Sickle Cell Disorder

Question 1

What is Sickle Cell Anemia?

Answer 1

A severe disease (Chronic). Hemolytic Anemia occuring in persons who are homozygous for the sickle cell gene.

Question 2

Etiology of sickle cell anemia

Answer 2

1. Sickle cell disease is genetically determined, inherited disease.
2. Each person inherits 1 gene from each parent, which governs synthesis of Hgb.

Question 3

Normal parent + Trait parent… What is to be passed on to offspring?

Answer 3

50% Normal
50% Trait
0% Disease

Question 4

Trait parent + trait parent. What is to be passed on to offspring?

Answer 4

25% Normal
50% Trait
25% DISEASE

Question 5

Trait parent + Disease parent. What is to be passed on to offspring?

Answer 5

0% Normal
50% Trait
50% Disease

Question 6

Disease parent + Disease parent. What is to be passed on to offspring?

Answer 6

100% Disease

Question 7

How is sickle cell anemia an inherited disease though?

Answer 7

1. In sickle cell, the animo acid sequence on the DNA chain is altered (replaced) with valine instead of glutamic acid on the 547th amino acid.
2. The 547th amino acid makes up the globulin fraction of Hgb.

Question 8

What does this Amino Acid change do to the Hgb in a sickle cell pt?

Answer 8

1. Hgb aggregates into elongated crystals under conditions of low O2 concentration, acidosis & dehydration.
2. Aggregation of Hgb molecules causes RBC to assume a crescent(sickle) shape.
3. This leads to traffic jamming to increased blood viscosity, vessel occlusion & last, tissue necrosis.

Question 9

How is this type of Anemia defined?

Answer 9

Anemia results when the rate of Destruction of RBC’s is greater than @ the rate of Production

Question 10

What are the clinical manifestations specific to sickle cell anemia?

Answer 10

1. Hgb 6–9
2. Loss of appetite
3. Pallor
4. Weakness
5. Fever–Due to dehydration, fluid in lungs(stasis)
6. Irritibility
7. Jaundice

Question 11

Sickle Cell Crisis

Answer 11

Small blood vessels are occluded by the sickle-shaped cells, causing DISTAL ischemia & infarction.

Question 12

Clinical Manifestation r/t Extremities

Answer 12

1. Bony destruction leading to osteoporosis

2. Bone pain; painful swollen large joints

Question 13

Clinical Manifestations r/t spleen

Answer 13

1. Abdominal pain
2. Slenomegaly – bc of RBC sequestation (Pulling & holding onto RBC)
3. Decreased splenic function increases risk of infection (Most common death in elderly)

Question 14

Clinical Manifestations r/t CNS

Answer 14

1. CVA
2. Hemiplegia (paralysis of the arm, leg, and trunk on the same side of the body.)
3. Retinal damage leading to blindness
4. Seizures

Question 15

Other Manifestations in other organs include:

Answer 15

1. Pulmonary Infarction
2. Altered Renal Function
3. Impaired Liver Function

Question 16

Altered Renal Function r/t Sickle Cell Crisis:

Answer 16

1. Decreased urine output <30/hr
2. Electrolyte imbalance
3. Check creatinine lab/BUN as well

Question 17

Impaired Liver Function r/t Sickle Cell Crisis:

Answer 17

1. Increased liver enzymes
2. Jaundice
3. Peripheral edema
4. Albumin pulls smaller molecules (H2O) to itself into intravascular space (3rd spacing)
5. Iscites – Fluid accumulation
6. Abdominal distention

Question 18

What Causes a Sickle Cell Crisis?

Answer 18

1. Dehydration
2. Infection
3. Trauma
4. Strenuous physical exertion
5. Extreme Fatigue
6. Cold Exposure
7. Hypoxia
8. Acidosis
9. Acidosis
10. Surgery
11. Pregnancy

Question 19

What Will My Assessment Look Like?

Answer 19

1. Hx: Possible dehydration, hypoxia, infection or other precipitating events
2. Observe for: Pallor, jaundice, changes in vs(Increased Temp, tachycardia, hypotension, tachypnea) Changes in mental status, edema, ulcers, lesions.
3. Examine for: Enlarged liver/Spleen, tenderness of hands/feet.
4. Hx & characerization of pain

Question 20

What are some diagnostics to perform for Sickle Cell?

Answer 20

1. Sickling test: O2 removed from blood & observed for sickling
2. Sickledex: p collection, sickle Hgb indicated if solution turns cloudy
3. Hgb Electrophoresis: Dx trait & disease
4. Antenatal Dx: