Flashcards in Screening 4 Deck (29)
Polycythemia occurs when there are too many
In polycythemia, increased concentration of hemoglobin leads to
- increased blood volume
- increased blood viscosity
Increased blood volume and viscosity limits blood's ability to
What are the two forms of polycythemia?
primary polycythemia aka
What is primary polycythemia?
rare bone marrow neoplasm
Primary polycythemia and RBC/WBC
- decreased RBC production
- increased # of RBCs
- usu causes excess WBC and platelet production
What happens to blood in the capillaries with polycythemia and what outward sign does this produce?
- viscous blood plugs capillaries
- get "hot bath sign"
Secondary polycythemia results from
decreased oxygen to the tissues
Secondary polycythemia may be due to (environmental)
- living at high altitudes
- chronic heart/lung disorders
Initial s/s of polycythemia
- usually vague
- watch for increased BP and hematocrit levels
Why are BP and hematocrit levels increased with polycythemia?
due to increased blood viscosity
What are the 2 features of sickle cell anemia?
- hemolytic anemia
What genetic mutation is seen in sickle cell anemia?
RBCs contain an abnormal hemoglobin S
What does abnormal hemoglobin S cause?
- aggregation into long beta chains
- alters shape of cell
When hemoglobin S is exposed to low concentrations of O2, what happens?
develops sickle appearance instead off a biconcave disc
In addition to the shape change seen with sickle cell anemia, what else happens to the RBC? What does this cause?
- RBCs are highly fragile
- leads to serious anemia
What type of disease is sickle cell anemia?
- autosomal recessive
sickle cell anemia: autosomal recessive means
both copies of the gene in each cell have mutations
Sickle cell anemia is the most common ________
inherited blood disorder in the US
sickle cell anemia: African Americans
1 in 500
sickle cell anemia: Hispanic Americans
1 in 1000
manifestation of sickle cell anemia is characterized by
- a series of "crises/episodes" of acute manifestations of the disease
- range in severity
sickle cell anemia: recurrent episodes result in
progressive damage to most organs
What medical issues are frequent and severe with pts who have sickle cell anemia?
- cognitive impairment
The hot bath sign causes:
Clinical signs of polycythemia are usually vague initially: what are some common things that happen?
- Decreased mental acuity
- Blurred vision