Ch.46 Common Laboratory Tests Flashcards
1
Q
When do they usually collect specimens in general? NCLEX
A
Usually collected in early morning before intake of food and fluids; if done in fasting state, withhold
food and fluids for 8–12 hours prior to test.
2
Q
What kind of precautions should be used when collecting a specimen?
A
Collect using standard precautions to protect against exposure to blood or other body fluids; use strict
aseptic technique to protect client from infection.
3
Q
How should a lab specimen be labeled?
A
. Label specimens with client name, date, exact time of collection, and type of specimen
4
Q
Why should you avoid shaking blood?
A
Avoid shaking blood specimens to avoid hemolysis and send promptly to lab.
5
Q
Do you put a 24 hour specimen cup on ice?
A
If indicated.
6
Q
For a 24 hour urine wat should be done with the first urine?
A
At beginning of collection period, have client void and discard this urine; save all urine for next 24 hours
7
Q
What precautions do you wear for a 24 hour urine collection?
A
Transfer voided specimen into collection device using standard precautions.
8
Q
What does a ABG tell us?
A
A. Consist of serum (blood) pH, partial pressure of arterial oxygen (PaO2), partial pressure of carbon dioxide
(PaCO2), bicarbonate (HCO3¯), and base excess
9
Q
What is the normal pH range?
A
7.35-7.45
10
Q
What is the normal ABG for oxegen?
A
80–100 mmHg
11
Q
What is the normal ABG Carbon dioxide?
A
35–45 mmHg
12
Q
What is the normal Bicarb values?
A
22–26 mEq/L
13
Q
What is the normal sodium?
A
135–145 mEq/L
14
Q
What is the normal Potassium?
A
3.5 to 5
15
Q
What is the normal Chloride?
A
95–105 mEq/
16
Q
What is the normal venous bicarbonate?
A
23–29 mEq/L
17
Q
What is the normal calcium?
A
8.5–10.5 mg/dL or 4.5–5.5 mEq/L
18
Q
What is the normal magnesium?
A
1.6–2.5 mg/dL or 1.5-2.5 mEq/L
19
Q
What is the normal phosphate?
A
3–4.5 mg/dL
20
Q
What is glucose?
A
Glucose is an end product of carbohydrate digestion, glycogenolysis, and gluconeogenesis.
21
Q
What is the job of glucose?
A
Primary fuel source for cellular energy, especially for brain and red blood cell function.
22
Q
What do we use glucose studies to diagnoses?
A
Used to diagnose diabetes mellitus and hypoglycemia.
23
Q
How long must a patient fast for a glucose study?
A
Client must fast for 8–12 hours prior to drawing lab sample, with no ingestion of foods, beverages, or
medications (oral antidiabetics or insulin).
24
Q
What is the normal fasting glucose?
A
70–110 mg/dL
25
What is the normal random glucose fingerstick?
60–110 mg/dL
26
What is the normal two hour postprandial blood glucose?
less than 140 mg/dL
27
Why do we do a Glucose Tolerance Test?
Used as a screening test for clients at risk of DM and as diagnostic aid.
28
How should glucose levels rise and fall?
predictable amounts following ingestion of a specific glucose load
29
How can you tell if they have Diabetese Mellitus with a Glucose tolerance test?
with DM, glucose levels peak at higher levels and fall more slowly than normal
30
How should the client eat before a glucose tolerance test?
What should you not eat or drink before test?
. Eat high-carbohydrate (CHO) diet (200–300 grams daily) for 3 days prior to test (give client list of
high-CHO foods as needed).
Do not drink alcohol or coffee or smoke for 36 hours before test (eliminates alcohol, caffeine, and
nicotine as interfering factors with test results)
31
How long do you have to fast before a glucose tolerance test?
Fast for 10–16 hours before test as instructed by healthcare provider.
32
What should not be taken before a glucose tolerance test?
What else should dth client not do before the test?
Do not take any oral antidiabetic medications or insulin prior to test
Do not exercise vigorously for 8 hours before or after test; sit quietly during test
33
What is a normal A1C?
3.5–6%
34
What is considered a good A1C?
7% or lower
35
What is considered a poor A1C?
8% or higher.
36
What does Prothrombin and international ratio INR measure?
Measures time needed for prothrombin (a vitamin K–dependent glycoprotein produced in liver) to
form a fibrin clot via extrinsic clotting pathway.
37
What do we usually use PT and INR to assess?
NCLEX
. Commonly used to assess effectiveness of oral anticoagulant warfarin or to diagnose disseminated
intravascular coagulopathy (DIC), vitamin K deficiency, or liver dysfunction.
38
What is the normal PT?
. Normal reference ranges for PT may vary slightly by lab but are generally 11–13 seconds. (Plus or minus 2).
39
What is the normal refernace for warfarin?
therapeutic range for warfarin is
1.5–2 times the control value
40
What makes INR diffrent from PT?
INR is similar to PT but standardizes normal values across all lab systems.
41
What is the therapeutic range for warfarin?
Therapeutic range for
warfarin is 2.0–3.0 for standard therapy and 3.0–4.5 for high-dose therapy.
42
What is the normal baseline ranges for INR?
baseline normal reference
range is 0.8–1.2 (U.S. and Canada).
43
How should you go about drawing a PT?
Draw baseline PT before beginning oral anticoagulation and repeat at specified intervals to monitor
progress of therapy; apply pressure to venipuncture site for 3–5 mins.
44
What does it mean if PT and INR IS LOW?
Low values indicate ineffective therapy and
high values indicate risk for bleeding or hemorrhage.
45
What do we need to teach the clients about green leafy vegtables?
. Teach client to maintain steady but moderate intake of green leafy vegetables (they are rich in vitamin
K and will decrease PT/INR).
46
What is aPTT?
Activated partial thromboplastin time.
47
What does aPTT measure?
Measures time needed for recalcified, citrated plasma to clot after adding activated thromboplastin
reagent; reflects intrinsic clotting pathway.
48
What is the main thing we measure with aPTT?
Commonly used to assess heparin therapy.
49
What two diseses can elevated aPTT indicate?
Elevated in liver disease and DIC.
50
What is the normal aPTT?
NCLEX
Normal reference range is 20–35 seconds.
51
What is the normal therpetic range for heparin?
NCLEX
therapeutic range for heparin
therapy is 1.5–2.5 times the control in seconds (often 60–80 secs).
52
What should be done before starting heparin?
Emergency Room
Draw baseline aPTT before beginning heparin therapy and repeat at specified intervals to monitor
progress of therapy.
53
Where can you not draw lab values from with heparin?
NCLEX
Never draw from the bein in same arm that heparin is infsing.
54
What do low levels indicate for heaprin?
Low values indicate ineffective therapy.
55
What do high aPTT numbers mean with heparin?
High values indicate risk for bleeding or hemorrhage.
56
What does bleeding time tell us?
Evaluates overall functioning of platelets in achieving hemostasis.
57
What is the normal bleeding times?
Normal adult reference range is 1–3 minutes (Duke method), 3–6 minutes (Ivy method), 180–570
seconds (Canada)
58
How do you conduct a bleeding test?
Skin puncture is done to determine time needed for bleeding to stop.
59
Before a bleeding test what should not be given?
Ensure that client has not received drugs that interfere with test (aspirin, aspirin-containing products,
anticoagulants) for 3 days prior to test, and apply pressure dressing after procedure if needed.
60
What does a D-dimer tell us?
That there is a blood,clot somewhere in the body.
61
What is the normal D-dimer?
Normal value is 0.5 mcg/mL FEU (fibrinogen equivalent units) or 0–3 nmol/L.
62
What are the main conditions that causes an elevated D-dimer?
Results are prolonged in
conditions such as DIC, deep vein thrombosis, pulmonary embolism, and other arterial or venous thromboses.
63
What are the coagulation studies?
PT
INR
D-DIMER
aPTT
Bleeding time
64
What labs are on the coagulation studies?
Hematocrit
Hemoglobin
Red blood Cell count,
Plalet count
White blood cell count
65
What is hematocrit?
Is the proportion of RBCs to plasma (liquid portion of blood), reported as a percentage.
66
What is a buffy coat?
Hematocrit can be falsely elevated when white blood cell (WBC) counts are markedly elevated (referred to as
“buffy coat”).
67
Waht can fasly lower hematocrit?
Can be falsely lowered with hemodilution (increased water component of blood)
68
What is the normal reference range for hematocrit?
Normal reference range is 40–50% for males and 38–47% for females.
69
What is hemoglobin?
Hemoglobin is a major component of erythrocytes that combines loosely with oxygen (O2) and carbon
dioxide (CO2) for transport in circulation
70
What are the main condictions that can cause a abnormal hemoglobin?
Abnormal hemoglobinopathies include sickle cell disease and thallasemias; decreased Hgb commonly
indicates anemia.
71
What i sthe normal Hemoglobin?
NCLEX
Normal reference range is 13.5–18 grams/dL for males and 12–16 grams/dL for females in U.S.
72
What is the relation between H&H?
Normally, Hgb and Hct levels parallel each other; Hct is usually three times higher than Hgb level.
73
What is another name for red blood cells?
Erththrocyte.
74
Where are red blood cells formed?
RBCs are formed in bone marrow and removed by liver, spleen, and bone marrow.
75
How long do RBC's live?
Lifespan of RBC is approximately 120 days.
76
What is the main job of red blood cells?
Carry hemoglobin molecules responsible for O2 transport to tissues.
77
What is the main thing a low hemoglobin indicate?
Anemia.
78
What is the normal red blood cell range?
Normal reference range: 4.0–5.5 million cells/microliter for adult females and 4.5–6.2 million cells/
microliter for adult males in U.S.
79
How do we further evaluate anemia?
NCLEX
Abnormal values indicate anemia or blood dyscrasias; further evaluation of anemia can be done by
evaluating RBC indices (mean corpuscular volume [MCV], mean corpuscular hemoglobin [MCH], and
mean corpuscular hemoglobin concentration [MCHC]).
80
What is the normal range for platlets?
Normal reference range: 150,000–450,000 per cubic mm (mm3
) in U.S.
81
Where are platlets made?
Bone marrow.
82
How long do platelets live?
A lifespan of about 10 days.
83
Wat happens when you get a cut,m what do platlets do?
When microtrauma occurs and damages blood vessels, platelets aggregate to form hemostatic plug to
initiate clot formation.
84
What is somthing that can stop pleatlets?
Platelet aggregation is inhibited by drugs such as aspirin.
85
What is thrombocytopenia?
Decreased platelet levels.
86
What are some diseases that cause thrombocytopenia?
cancer chemotherapy from bone marrow
suppression, idiopathic thrombocytopenic purpura (ITP), most leukemias, uremia, and some infections
such as infectious mononucleosis.
87
What does decreased platlets put you at risk for?
NCLEX
An insufficient number of platelets leads to increased risk of bleeding; bleeding precautions should be
instituted if platelet count drops below 50,000 cells/mm3
or 50 * 109
/L
88
What is the normal White blood cell count?
NCLEX
Normal total WBC reference range: 5000–10,000 cells/mm3
(U.S.).
89
What are neutrophils?
Neutrophils defend against inflammation, tissue injury, and infection.
90
What does a shift to the left mean?
NCLEX
A “shift to the left” indicates a greater number of neutrophils are immature (bands) because of need
for more rapid production to combat inflammation or infection.
91
What does a shift the the right mean?
A “shift to the right” indicates cells with excessive nuclear segments, seen with liver disease, megaloblastic and pernicious anemias, and Down syndrome.
92
What do eosinophils do?
Eosinophils increase during allergic and parasitic conditions and decrease with higher levels of steroids.
93
When do basophils increase?
Basophils increase during healing process and decrease when steroid levels rise.
94
What is the job of monocytes?
6. Monocytes (“monos”) are second line of defense against bacterial infection and foreign substances;
these macrophages ingest larger particles and debris from cellular destruction; may also kill tumor
cells—mechanism unclear
95
What do lymphocytes do?
Lymphocytes (“lymphs”) elevate during chronic and viral infections and lymphocytic leukemia; consist
of B lymphocytes and T lymphocytes.
96
What is the normal range for neutrophils?
50–70% or 2500–7000 cells/microliter
97
What are the three cardiac function test?
Serum Lipids
Creatine Kinase (CK) OR Cpk
Troponins
98
What are the two main lipids?
Primary measurements include total cholesterol, low-density lipoproteins (LDLs), high-density
lipoproteins (HDLs), and triglycerides.
99
What does increased serum lipids lead to?
NCLEX
Increase risk of heart disease, stroke, and peripheral vascular
disease.
100
What is special about HDL?
High HDL levels seem to be cardioprotective.
101
What do elevated triglycerides indicate?
Hyperlipidemia
(possibly familial)
102
What should you teach the client before having serum lipids drawn?
NCLEX
Teach client to avoid alcohol intake for 24 hours before test and avoid high-cholesterol foods the
evening before blood is drawn.
103
Can they eat before serum lipid panel?
Client must fast (except water) for 12–14 hours prior to test.
104
What is the normal total cholesterol?
less than 200.
105
What is the normal LDL?
Less than 130.
106
What is the desired HDL?
60 OR ABOVE.
107
What are the normal triglycerides?
less than 200
108
What is Creatine kinase and creatinine phosphokinase?
An enzyme found in large amounts in cardiac and skeletal muscle and in low amounts in brain tissue;
enzyme is released from cells upon cell death
