1.3: Sources and Control of Preanalytical Variation
- Page ID
- 113850
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Use the following key to answer questions 1 through 4.
- 1,2, and 3 are correct
- 1 and 3 are correct
- 2 and 4 are correct
- only 4 is correct
- all are correct
- Moderate levels of hemoglobin can cause methodological interference in which of the following analytical procedures?
- cholesterol
- albumin
- triglycerides
- iron
- The information on a chain of custody document includes:
- subject name
- person sending specimen
- person receiving specimen
- condition of seals
- The purpose of a chain of custody document is to:
- ensure that no tampering of the sample occurred
- ensure that the specimen is derived from the appropriate individual
- ensure that the reported results are correct for
the appropriate individual - ensure that quality control was performed
- Which of the following patient variables can affect measured analyte concentrations?
- diurnal variation
- posture
- stasis
- height
- All of the following are higher in the morning than the afternoon or evening (in persons with a normal wake:sleep cycle) EXCEPT:
- ACTH
- Cortisol
- Iron
- Prolactin
- Renin/aldosterone
- Which of the following is typically decreased after meals?
- Chloride
- Gastrin
- Growth hormone
- Insulin
- Triglycerides
- EDTA contamination will decrease all of the following analytes EXCEPT:
- Alkaline phosphatase
- Calcium (spectrophotometric methods)
- Creatine kinase
- Magnesium (spectrophotometric methods)
- Potassium
- The mechanism of interference in hemolyzed samples is correctly matched with the test name in all of the following combinations EXCEPT:
- Bilirubin – release from red blood cells
- Cholesterol – interference in assay
- Creatine kinase – interference in assay
- Lactate dehydrogenase – release from red blood cells
- Magnesium – release from red blood cells.
- Appropriate tests to use for delta checks, since they show low intra-individual variation, little day to day variation, but higher inter-individual variation, include:
- Alkaline phosphatase
- Creatine kinase
- Glucose
- Lactate dehydrogenase
- Phosphate
- The percent intraindividual variation is highest for:
- Albumin
- Calcium
- Creatinine
- Sodium
- Triglycerides
- Regular aerobic exercise is associated with:
- Decreased glucose
- Decreased bilirubin
- Decreased creatine kinase
- Increased aspartate aminotransferase
- Increased alanine aminotransferase
- Short term, intensive exercise, such as running a marathon, is associated with:
- Decreased potassium
- Decreased uric acid
- Decreased glucose
- Decreased creatine kinase
- Increased phosphate
- All of the following increase after a meal EXCEPT:
- Glucose
- Insulin
- Iron
- Potassium
- Triglycerides
- Stress is associated with which of the following?
- Decreased cortisol
- Decreased catecholamines
- Decreased cholesterol
- Increased high density lipoprotein cholesterol
- Increased TSH
- All of the following are increased by upright posture EXCEPT:
- Albumin
- Calcium (total)
- Cholesterol
- Iron
- Potassium
- Which of the following statements regarding differences between arterial and venous blood is INCORRECT?
- Arterial blood has higher concentrations of metabolites extracted by tissue, such as oxygen and glucose.
- Arterial blood has lower concentrations of waste products, such as carbon dioxide and ammonia.
- Capillary blood is more similar to arterial than to venous blood.
- The difference between arterial and venous blood is increased with poor tissue perfusion.
- The difference between arterial and venous blood glucose is similar in fasting and postprandial collections.
- Answer
-
- b (p. 73)
- e (p. 73-74)
- a (p. 74)
- a (p. 66-68)
- d (p. 69)
- a (p. 69)
- e (p. 71)
- a (p. 73)
- a (p. 80)
- e (p. 67)
- c (p. 67-68)
- c (p. 67)
- d (p. 69)
- c (p. 68)
- d (p. 68)
- a (p. 70)