Red Blood cells:
Structure
- 1 heme = 1 iron
- 1 hemoglobin = 4 iron
- 4 heme = 1 globin
- No nuclei, mitochondria or ribosomes
What do they do?
- Transport O2 to tissues, bring CO2 back
- Male: 4.5 – 6.3 million
- Female: 4.2 – 5.5 million
Lifespan
- 120 days (3 months)
- Reticulocyte à erythrocyte
- 24-36hrs à 36hrs – 120 days
Hemoglobin
- Red pigment that gives whole blood its color
- Male: 14-18 g/dL
- Female: 12-16 g/dL
- Oxyhemoglobin/deoxyhemoglobin
Hematocrit
- Percentage of RBCs in centrifuged whole blood
- Male: 40-54%
- Female: 37-47%
- (1:3 à hemoglobin: hematocrit)
,Anemia:
Causes
- Reduction in # of erythrocytes
- Impaired production (BMS, kidney problems)
- Blood loss (MVA, GSW, birth)
- Increase erythrocyte production (mismatched blood, end stage renal disease,
hemodialysis = destroyed RBCs
Definition
- Decreased erythrocytes
- Decreased hemoglobin
- Decreased hematocrit
Size Issues
- Microcytic hypochromic = small RBCs and decreased hematocrit
- Macrocytic = large RBCs (B12 and folic acid deficiency)
- Normocytic normochromic = normal size and hemoglobin… problem with
shape (sickle cell)
Iron Deficiency Anemia:
What is it?
- Microcytic hypochromic
Etiology
- Inadequate dietary intake, decrease absorption, increased demand
(pregnancy), increase loss)
Clinical Manifestations
- Pallor
- Glossitis
- Cheilitis
Evaluation
- Measurement of ferritin levels (Iron stores)
Treatment
- Identify source, iron replacement (PO, IV, IM), sodium gluconate
, - Usually continues 6-12 months AFTER bleeding stop s but may continue as
long as 24 months
- Diet!!!
Drug Therapy
à Oral iron (Ferrous sulfate) - Best absorbed on empty stomach (2 hrs before
meals, NO milk, drink with orange juice)
à Iron adverse effects - Constipation, N/V, cramps, black/ tarry stools
(expected), liquid iron can stain teeth! (Drink with straw)
à Parental Iron - Test dose 1st time then give if no reaction, may cause
orthostatic hypotension
1.) Ferric gluconate (safe for renal)
2.) Iron sucrose (venefor): hypotension, give large doses over 2.5-3.5
hours, sit upright for 15-30 min after oral iron to avoid esophageal
corrosion
Megaloblastic Anemia :
What is it?
- Large RBCs
- Results from deficiency on Vitamin B 12 (Cobalamin) and Folic acid
Pernicious Anemia (Vitamin B12 deficiency)***
- Most common megaloblastic anemia
- Lacks intrinsic factor (protein secreted by parietal cells in gastric mucosa (in
stomach)
- CANNOT absorb B12 without intrinsic factor
- Can give B12 shot to bypass the stomach
Clinical manifestations
- Weakness / fatigue
- Paresthesia’s of feet and fingers, difficulty walking (specific to B12
deficiency)
- NEUROLOGIC SYMPTOMS FROM NERVE DEMYELINATION B/C
VITAMIN B12 IS NEEDED FOR MYELINATION OF NERVES!!!
Diagnostics
- Blood tests
- Bone marrow aspiration, gastric biopsy (intrinsic factor)
Treatment
, - Weekly/monthly injections or high oral doses of vitamin B12 are
administered
- Teach to eat red meats, liver and eggs
Folic Acid Deficiency ***
- Megaloblastic anemia
Causes
- Dietary deficiencies (leafy greens, fish, veggies)
- Malabsorption syndromes (chrons, ulcerative colitis)
- Alcohol abuse
Treatment
• Folic acid with food
• Dosages decrease serum phenytoin levels by speeding up metabolism
of this drug (need to increase dose of phenytoin)
Hematopoietic Drugs
Contraindications
- Allergy
- >10% myeloid blasts
ADEs
- Fever
- Muscle aches
- Bone pain
- Flushing
- Interactions
• Antineoplastics that cause BMS
Treatment
à Filgrastim (Neupogen) – increases WBC count, given for non-myeloid
cancers when drugs will cause BMS, injection, discontinues if neutrophil
count is >10,000
à Sargramostim (Leukine) – given after bone marrow transplant, injection
à Oprelvekin (Neumega) – stimulates platelets in severe chemotherapy to
avoid platelet transfusion