WK 4: Sickle Cell Disease

Question 1

What are the 3 main causes of anemia

Answer 1

1. Blood loss
   
   2. Hypoproliferative
      ○ Impaired production of erythrocytes
      ○ Caused by iron, vitamin B12, or folate deficiency, decreased erythropoietin production, and cancer
   3. hemolytic
      ○ Increased destruction of erythrocytes
      Caused by altered erythropoiesis, or other causes such as drug-induced or autoimmune processes, inherited forms such as Sickle Cell

Question 2

Red blood cell function

Answer 2

· Transport oxygen (O2) from lungs to systemic tissues
· Carry carbon dioxide (CO2) from tissues to the lungs
· Because RBCs transport oxygen, erythrocyte disorders can lead to tissue hypoxia.
This hypoxia accounts for many of the signs and symptoms of anemia.

Question 3

What is hypoxia?

Answer 3

Hypoxia is a state in which oxygen is not available in sufficient amounts at the tissue level to maintain adequate homeostasis

Question 4

Clinical manifestations of Anemia

Answer 4

o Caused by the body’s response to tissue hypoxia
Hemoglobin (Hb) levels are used to determine the severity of anemia.

Question 5

What is erythrocytes

Answer 5

Red blood cell’s that its main function is to carry oxygen from the lungs and deliver it throughout our body.

Question 6

What is erythropoiesis?

Answer 6

Erythropoiesis is the development of mature red blood cells from erythropoietic stem cells

Question 7

What is sickle cell disease

Answer 7

· Severe hemolytic anemia from inheritance of sickle hemoglobin gene
· Autosomal recessive inheritance pattern
Sickle cell hemoglobin (HbS) is defective and changes the shape of RBC from a concave disk-shaped to a deformed, rigid sickle shape which adheres to endothelium off small vessels- impedes blood flow to region/organ

Question 8

Sickle cell disease risk factors

Answer 8

o HbS gene inherited in people of African descent, lesser extent Middle East, Mediterranean, aboriginal tribes from India
o Sickle cell trait refers to the carrier state for sickle cell disease and is the most benign type of SC disease- less than 50% of hemoglobin within the RBC is HbS
If 2 people with sickle cell trait have children, children may inherit 2 abnormal genes and will have sickle cell anemia

Question 9

Clinical presentation of Sickle Cell Disease

Answer 9

· Typical patient is asymptomatic, except during sickling episodes
· Symptoms and complications result from chronic hemolysis or thrombosis
· Sickled cells are rapidly hemolyzed- short life span of 10- 12 days
· Anemia is always present
· Jaundice is usually obvious in sclerae
· Bone marrow expands in childhood as compensatory effort- can lead to enlargement of bones in face and skull
Chronic anemia- tachycardia, cardiac murmurs, enlarged heart, dysrhythmias, heart failure

Question 10

Complications of sickle cell disease

Answer 10

· Sickling Episodes
○ Sickling episodes can affect any area of the body or several sites simultaneously, with the back, chest, extremities, and abdomen being most commonly affected.
○ Sickling episodes are most commonly triggered by low oxygen tension in the blood.
· Sickle cell crisis
○ Severe painful, acute exacerbation of sickling causes a vaso-occlusive crisis.
○ Results from tissue hypoxia and necrosis due to inadequate blood supply- Very painful
· Increased risk of infection
○ Pneumonia - most common infection
○ One reason that patients are susceptible to infection is a failure of the spleen to phagocytize foreign substances.
· Acute chest syndrome
Characterized by fever, chest pain, cough, pulmonary infiltrates, and dyspnea.

Question 11

Diagnostic studies used to evaluate sickle cell disease

Answer 11

o Peripheral blood smear
o Electrophoresis of hemoglobin
o Skeletal radiographs
o Magnetic resonance imaging (MRI)
o Doppler studies
Chest radiography

Question 12

Nursing management involved in sickle cell disease

Answer 12

· Patient teaching
○ Avoid high altitudes
○ maintain fluid intake
○ treat infections promptly
· Hydration
○ reduce blood viscosity and maintain renal function
· O2
○ For hypoxia and to control sickling
· Rest
○ reduce metabolic requirements
· Preventing/treating infections
immunizations, antibiotics

Question 13

Treatments used in Sickle Cell Disease: Transfusions

Answer 13

○ RBC transfusions highly effective in acute exacerbation of anemia
§ Prevention of complications from anesthesia and surgery
§ Improving response to infection
§ Severe cases of acute chest syndrome
§ Diminishing episodes of crisis in pregnant women
Preventing or managing complications from sickle cell disease

Question 14

Treatments used in Sickle Cell Disease: Folic Acid Supplements

Answer 14

○ Folic acid supplementation in SCD is based on the premise that chronic hemolysis leads to increased erythropoiesis which depletes folate stores.
○ It is hypothesized that folate supplementation may replenish these stores and thereby reduce the symptoms of anemia.

Question 15

Treatments used in Sickle Cell Disease: Hydroxyurea

Answer 15

Chemotherapy agent that decreases the formation of sickled cells

Question 16

Racism and sickle cell disease

Answer 16

Condition that affects your red blood cells. It’s more common in Black people, which is related to the evolution of the disease in parts of the world that have malaria.