Clinical Medicine Exam 4 Flashcards
(80 cards)
1
Q
What does oxygen saturation measure?
A
the % of hemoglobin that is saturated with oxygen
2
Q
What are the components of blood?
A
- plasma-proteins, water, other solutes
- buffy coat
- formed elements-platelets, leukocytes (neutrophils, lymphocytes, monocytes, eosinophils, basophils), erythrocytes
3
Q
What are the functions of erythrocytes?
A
- transport hemoglobin-O2 carrier
- transport CO2 in form of bicarbonate away from the tissues to the lungs
- act as an acid base buffer (binds H+)
4
Q
If you live at a higher altitude, will you have more or less RBCs?
A
More
5
Q
What is blood hematocrit and what is its normal value?
A
% of blood that is RBCs, 40-45% (females 37-47%, males 42-52%)
6
Q
What are the exercise precautions for hematocrit levels?
A
Light exercise: >25%
Resistive exercise: >30%
7
Q
What are the normal values for hemoglobin?
A
Women: 12-16 g/dL
Men: 14-18 g/dL
8
Q
What are the exercise precautions for hemoglobin?
A
Below 10 g/dL=decreased endurance, may be theshold for resistive exercise/ambulation
9
Q
What is the definition of orthostatic hypotension?
A
Drop of 20 mmHg systolic with a subsequent increase in pulse
10
Q
How many hemoglobin molecules are there per erythrocyte?
How much oxygen is each gram of hemoglobin able to bind with?
A
- Millions
2. 1.34 mL of O2
11
Q
Where are RBCs produced?
A
exclusively in bone marrow
12
Q
Which bones produce RBCs?
A
Until 5 years old=virtually all bones
After 20 years old=mostly flat, membranous bones (vertebrae, sternum, ribs, ilea), only proximal portions of humerus and tibia=but overall have a decrease in RBC production
13
Q
What is the original precursor of RBCs?
A
hemopoietic stem cells (live in the bone marrow)
14
Q
What stimulates the production of RBCs?
A
erythropoietin
15
Q
Why do you need an adequate number of RBCs? What happens if there are too many?
A
Adequate=provide sufficient oxygen transport from the lungs to the tissues
Too much=would thicken the blood and impede blood flow
16
Q
What is the result of decreased O2 transport to tissues?
A
Increased rate of RBC production
17
Q
What can cause a decrease in O2 transport to tissues?
A
Hemorrhage, destruction of major portions of bone marrow, high altitudes, disease of circulation that decreases blood flow through peripheral vessels or a failure of blood oxygen absorption in the lungs
18
Q
Where is erythropoietin formed?
A
90% in the kidneys, 10% in the liver
19
Q
What hormones can increase the production of EPO?
A
Norepinephrine, epinephrine, prostaglandins
20
Q
Why do patients with End Stage Renal disease have decreased RBCs?
A
They only have 10% of the normal erythropoietin
21
Q
What purposes do the leukocytes generally fill?
A
- The immune response- innate (granulocytes and monocytes) and acquired (lymphocytes)
- Inflammation
- Allergic reactions
22
Q
What are thrombocytes?
A
platelets
23
Q
What is a left shift?
A
An increase in the production/release of immature neutrophils, seen in a severe/acute bacterial infection
24
Q
What are the functions of neutrophils?
A
phagocytic, first on the scene in injury/infection, are short-lived and self-destruct after they ingest a pathogen
25
What cells make up the lymphocytes?
B cells, T cells, NK cells
26
What are the functions of monocytes?
Convert to macrophages-phagocytic activity
| Secretion of cytokines-stimulates the attraction of other phagocytes
27
What are the functions of the eosinophils?
Release of cytokines, growth factors, other enzymes/factors
| Important in parasitic infections and allergic responses
28
What are the functions of basophils?
Secrete: heparin, histamine, serotonin, kinins, leukotrienes, prostaglandins, platelet activating factor
Potentiates other vasoactive substances and inflammatory mediators
Assists in regulation of blood clotting
29
What are the normal values for WBCs? What are the critical values?
5000-10,000
Exercise may be contraindicated if less than 5000 and a fever greater than 100 degrees
Less than 1000 neutrophils=neutropenic precautions
30
What are the normal values for platelets? What are the critical values?
150,000-400,000
No resistive exercise under 50,000; serious danger if less than 20,000
31
What is the function of plasma?
carries antibodies and nutrients to tissues, removes wastes
32
What is the function of platelets and coagulation factors (from plasma)?
Control clotting
33
What is a severe complication of anemia?
Neurological deficits (because you do not have enough oxygen)
34
What are s/s of hematologic disease?
1. Exaggerated response to minimal exercise (dyspnea, chest pain, palpitations, severe weakness, fatigue)
2. Neurological symptoms (headache, drowsiness, dizziness, syncope, polyneuropathy)
3. Skin and fingernail bed changes (cyanosis, clubbing)
4. Easy bruising
5. Swelling, pain in joints
35
What hematologic disorder can light, lemon yellow tinted skin reveal?
Untreated pernicious anemia
36
What hematologic disorder can white, waxy appearing skin reveal?
severe anemia resulting from acute hemorrhage
37
What hematologic disorder can gray or green yellow skin reveal?
chronic blood loss
38
What hematologic disorder can gray tinted skin reveal?
leukemia
39
What hematologic disorder can pale hands or palmar creases reveal?
Anemia
40
What nail bed changes can occur with long standing iron deficiency anemia?
brittle and concave nails
41
What can pale or yellow oral mucosa or conjunctiva indicate?
Anemia
42
What is anemia and what is it usually seen in?
Too few erythrocytes
1. Iron deficiency, chronic GI blood loss due to NSAIDs
2. Chronic diseases (cancer, liver, kidney) or inflammatory (SLE or RA)
3. Neurologic diseases (pernicious anemia)
4. Infectious diseases (TB, AIDS) or neoplastic diseases
43
What are the s/s of anemia?
1. skin pallor (palms, nail beds) or yellow-tinged skin (mucosa, conjunctiva)
2. fatigue and listlessness
3. Dyspnea on exertion accompanied by heart palpitations and rapid pulse (more severe anemia)
4. Chest pain with minimal exertion
5. Decreased diastolic blood pressure
6. CNS manifestations (headache, drowsiness, dizziness, syncope, slow though processes, apathy, depression, polyneuropathy)
44
What occurs with blood loss anemia/hemorrhage?
Body replaces the fluid portion of plasma in 1 to 3 days, but leaves a low concentration of RBCs
RBCs usually return to normal in 3 to 6 weeks
45
What is aplastic anemia and what can cause it?
Bone marrow aplasia=due to lack of functioning of bone marrow, not enough RBCS produced
Caused by: gamma radiation (destroys bone marrow), cancer chemotherapy, excessive x ray treatment, industrial chemicals, drug sensitivities
46
What is megaloblastic anemia?
can be caused by atrophy of stomach mucosa, loss of entire stomach after surgical total gastrectomy, and intestinal sprue=a syndrome in which intestinal villi atrophy, stomach stapling=because you lose the section that releases a cofactor
RBCs are oversized, have bizarre shapes, have fragile membranes
rupture easily
47
When do you usually see sx of alchohol withdrawal?
36 hours
48
What 3 vitamins/minerals are important in blood?
vitamin B6, vitamin B12, folate
49
What is jaundice?
Inability of the liver to metabolize RBCs, causing a build up of bilirubin
50
What can different nails indicate?
Pale nails=CHF, anemia, liver diseases, nutritious diseases
White nails=liver problems such as hepatitis and jaundice
Yellow nails=fungal infection, more serious severe thyroid disease, lung disease, diabetes, psoriasis
Blue nails=lack of oxygenation (heart/lung probs)
Rippled nails=arthritis/inflammatory condition
Cracked/split nails=thyroid condition
Puffy nail fold=lupus, isolated infection
Dark lines=melanoma
Gnawed nails=may indicate anxiety
51
What is polycythlemia?
Too many RBCs, also called erythrocytosis
52
What are the two types of polycythemia?
Primary polycythemia=rare bone marrow neoplasm
Secondary polycythemia=decreased O2=may be due to living at high altitudes, smoking, radiation, chronic heart/lung disorders
53
What are the clinical s/s of polycythemia
```
General malaise and fatigue
Shortness of breath
Intolerable pruritis
HA
Dizziness
Irritability
Blurred vision
Fainting
Decreased mental acuity
Feeling of fullness in the head
Disturbances of sensation in the hands and feet
Weight loss
Easy bruising
Cyanosis
Clubbing of the fingers
Splenomegaly
Gout
Hypertension
```
54
How does polycythemia affect the blood?
Increases viscosity, which can lead to increased BP and hematocrit levels
55
What is polycythemia vera?
Caused by a lack of proper feedback control=decreased RBC production but increased RBCs
Usually causes excess of WBCs and platelets as well
Viscous blood plugs capillaries
56
What is sickle cell/hemolytic anemia?
RBCs contain abnormal hemoglobin S1 containing faulty beta chains=when exposed to low concentrations of O2,, RBC develops a sick appearance rather than a biconcave appearance
RBCs are very fragile, lead to serious anemia, also clump/agglutinate and don't make it through the capillaries
57
How does one contract sickle cell anemia?
It is an inherited autosomal recessive disease, meaning both copies of the gene in each cell have the mutation
58
What are the clinical s/s of sickle cell anemia?
```
Pain (in abdomen, chest, headache)
Bone/joint episodes from ischemic tissues (low grade fever, extremity pain, back pain, periosteal pain, joint pain-shoulder/hip)
Vascular complications (CVA, chronic leg ulcers, AVN of femoral head, bone infarcts)
Pulmonary episodes (chest pain, dyspnea, tachypnea)
Neurologic manifestations (seizures, dizziness, drowsiness, stiff neck, paresthesias, cranial nerve palsies, blindness, nystagmus, coma)
Hand foot syndrome (fever, pain, dactylitis)
Splenic sequestration episode (liver/spleen enlargement/tenderness due to trapped erythrocytes, subsequent spleen atrophy due to repeated blood vessel occlusion)
Renal complications (enuresis/bed wetting, nocturia, hematuria, pyelonephritis, renal papillary necrosis, end stage renal failure)
```
59
What is the purpose of leukocytes?
They are the body's reaction to disease and foreign invaders.
60
What is leukocytosis?
An increase in the number of leukocytes, specifically neutrophils
61
What are the s/s of leukocytosis?
Fever
Sx of localized or systemic infection
Sx of inflammation or trauma to tissue
62
What is leukopenia?
Too few leukocytes
63
What are the s/s of leukopenia?
```
Sore throat
Cough
High fever/chills
Ulcerations
Persistent infections
Frequent/painful urination
```
64
What is Nadir?
The lowest point the WBC count reaches, usually occurs 7 to 14 days after chemotherapy or radiation therapy
65
What is thrombocytosis and what can cause it?
Increased platelet count, usually compensatory after surgery, hemorrhage, or splenectomy
66
What can affect platelets?
NSAIDS and anticoagulants affect platelet levels
Diet=lecithin prevents coagulation, vitamin K promotes it
Exercise helps destroys clots
Liver disease, radiation, chemotherapy
67
What are the clinical s/s of thrombocytosis?
Thrombosis, splenomegaly, easy bruising
68
What is thrombocytopenia?
Decreased platelet count
69
What are causes of thrombocytopenia?
```
Bone marrow failure
Radiation
Aplastic anemia
Leukemia
Metastatic carcinoma
Cytotoxic agents (chemotherapy)
Medications (NSAIDs, methotrexate, gold, coumadin/warfarin)
```
70
What are the clinical s/s of thrombocytopenia?
```
Bleeding after minor trauma
Spontaneous bleeding (petechiae=small red dots, ecchymoses=bruises, purpura spots=bleeding under the skin, expistaxis=nosebleed)
Menorrhagia (excessive menstruation)
Gingival bleeding
Melena (black, tarry stools)
```
71
T/F Patients with thrombocytopenia can demonstrate clumping and agglutination of platelets.
True
72
What is hemophilia?
bleeding disorder caused by a deficiency in 1 of 2 clotting factors: factor VIII or IX
Can be caused several different gene abnormalities
Pt bleeds unexpectedly or after minor injuries
73
How can you treat hemophilia?
transfusions are given to replace the missing clotting factors (can be prophylactic or incident related)
74
What are the 2 types of hemophilia?
Hemophilia A: 80% of cases, deficiency in clotting factor VIII
Hemophilia B: deficiency in clotting factor IX
**Bleeding patterns and consequences are similar
75
What are the clinical s/s of acute hemarthrosis associated with hemophilia?
```
Aura, tingling, or prickling sensation
Stiffening into the position of comfort
Decreased ROM
Pain
Swelling
Tenderness
Heat
```
76
What are the clinical s/s of muscle hemorrhage associated with hemophilia?
Gradually intensifying pain
Protective spasm of the muscle
Limitation of movement at the surrounding joints
Muscle assumes the position of comfort (usually shortened)
Loss of sensation
77
What are the clinical s/s of CNS involvement associated with hemophilia?
```
Intraspinal hemorrhage (rare)
Intracranial hemorrhage-irritability, lethargy, seizures, feeding difficulties, unequal pupils, apnea, vomiting paralysis, tense, bulging fontanelles, death
```
78
What are the clinical s/s of GI involvement associated with hemophilia?
Abdominal pain and distention
Melena (blood in stool)
Hematemesis (vomiting blood)
Fever
Low abdominal/groin pain due to bleeding into wall of large intestine or iliopsoas muscle
Flexion contracture of the hip due to spasm of the iliopsoas muscle secondary to retroperitoneal hemorrhage
79
How do you differentiate an iliopsoas bleed versus a hip bleed?
1. Trunk flexion=severe pain if iliopsoas bleed, mild if hip hemorrhage
2. Hip rotation=severe pain with hip hemorrhage, absent or mild pain with iliopsoas bleeding
80
What are long term consequences of hemophilia?
Repeated bleeds can cause fibrotic tissue and contractures
Possibility of peripheral nerve lesions from compression
Pseudotumor or bone erosion from hemarthrosis (can lead to an early joint replacement)
