Sickle Cell Anemia Flashcards
Normal type of hemoglobin
Hemoglobin A
Abnormal type of hemoglobin in sickle cell anemia
hemoglobin S
This is where a person has abnormal hemoglobin S (normal hemoglobin is hemoglobin A) on their red blood cell.
Sickle Cell Anemia
This type of hemoglobin is very sensitive to oxygen changes, which causes the red blood cell to change it’s shape. This can lead to many complications (sickle cell crisis).
what to remember about hemoglobin S
it is very sensitive to low O2 in the body. anything that causes the body to increase its demand for oxygen, like higher altitude, dehydration or infection, will cause the red blood cells then to change their shape, to become sickle shaped. They will be stiff and sticky. They will block blood flow into tissues. Patient can enter into sickle cell crisis
sickle shaped RBC live span
tend to rupture and break down at about 20 days. this is where the anemia comes from. They are much weaker. The bone marrow can’t keep up with production. Spleen helps to recycle old RBC and it gets overworked. Blood flow can get blocked to spleen because of sticking together of RBC. Spleen also helps fight infection and if spleen is not working, then these patients will be at risk of infection as well
___________is the most common and severe form of sickle cell disease.
Sickle Cell anemia
How do people get sickle cell anemia?
They’re born with it! The person inherited two hemoglobin S genes from EACH parent. Therefore, it is an autosomal recessive disorder.
Again, this means in order for sickle cell disease to occur in a person they must have received TWO abnormal hemoglobin S genes for each of their parents (one from each). This disease is HOMOGYZOUS (Hemoglobin SS).
The parents normally don’t show signs and symptoms of the disease. They will each possess Hemoglobin A and S (one NORMAL hemoglobin and one ABNORMAL hemoglobin). This is known as SICKLE CELL TRAIT. It is rare for people who have sickle cell trait to show signs and symptoms of the disease because they usually have just enough normal hemoglobin to prevent sickling of the red blood cells. However, if two people with sickle cell trait have a child, there is a 25% chance the child will develop sickle cell disease.
caused by the inheritance of a gene for a structurally abnormal portion of the hemoglobin chain
Sickle Cell Anemia
Which population is most at risk for developing Sickle Cell disease?
Sickle cell anemia is most common in African-Americans.
WHY? According to the CDC.gov, it’s because 1 in 12 African-Americans in the US have the sickle cell trait, so it can easily be passed to their offspring. Other patient populations affected by this genetic disorder include: Middle Eastern, Asian, Caribbean, and Eastern Mediterranean.
In sickle cell anemia, hemoglobin _________ is partly or completely replaced by abnormal hemoglobin ________
A; S
it is caused by the inheritance of a gene for a structurally abnormal portion of the hemoglobin chain
Sickle Cell anemia tends to be diagnosed in the _________
very young pediatric populations like at 6-8 months of age
Many times (usually around 6 to 7 months) a parent will notice that their baby is all of the sudden extremely fussy (like the child is in constant pain), feverish, and has unusual swelling in the hands and feet (dactylitis…hand-foot syndrome). These signs and symptoms present because the baby’s RBCs have started to sickle and cause extreme pain. The sickling decreases blood flow to the extremities (hence hands and feet) and organs.
WHY do S/S of sickle cell anemia appear around 6-8 months perhaps and not at birth or around 2 to 3 months?
Because in utero and during the first 6 months of age, the baby has fetal hemoglobin (remember this because we talk about this type of hemoglobin for the treatment of this condition with the medication Hydroxyurea) in their system that is the main carrier of oxygen. However, around the age of 6 months this type of hemoglobin diminishes and the type of hemoglobin their genetic code gave them takes over…..which is unfortunately hemoglobin SS.
Sickle cell anemia testing is part of newborn screening in most hospitals. Tests used include:
Dithionite (Sickledex): a blood test that assesses for abnormal hemoglobin S…it doesn’t differentiate between if the person has sickle cell trait or sickle cell disease.
Therefore, a hemoglobin electrophoresis will need to be performed. This is a blood test that assesses for various types of hemoglobin.
a normal red blood cell is
round, smooth and concave with flat centers on both sides
no nucleus present
Benefits: easily squeeze through our vessels, carry O2
hemoglobin can really only carry oxygen well if there is the ________________ type of hemoglobin, A
normal
Hemoglobin S causes the RBCs to be………
When does this happen ? What does it lead to ?
causes RBC to be stiff, sticky and to form sickle shape. these can easily stick together. Not vessel friendly. Can cause circulation problems
sickling happens especially when there is a low amount of oxygen in the body causing the patient to experience a sickling episode (sickle cell crisis).
this is when signs and symptoms will manifest themselves in a sickle cell patient.
most patients with sickle cell anemia have anemia because
of the reduced life span of the weakened RBC
What’s one of the jobs of the RBC?
To carry oxygen…..and it does this with the help of HEMOGLOBIN! For a RBC to achieve this, it must have hemoglobin A present so the shape of the red blood cell won’t change.
It is important to remember that most patients with sickle cell anemia will usually just have __________ and they won’t have major signs and symptoms until a crisis episode.
anemia
When the RBCs__________, this abnormal shape causes the red blood cell to become stuck in vessels (blocking blood flow)…so organs and tissue suffer….which leads to many signs and symptoms, especially pain.
sickle
Red blood cells with hemoglobin S are very strong and never rupture. They live 120 days compared to the normal 20 days. The bone marrow cannot keep up with producing RBCs, so the patient is anemic. TRUE OR FALSE
FALSE
Red blood cells with hemoglobin S are very weak and easily rupture. They only live 20 days compared to the normal 120 days. The bone marrow cannot keep up with producing RBCs, so the patient is anemic.
Factors that can cause Sickle Cell Crisis: SICKLE
There are various types of sickle cell crisis, which occur when there is something causing the body to increase its demands for oxygen OR there is something affecting how oxygen is transported.
Significant blood loss…surgery, trauma etc.
Illness (at risk for this due to spleen function being affected)
Climbing or flying to high altitudes
Keeping continued stress (physical or mental)
Low fluid intake (dehydrated)
Elevated temperature…..fever, strenuous exercise (extreme temperature changes like cold weather or cold water….like swimming in cold can lead cells to sickle) these increase the body’s demand for oxygen, which stresses the hemoglobin S out and can cause sickling
What are the types of sickle cell crisis ?
VHAN
Vaso-occlusive
Hyperhemolytic:
Aplastic:
Non-functional spleen
fever, pain, edema in the hand and foot (seen in babies)….RBCs sticking together blocking blood flow which can lead to decreased circulation to organs, tissues along with infarction (stroke, renal issues).
What type of sickle cell crisis?
Vaso-Occlusive
destruction of RBCs at an accelerated rate….remember these RBCs are weak. When RBCs rupture they release bilirubin. Normally, the body (gallbladder and spleen) can keep up with the recycling of the RBCs and clean-up of bilirubin. However, this is not the case here in SCA…the patient can experience jaundice, gallstones, anemia etc
Hyperhemolytic
the halt of red blood cell production….bone marrow cannot keep up with producing red blood cells so the patient will cease in making RBCs….the patient will have anemia… Which type of sickle cell crisis ?
Aplastic
the spleen helps recycle old RBCs and filters the blood to kill foreign invaders. In SCA, the spleen can become congested with sickled RBCs, which leads it to swell and not work properly. The patient is at risk for infection and many patients will need their spleen removed.
Which type of crisis ?
Non-functional spleen
In sickle cell anemia, Crises vary among patients….some can have them randomly, while others have them frequently. TRUE OR FALSE
TRUE
S/S of Crisis in Sickle Cell Anemia
Dactylitis (early sign seen in babies at 6 months): hand-foot syndrome….blood flow being blocked to hands and feet…will be swollen and fever present
Pain (very severe)….back, joints, chest etc. comes in episodes
Anemic: RBC dying too soon: fussiness, tired, tachycardia, jaundice or pale (for dark skinned patients assess mucous membranes), delayed growth, shortness of breath
Infection risk: spleen recycles old RBCs and helps us fight infection by filtering out foreign invaders….sickled RBCs become trapped in spleen and this leads it to swell and not work properly…..at risk for infection, especially pneumonia (needs pneumococcal vaccine and flu, meningococcal)….some patients need a splenectomy
Gallstones: WHY? sickled RBCs are constantly breaking down and releasing bilirubin, which leads to gallstones because there is too much bilirubin for the gallbladder to manage
Stroke: if sickled RBCs stick together and block blood flow to the brain…blood supply is limited to the brain leading to a decrease in brain blood supply….can cause mental and physical disabilities….NEURO checks very important.
Eye problems: vision issues due to the blockage of blood flow to eye vessels from sickled cells (needs eyes checked regularly)
Risk for abnormal clotting due to an increase in blood coagulation: at risk for DVT or PE
Leg ulcers (older children and adults): lack of blood flow…painful and very slow healing
Acute chest syndrome (happens due to infection like pneumonia or embolism or sickled cells blocking perfusion to lung tissue): chest pain, cough, fever, low oxygen saturation, new chest x-ray infiltrate….very deadly…monitor respiratory status
Also, damage to the organs that depend on high blood flow: kidneys, liver, heart…blood flow limited
Why should cold compresses not be used in Sickle Cell Anemia crisis?
cold compresses can actually increase the demand for __________ and cause ___________
oxygen; sickling
Nursing Interventions for Sickle Cell Anemia
Sickling of RBCs occuring: focus hydration, oxygen, pain, at risk for infection, monitor respiratory status, neuro checks, at risk for acute chest syndrome, prevention of future crisis episodes, medications, blood transfusions
Pain: opioids around the clock (PRN not the best at this time until crisis over)
IV fluids and oral fluid: dilutes blood and helps kidney function (blood flow is being limited because RBCs are sticking together)
Oxygen: remember RBCs are stressed because of the lack of oxygen….this helps with alleviating the sickling
Penicillin: prevents infection or other antibiotics to treat (some MDs will order some patients to take prophylactic doses of PCN to prevent infection because their risk)…. if patient develops acute chest syndrome due to pneumonia may be ordered antibiotics.
Blood transfusion to replace RBCs and helps with anemia and increases oxygen levels in the body…….for multiple transfusions watch for iron overload
Bed rest
Educate about preventing infection (needs vaccines to be up-to-date, hand hygiene, avoid extreme weather and physical activities, mental/physical stress, staying hydrated, avoiding smoking, high altitudes)
Keep extremities elevated and extended to prevent swelling and helps blood flow
Remove restrictive clothing because it decreases perfusion
Warm compresses (not cold leads to sickling) for painful areas
Folic acid administration: helps make RBCs…..NOT iron….this doesn’t help with this type of anemia but can actually build up in the body causing toxicity and harm to organs
Medication for Sickle Cell anemia
Hydroxyurea: this helps actually treat cancer, but it will help with SCA in that it will help create fetal hemoglobin (hgb F). This helps decrease sickling episodes and this protein is present at first til 5-6 months of age, which is why babies don’t start showing signs and symptoms until after then. It will also help with anemia (decreasing the need for blood transfusions)….Side effect: lowers WBC count
Stem cell transplant: to cure….bone marrow will make healthy RBCs…needs a matched donor
Nursing Interventions to Prevent Sickle Cell Crisis
Avoid High altitudes get vaccines prevent infection hydration decrease stress levels no smoking don't overdo exercise
Hydroxyurea produces ____________ but it lowers the _____________ count
fetal hemoglobin; WBC
