryoprecipitate production. Used to help with by correcting coagulation factor deficiencies

Photo from Wikipedia Commons Platelets

Stored at room temperature (20-24º C) for up to 5 days Can be collected via whole or apheresis (5-6 whole blood platelets are approximately equal to 1 apheresis platelet unit) Expected to raise platelet count of 70-kg adult by 20-40k/μL Cryoprecipitate

Prepared by slowly thawing FFP at 1-6ºC The precipitate is separated and then refrozen for a 1 year shelf life Commonly pooled in groups of 5+. Contains fibrinogen, FVIII, FXIII, and vWF

Granulocytes

Collected by apheresis typically Stored at room temp for 24 hours Very rare therapy for special situations regarding bacterial or fungal in patient with low absolute neutrophil counts. Require irradiation to prevent TAGVFD

Photo from Wikipedia Commons

Blood Product Modifications

Irradiation: Use of radiation to inactivate donor lymphocytes to prevent transfusion associated graft vs host disease. : Use of filters to remove donor leukocytes from blood products. Leukoreduced blood units are deemed CMV safe. Washing: Removes plasma from units of RBCs. Used Primarily in IgA deficiency to prevent anaphylactic reactions. Electrolyte Physiology

Sodium Na primarily extracellular Normal serum range 135-147 mEq/L Plasma change does not change levels typically

Potassium K primarily intracellular Normal serum range 3.5-5.2 mEq/L 0.25 mEq/L decrease with albumin replacement 0.7 mEq/L decrease with plasma exchange.

Electrolyte Physiology

Chloride Cl primarily extracellular Normal serum range 95-107 mEq/L 4 mEq/L increase with albumin replacement 6 mEq/L increase with plasma exchange.

Bicarbonate HCO3 pH buffer of blood Normal Serum range 22-29 mEq/L 6 mEq/L drop with albumin replacement 3 mEq/L increase with plasma exchange.

Citrate

Used as in apheresis procedures Binds calcium to inhibit the coagulation cascade Acid Citrate Dextrose solution (ACD) ACD A 20.6-22.8 g citrate/ml ACD B 12.4-13.7 g citrate/ml

Calcium

Electrolyte most affected by apheresis. Most circulating calcium is bound to albumin Physiologically active ionized Ca is small fraction

Photo from Wikipedia Commons

Calcium

During apheresis ionized calcium decreased by three mechanisms. 1)removal of ionized Ca from plasma itself 2)binding of ionized calcium by citrate in the ACD solution 3)replacement fluid

 Albumin replacement binds calcium

 Plasma replacement introduces more citrate Hypocalcemia

Single plasma exchange using ACD infused at rates of 1.0-1.8 mg/kg/min will drop ionized Ca 25-35%

Some replace with oral calcium carbonate IV calcium gluconate or calcium chloride Common Lab Test for Apheresis

• CBC () • aPTT (activated partial thromboplastin time) • PT (prothrombin time) • Fibrinogen • LDH (lactate dehydrogenase) • Ionized calcium

Photo from Wikipedia Commons

Common Lab Test Cont.

• electrophoresis • Serum Viscosity • ADAMTS-13 (a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13)

• Specific analytes that are your target (antibody titers, IgM, etc.) Introduction to Apheresis Replacement Fluid Albumin • Typical 5% solution • Purified from pooled plasma • Maintains oncotic pressure • Lacks coagulation factors • Most commonly used

Photo from Wikipedia Commons

Replacement Fluids

Plasma • Has coagulation factors • Used when patient has underlying coagulopathy • Special case with TTP the plasma contains the ADAMTS-13 • Risk of ()

Photo from Wikipedia Commons

Replacement Fluid

Saline • 0.9% NaCl • 2 major uses • To reduce viscosity • Replace volume during cytoreductions

• Lacks oncotic pressure

Photo from Wikipedia Commons Replacement Fluid

Red Blood Cells • Red cell exchanges • • •

• Blood prime Review

Very basic overview barely scratched the surface.

Apheresis science is highly technical and well studied. My most active referring neurologist doesn’t ask me to remove antibodies from his patients. He asks for me to remove the bad humors from his patient. References

This presentation is an overview of the book chapter Parsons, Jeremy. (2014). Basic Science. In Walter Linz (Ed), Principles of Apheresis Technology 5th ed. (pp.1-22). Vancouver, BC: ASFA. All references for the chapter are in page 22 of text.

Apheresis Principles and Practice AABB Press Chopek M, McCullough J. Protein and biochemical changes during plasma exchange. In: Berkman EM, Umlas J, eds. Therapeutic hemapheresis. Washington, DC: AABB, 1980:13-52. Thanks

Walter Linz and Kendall Crookston for giving me the opportunity to work on this chapter.

My apheresis mentors Kendall Crookston @UNM Sara Koenig @UNM Leonor Fernando @UC Davis Questions?