Ch. 21: Hematologic Disorders-Sickle Cell Anemia & Hemophilia Flashcards
Sickle cell disease (SCD) is a group of diseases in which abnormal sickle _____ replaces normal adult hemoglobin (Hgb A)
Hemoglobin S (HbS)
What is the most common form of SCD?
Sickle cell anemia is the homozygous and most common form of SCD
Manifestations and complications of SCA are the result of _____, which leads to increased ______, obstruction of ____, and tissue ____.
Result of RBC sickling which lead to
- increased blood viscosity
- obstruction of blood flow
- tissue hypoxia
Why are manifestations of SCA not usually apparent until later in infnancy?
Due to the presence of fetal Hgb
What causes the pain from SCA?
Tissue hypoxia, which causes ischemia, which results in pain
What is sickle cell crisis?
The exacerbation of SCA
SCD is what kind of disorder?
An autosomal recessive genetic disorder
Who does SCA primarily affect? Can it affect others?
Primarily African American, other forms of SCD are individuals of Mediterranean, Indian, or Middle Eastern descent
T/F: Children with sickle cell trait do not manifest the disease.
True…but they can pass the trait to their offspring
What are S&S of SCA?
SOB Fatigue Pallor/pale mucous membranes Jaundice Hands and feet cool to touch Dizziness Headache
SCA: What is a vaso-occulsive crisis and how long does it last?
A painful episode and it lasts 4-6 days
SCA: What are the acute signs of vaso-occulsive crisis?
- Severe pain (bones, joints, abdomen)
- Swollen joints, hands, and feet
- Anorexia, Vomiting, fever
- Hematuria
- Obstructive jaundice
- Visual disturbances
SCA: What are the chronic signs of vaso-occulsive crisis?
- Increased resp. infections and osteomyelitis
- Retinal detachment and blindness
- Systolic murmur
- Renal failure and enuresis
- Liver cirrhosis; hepatomegaly
- Seizures
- Skeleteal deformities; shoulder or hip avascular necrosis
SCA: What is sequestration?
Excessive pooling of blood primarily in the spleen (splenomegaly) and sometimes in the liver (hepatomegaly)
SCA: Sequestration–reducing circulating blood volume results in ____ and can progress to ___
Hypovolemia..progress to shock
SCA: Sequestration–What are the signs of hypovolemic shock?
Irritability Tachycardia Pallor Decreased urinary output Tachypnea Cool extremities Thready pulse Hypotension
SCA: Aplastic crisis..What is it and what is it usually triggered by?
Extreme anemia as a result of decreased RBC production
Triggered by infection
SCA: What is hyper hemolytic crisis?
Increased rate of RBC destruction leading to anemia, jaundice, and/or reticulocytosis
Is screening for SCA a mandatory thing for newborns?
Yes, in most states
What lab test detects anemia?
CBC
What lab test is a screening tool that detects the presence of HbS. What does this test NOT do?
Detects the presence of HbS= Sickledex (sickle-turbidity)…This test DOES NOT differentiate the trait from the disease!
What is the definitive diagnosis of sickle cell anemia? What does this test do?
Hemoglobin electrophoresis–separates the various forms of Hgb
What happens in lab findings during a sickle cell crisis?
- Hgb= decreased
- WBC, biliruben, reticulocyte levels= elevated
- Peripheral blood smear reveals sickled cells
What is the transcranial dropper (TCD) test and how often is this done?
Assesses intracranial vascular flow and detects the risk for CVA–done annually on children ages 2-16 who have SCD
SCA: Should we promote rest or exercise?
Rest–to decrease oxygen consumption
