Hematologic Function

➢ Anatomy and Physiology

➢ Assessment
➢ Diagnostic evaluation
➢ Treatment Modalities

HEMATOLOGY
- The study of blood and blood-forming tissues. this includes
bone marrow, blood, spleen, & lymph system.

-------------ANATOMY AND PHYSIOLOGY--------------

Consists of the:
• Blood
• Blood Production Sites
✓ Bone marrow
✓ Reticuloendothelial system (RES)

→ Site of hematopoiesis (blood cell formation).

→ The soft material that fills the central core of bones.
→ A specialized organ; considered as a liquid organ.
Stimulated by ERYTHROPOIETIN → A type of connective tissue.
→ Adult total blood volume: 4.7 and 5.5 L (5 to 6 quarts).
Stem cell differentiation
3 MAJOR FUNCTIONS
2 TYPES OF BONE MARROW • Transportation
✓ O2 from lungs to cells.
• Yellow bone marrow (adipose)
✓ Nutrients from GI tract to cells.
• Red bone marrow
✓ Hormones from endocrine glands to tissues a& cells.
Red bone marrow ✓ Metabolic waste products (CO2, NH3, urea) from
- Hematopoietic; actively produces blood cells. cells to lungs, liver, and kidneys.
- Found primarily in the flat and irregular bones.
• Regulation
✓ Fluid and electrolyte balance.
✓ Acid-base balance.
✓ Body temperature.
✓ Maintaining intravascular oncotic pressure.

• Protection
✓ Maintaining homeostasis of blood coagulation.
✓ Combating invasion of pathogens and other foreign
substances.

2 MAJOR COMPONENTS
• Plasma
• Blood cells

→ Makes up approx. 7-9% of the normal body weight.

→ Amounts to:
• 5-6 L of volume for men
• 4-5 L for women
→ About 45% of the blood.
→ Composed of formed elements (blood cells).

3 TYPES OF BLOOD CELLS

Red blood cells (RBCs)
- Oxygen transportation.
White blood cells (WBCs)
- Immune function.
Platelets
- Oxygen transportation.
 CELL TYPE MAJOR FUNCTION
WBC (Leukocyte) Fights infection.
Neutrophil Essential in preventing or limiting
bacterial infection via phagocytosis.
Monocyte Enters tissue as macrophage; highly → Normal: Enucleated, biconcave disc. No nuclei.
phagocytic, especially against fungus; → Hemoglobin contains iron and protein (for oxygen
immune surveillance. transport).
→ Principal function is to transport of oxygen between the
Eosinophil Involved in allergic reactions lungs and tissues.
(neutralizes histamine); digests foreign
→ Reticulocytes (immature of RBCs).
proteins.
Lymphocyte Integral component of immune system. WHOLE BLOOD
- Contains 14-15 g of hemoglobin per 100 mL of blood.
- Circulate about 115 to 130 days before elimination by
T lymphocyte Responsible for cell-mediated
immunity; recognizes material as reticuloendothelial system, primarily in spleen and liver.
“foreign” (surveillance system
B lymphocyte Responsible for humoral immunity;
many mature into plasma cells to form
antibodies.
Plasma cell Secretes immunoglobulin (antibody);
most mature form of B lymphocyte.

RBC Carries hemoglobin to provide oxygen

(Erythrocyte) to tissues; average lifespan is 120 days.

Platelet Fragment of megakaryocyte; provides

(Thrombocyte) basis for coagulation to occur; maintains
hemostasis; average lifespan is 10 days.

→ Primitive cells.
→ Have the ability to self-replicate.
→ When stimulated, it undergoes differentiation.

Self-replicate

Thereby ensuring a continuous supply of stem cells

throughout the life cycle.
DIFFERENTIATION PROCESS → Entire process of erythropoiesis occurs over 1 week.
Stem cells BONE MARROW

Myeloid or lymphoid stem cells Primitive myeloid stem cells

These stem cells are committed to Reticulocyte

produce specific types of blood cells. (immature nucleated cell that gradually loses its nucleus)
 DIFFERENTIATION PROCESS VITAMN B12 & VITAMIN B9 (FOLATE) METABOLISM
• Required for the synthesis of deoxyribonucleic acid
- Stimulated by erythropoietin [EPO], a hormone produced
(DNA) in RBCs.
primarily by the kidney.
Synthesis:
Increased EPO (due to anemia) ▪ Vitamin B12 combines with intrinsic factor produced in
the stomach which becomes vitamin B12–intrinsic factor
complex.
Stimulates the bone marrow
Absorption sites:
Increased production of erythrocytes ▪ Folate – proximal small intestine.
▪ Vitamin B12-intrinsic factor complex – distal ileum.

Food sources of folate:

▪ Beans and legumes
▪ Citrus fruits and juices
▪ Whole grains
▪ Dark green leafy vegetables
▪ Poultry
▪ Pork
▪ Shellfish
▪ Liver

IRON STORES AND METABOLISM

• Regulated by the amount of iron already stored in the body
and by the rate of erythrocyte production.
✓ Pregnant women (30 mg of iron daily)
✓ Adult men (12 mg of iron daily)
✓ Children (10 mg of iron daily)

Iron is stored as ferritin

Released into the plasma

→ Average lifespan of a normal circulating erythrocyte is 120
DAYS.
Increased production of erythrocytes
Old erythrocyte loses elasticity
• Excretion of iron: through feces (either in bile, blood, or
mucosal cells from the intestine). Become trapped in small blood vessels and the spleen
• Normal value (iron blood concentration): 50 to 250 µg/dL.
• Vitamin C (to enhance absorption).
Removed from the blood by the reticuloendothelial cells
(liver and the spleen)
Sole cause of iron deficiency in adults
- lack of dietary iron. Hemoglobin is recycled

Bilirubin is secreted in the bile

Iron is recycled to form new hemoglobin molecules within

the bone marrow (small amounts are lost daily in the feces
and urine and monthly in menstrual flow).

→ Not technically cells; they are granular fragments of giant

cells in the bone marrow called megakaryocytes.

Functions:

Circulates in an inactive state

Nurtures the endothelium of the blood vessels

Maintaining the integrity of the vessel

▪ Vascular injury occurs, platelets collect at the site and are

activated.
Thrombopoietin (hormone)
- Which stimulates the production and differentiation of
megakaryocytes from the myeloid stem cell in the marrow.

• Primary Hemostasis
• Secondary Hemostasis
• Coagulation Cascade

→ The remaining liquid portion of the blood after cellular

elements are removed.
→ If plasma is allowed to clot, the remaining fluid is called
SERUM.

→ Consist primarily of albumin and globulins.

Albumin: ________________________________________
 SKIN
Findings Potential Indications
GRAY-TAN OR BRONZE Hemochromatosis
SKIN COLOR (primary or secondary)
(especially genitalia, scars,
exposed areas)

-------------------------ASSESSMENT-------------------------
SKIN
Findings Potential Indications
RUDDY COMPLEXION Polycythemia
Family History Assessment Specific to Hematologic Disorders (face, conjunctiva, hands, feet)
• Maternal and paternal relatives from three generations of
the family.
• Blood disorders or episodes of abnormal bleeding.

If a family history or personal risk is suspected:

• Screening for bleeding disorders prior to surgical
procedures.

HEMATOLOGIC DISORDERS
- Are marked by aberrations in the structure or function of
the blood cells or the blood clotting mechanism.

Autosomal Dominant:
• Factor V Leiden SKIN
• Familial hypercholesterolemia Findings Potential Indications
• Hereditary angioedema PETECHIAE Severe thrombocytopenia
(pinpoint hemorrhagic lesions,
• Hereditary spherocytosis
usually more prominent on
• Von Willebrand disease
trunk or anterior aspects of
lower extremities)
Autosomal Recessive:
ECCHYMOSES Thrombocytopenia,
• Hemochromatosis
Coagulopathy
• Sickle cell disease
• Thalassemia

X-Linked:
• Hemophilia
SKIN RESPIRATORY
Findings Potential Indications Findings Potential Indications
RASH If pruritic, may indicate Increased rate and depth of Anemia; Infection
polycythemia. respirations; presence of
BLEEDING Thrombocytopenia, adventitious breath sound
(including around the vascular Coagulopathy
lines, tubes)
CONJUNCTIVAL Severe thrombocytopenia, CARDIOVASCULAR
HEMORRHAGE Coagulopathy Findings Potential Indications
Distended neck veins, edema, Severe anemia;
chest pain on exertion, Polycythemia
murmurs, gallops

Hypotension (below baseline)

Hypertension (above baseline)

GENITOURINARY
Findings Potential Indications
Hematuria Hemolysis;
SKIN Thrombocytopenia
Findings Potential Indications
PALLOR Anemia
MUSCULOSKELETAL
(in mucous membranes,
Findings Potential Indications
conjunctiva, nail beds)
Pain/swelling in knees, wrists, Hemophilia;
JAUNDICE Hemolysis
hands Sickle cell disease
(in mucous membranes,
conjunctiva, nail beds, palate)
ABDOMINAL
Findings Potential Indications
Stool positive for occult blood Anemia;
Thrombocytopenia

ABDOMINAL
Findings Potential Indications
PNS/CNS Dysfunction Vitamin 12 deficiency
(sensory)
Visual changes, headache, Severe thrombocytopenia
ORAL CAVITY alteration in mental status
Findings Potential Indications
SMOOTH Pernicious anemia
(tongue) GYNECOLOGIC
BEEFY RED Vitamin B12/ or folate Findings Potential Indications
(tongue) deficiency Menorrhagia Thrombocytopenia;
ENLARGED TONGUE Amyloidosis Coagulopathy

GENERAL
Findings Potential Indications
Fever, chills, sweats, asthenia Leukemia; Lymphoma;
Infection

----------------DIAGNOSTIC EVALUATION---------------

ORAL CAVITY
Findings Potential Indications COMPLETE BLOOD COUNT (CBC)
ANGULAR CHEILOSIS Anemia • Obtained via venipuncture.
(ulceration at the corners of • Identifies the following:
the mouth) ✓ Total number of cells (leukocytes, erythrocytes
ENLARGED GUMS; Leukemia and platelets).
HYPERPLASIA ✓ Hemoglobin
PETECHIAE Severe thrombocytopenia ✓ Hematocrit (percentage of blood volume
(buccal, mucosa, gingiva, hard consisting of erythrocytes)
palate) ✓ RBC indices

PERIPHERAL BLOOD SMEAR

• A drop of blood is spread on a glass slide, stained, and
examined under a microscope.
• Indication: cellular morphology (shape and appearance of
the cells).
 LOCATION OF ASPIRATION
• Adult: iliac crest; sternum (occasionally).

PRODECURE (BONE MARROW ASPIRATION)

• Bone marrow needle is introduced with a stylet in place.

Needle

Outer cortex of the bone

Enters the marrow cavity

Stylet is removed

A. Prothrombin Time (PT) Syringe is attached

▪ Typically replaced by the standardized test called
international normalized ratio (INR).
▪ Evaluates ability to clot. Aspiration of small volume (5 mL) of blood and marrow.

B. International Normalized Ratio (INR) CAUTION

▪ Ensures that results from a PT test are the same from one • Actual aspiration always causes sharp but brief pain,
lab to another. resulting from the suction exerted as the marrow is
aspirated into the syringe (use comfort measures and/or
C. Activated Partial Thromboplastin Time (APTT) relaxation techniques).
▪ Determines if blood-thinning therapy is effective.

INDICATIONS
• Evaluating a patient’s clotting ability.
• Monitoring the therapeutic effectiveness of anticoagulant
medications.

PROCEDURE
• In both tests, specific reagents are mixed into the plasma
sample, and the time taken to form a clot is measured.

PURPOSE
• To assess how a patient’s blood cells are being formed.
• To assess the quantity and quality of each type of cell
produced within the marrow.
• To document infection or tumor within the marrow.

BONE MARROW EXAM

- Bone marrow biopsy + bone marrow aspiration.

PATIENT PREPARATION
• Signed informed consent.
• Skin (site) preparation.
• Anxiolytic agent (for anxious patients).
• Administration of local anesthetic agent (skin & subQ to
the periosteum of the bone → it is not possible to
anesthetize the bone itself).

NORMAL (BONE MARROW ASPIRATE)

- Semifluid state.
- Can be aspirated through a special large needle.
PURPOSE OF BONE MARROW BIOPSY -----------------TREATMENT MODALITES----------------
• When more information is need; further test from
aspiration.
• Examines a solid part of the bone marrow. → Surgical removal of the spleen (laparoscopic) § removes the
• Shows the architecture of the bone marrow as well as its “trap,” and platelet counts to normal.
degree of cellularity.
INDICATIONS
LOCATION OF BIOPSY • Enlarged spleen (may be a site of excessive destruction of
• Posterior iliac crest; anterior approach (occasionally) blood cells).

PRODECURE (BONE MARROW BIOPSY) Enlarged spleen

• Special biopsy needle is used (large needle).
Develops severe thrombocytopenia
Skin may be punctured first with a surgical blade to make a (due to platelets being sequestered in the spleen)
3- to 4-mm incision
RISKS
Advanced into the marrow cavity • Hemorrhage
• Increased clotting
A portion of marrow is cored out • Injury to surrounding organs and tissues

The marrow sample is obtained

→ Apheresis is a Greek word meaning “separation”.

Pressure is applied to the site for several minutes Blood is taken from the patient, passed through a centrifuge

Site is then covered with a sterile dressing. A specific component is separated from the blood

Removed and the remaining blood is returned to the patient

→ To remove platelets.
→ Examples of Clinical Use
• Extreme thrombocytosis, essential
thrombocythemia (temporary measure)
• Single-donor platelet transfusion

→ To remove WBCs (can be specific to neutrophils or

lymphocytes).
→ Examples of Clinical Use
• Extreme leukocytosis (e.g., AML, CML) (very
temporary measure)
• Harvest WBCs for transfusion

→ To remove RBCs.
→ Examples of Clinical Use
• RBC dyscrasias (e.g., sickle cell disease)
• RBCs replaced via transfusion

→ To remove plasma proteins.

→ Examples of Clinical Use
• Hyper-viscosity syndromes
• Renal and neurologic diseases (Goodpasture
syndrome, TTP, Guillain-Barr, myasthenia gravis)

→ To remove circulating stem cells.

POST-BIOPSY NURSING CARE → Examples of Clinical Use
• Discomfort (ache) • Transplantation (donor harvest or autologous).
✓ Warm tub baths
✓ A mild analgesic agent (acetaminophen)
✓ Avoid: Aspirin-containing analgesic agents → May be transplanted from either allogeneic or autologous
✓ No rigorous activity or exercise for 1 to 2 days donors.
→ For hematologic disorders: allogeneic transplant (effective)
COMPLICATIONS FOR A BONE MARROW EXAM
• Bleeding & infection
 ALLOGENIC • Donors must wait at least 8 weeks between whole blood
(standard) donations.
- From a matched donor’s stem cells.
• People younger than 17 years require parental consent in
AUTOLOGOUS
some states.
- From the patient’s own stem cells.
• The oral temperature should not exceed 37.5°C (99.6°F).
• The systolic arterial blood pressure should be 80 to 180
mm Hg, and the diastolic pressure should be 50 to 100 mm
Hg.
• The hemoglobin level should be at least 12.5 g/dL.
• Prospective donors who received a blood transfusion must
wait 12 months before a donation is accepted.
• Men who have sexual relations with men must wait 3
months from their last sexual encounter before a donation
is accepted.

• Directed Donation (_____________________________).

• Standard Donation (_____________________________).
• Autologous Donation (__________________________).
• Intraoperative Blood Salvage (____________________).
• Hemodilution (_________________________________).

✓ Laceration of the vein.

→ The removal of a certain amount of blood under controlled ✓ Excessive tourniquet pressure.
conditions. ✓ Failure to apply enough pressure after the needle is
withdrawn.
→ Example: Polycythemia vera ( Hct)
• Managed by periodically removing 1 unit (about 500
mL) of whole blood.
→ Due to emotional factors, a vasovagal reaction, or prolonged
fasting before donation.
--------------BLOOD & BLOOD PRODUCTS -------------- → Because of the loss of blood volume, hypotension and
syncope may occur when the donor assumes an erect
position.
→ Single unit of whole blood contains: 500mL
→ A donor who appears pale or complains of faintness should
• _______ mL of blood immediately lie down or sit with the head lowered below the
• _______ mL of an anticoagulant knees – observe for 30 minutes.
→ Primary Components
• Erythrocytes
• Platelets
• Plasma
• Leukocytes (rarely used)

→ Stored at 4°C (39.2°F); storage life: 42 days.

→ Room temperature (can’t withstand cold temperature.

→ Storage life: 5 days
→ To prevent clumping, platelets are gently agitated while
stored.
→ Crossmatching is a way for your healthcare provider to test
your blood against a donor's blood to make sure they are
→ Immediately frozen to maintain the activity of the clotting fully compatible.
factors within. → It's essentially a trial transfusion done in test tubes to see
→ It lasts for 1 year if it remains frozen. exactly how your blood will react with potential donor
→ Plasma can be further pooled and processed into blood blood.
→ derivatives (such as albumin, immune globulin, factor VIII, → Crossmatching is a test used to check for harmful
and factor IX). interactions between your blood and specific donor blood or
organs.
→ It can help your doctor predict how your body will react to
• Factor VIII concentrate (antihemophilic factor) those donor materials.
• Factor IX concentrate (prothrombin complex)
• Plasma albumin – helps oncotic pressure
• Immune globulin – concentrated solution of the antibody → ABO SYSTEM identifies which sugars are present on the
immunoglobulin G (IgG); Intravenous immunoglobulin membrane of a person’s erythrocytes:
(IVIG). ✓ Type A
✓ Type B
✓ Type AB (both A & B)
MINMINAL REQUIREMENTS: DONOR ✓ Type O (neither A nor B)
• Body weight should be at least 50 kg (110 lb) for a
standard 450-mL donation.
→ Rh antigen (also referred to as D).
→ Is present on the surface of erythrocytes in 85% of the
population Rh positive.
→ Those who lack the D antigen are referred to as being Rh
negative.
→ The “Rh factor” was named this because it was first
identified in rhesus monkeys.