module 5 Heme Flashcards
1
Q
- Blood is comprised of …% plasma, and …% formed elements.
- Plasma contains …% water, …… % proteins, and …. % other solutes.
- Formed elements is made of 99% of what? <1% of what, and <1% of what?
A
- 55% plasma, 45% formed elements
- 91% water, 7% proteins, and 2% other solutes like gas etc.
- erythrocytes, platelets, and leukocytes
2
Q
- Erythropoesis is under …….. control. Which hormone triggers it?
- What produces erythropoetin, and what is its target?
- Name a few possible triggers for erythropoetin release.
- What 2 organs are responsible for breaking down blood cells?
A
- hormonal, erythropoetin
- kidneys. Target is bone marrow
- decreased rbc’s, blood flow, hemoglobin synth, hemorrhage, increase O2 consumption
- spleen and liver
3
Q
- What is O2 bound to in rbc’s?
- What is hemoglobin composed of? How many O2 per hemeglobin molecule?
- Rbc’s last for about ……. days then they start to get stuck in the …………., and break down into what?
- What happens to heme of broken down rbc? Which protein carries Fe to the liver and bone marrow? What protein binds unconjugated bilirubin?
- What happens to globin when rbcs break down?
- What is responsible for engulfing the old rbc and breaking it down?
A
- the heme groups of hemoglobin.
- 4 polypeptide chains (a1, a2, B1, B2). Each chain has a heme group. 4.
- 120 days, spleen, Heme and globin
- Heme breaks into Fe2+ (ferrous iron), which gets recycled and protopoferin 9 which becomes unconjugated bilirubin. Transferin transports Fe. Albumin transports protoporferin 9.
- breaks into the 4 polypeptide chains and gets recycled by the body.
- macrophage
4
Q
- unconjugated bilirubin in the blood is ………… ………… ………… . What is it bound to?
- When does bilirubin become conjugated? Is it water soluble? What does it become next, and where does it go?
A
- not water soluble. albumin
2. in the liver with glucuronic acid. Yes. Bile. Goes to colon (makes brown poo), and kidney (makes yellow pee)
5
Q
- The coagulation pathway is only effective in ……………………..? What are the 3 steps?
- What does vasospasm achieve?
- What important factor is part of platelet plug formation, and what does it do?
- What happens in fibrin clot?
- What kind of deficiencies happen in clotting?
- What over-the-counter medication inhibits TXA2?
A
- Small caliber vessels. Vasospasm, platelet plug formation, fibrin clot
- decreases blood loss by slowing the flow. Greater contact time for blood to clot around wound.
- Von Willebrand factor (vwf) triggers platelet release of thromboxane a2 (TXA2), make platelets stick together forming plug.
- pulls wound edges together and stabilize platelet plug.
- lack vwf, lack of TXA2, or factor 8.
- Aspirin (anticoagulant)
6
Q
- What is fribinolysis?
- What are the enzymes that cause clot break down.
- In the body’s tug-o-war between clotting and fibrinolysis, which process is generally favored?
A
- the process of breaking down fibrin clots
- tissue platinogen activator (t-PA), or u-PA (both made by endothelial cells) converts plasminogen to plasmin (breaks down clots).
- fibrinolysis unless there is a tissue injury that needs clotting.
7
Q
- In its broadest sense, what is anemia?
- Anemia is defined by reduction in what substances? What do each of these cause?
- What is hematocrit?
- Is anemia a disease?
- What are the defining Hg or Hct levels in men and women?
A
- Functional inability of the blood to supply the tissues with adequate oxygen for proper metabolic function
- Hemoglobin (Hg) concentration, • Hematocrit (Hct) concentration,• Red blood cell (RBC) count. All cause decreased O2.
- the ratio of the volume of red blood cells to the total volume of blood
- Not a disease, rather an expression of an underlying disorder
- Men Hg = <13g/dL, Hct = <41%. Women Hg = <12g/dL, Hct = <36%
8
Q
- How do we classify anemia (4)?
- Anemia due to hemolysis or bleeding is characterized by …………. .
- What is MCV? MCHC?
- In what two ways can we approach anemia?
- What 3 things would the kinetic approach see in anemia?
- What 2 ways would the morphological approach see anemia?
A
- rbc size (microcytic), color (relates to Hg), shape, decreased production vs. increased rbc loss.
- reticulocytosis (new rbcs in the flow)
- Mean Corpuscular Volume, Mean Cell Hemoglobin Concentration
- kinetic classification, or morphological (appearance of cell)
- Decreased rbc production (nutrient lack, bone marrow disorder or suppression)
Increased rbc destruction (inherited or acquired hemolytic anemias like sickle cell or thalessemia)
Blood Loss from tumor, trauma, or chronic
- Cell size and cell color. Micro/macrocytic normochromic
9
Q
- What would cause microcytic rbcs, and what is the MCV size?
- What are the values for normocytic rbcs?
- What would cause macrocytic rbcs, and what is the MCV size?
A
- reduced iron, heme, or globin. MCV<80
2. 80
10
Q
- O2 deficit leads to
A
- Diminished cell metabolism and reproduction
- Tachycardia and peripheral vasoconstriction,
- Fatigue, pallor (pale face), dyspnea, tachycardia,
- Decreased regeneration of epithelial cells
- Digestive tract becomes inflamed and ulcerated, leading to stomatitis
- Inflamed and cracked lips
- Dysphasia
- Hair and skin may show degenerative changes.
11
Q
- Decreased O2 from anemia causes (5)
2. Decreased volume from anemia causes (4):
A
1. Exertional dyspnea • Dyspnea at rest • Fatigue • Bounding pulses • Lethargy, confusion
- • Fatigue
• Muscle cramps (can’t unclench)
• Postural dizziness and Syncope (fainting from lack of O2 to brain)
12
Q
- What is another name for macrocytic-normochromic anemia, and what is the common name for this?
- What causes the cells to be so big?
- What causes pernicious anemia?
- Name the 2 substances that act as coenzymes to DNA maturation:
A
- Megaloblastic anemia. Pernicious anemia or folate deficient
- defective DNA synthesis in rapidly dividing stem cells caused by lack of B12 or folate
- Autoimmune against parietal cells that make intrinsic factor required for B12 absorption. Results in deficient B12
- B12 and Folate
13
Q
- What are the symptoms of pernicious anemia (macrocytic normochromic)?
- What are the 3 diagnostic tests for pernicious anemia?
- What is the treatment for pernicious anemia?
A
1. Hg= 7-8g/dL. • Difficulty walking • Loss of appetite • Abdominal pain • Weight loss • Sore tongue • Neurologic manifestations
- Methylmalonic acid and homocysteine level (maturation of dna)
- Blood work test for antibodies against parietal cells
- Schilling test (academic and research). No longer done.
- lifelong high dose B12 replacement (parentarel. injection)
14
Q
- Is folate deficiency pernicious anemia?
- Where does folate absorption occur?
- What symptoms differ between folate def and pernicious? Where does folate deficient anemia present?
- What is treatment for folate deficient anemia
A
- No. Similar symptoms, but methylmalonic acid is normal in folate deficient anemia
- small intestine
- Folate deficient lacks neurological symptoms. Does get cheilosis (mouth fissures), and stomatitis (ulcerations). Normally presents on skin
- daily oral administration of folate
15
Q
- What type of anemia is Microcytic Hypochromic, and what disorders does it relate to?
- Is iron deficient anemia the most common type?
- Name some reasons that iron deficient anemia occurs:
A
- Iron deficient anemia. Disorders of iron metabolism, porphyrin, heme, and globin synthesis
- yes
- blood loss occult or overt, menstruation, pregnancy, rapid growth in children, inadequate iron in diet, too much cow’s milk in infancy