LABMAN SEMINAR 2 RECALL Flashcards
Physiologic factors with diurnal variation are encountered when testing for
- Hormones
- Iron
- Acid phosphatase
- Urinary excretion
- Electrolytes
Although diet contribute a significant change in the laboratory results, most of the instances it can transient and easily controlled. True or False?
True
How does Hyperventilation affect the body?
Hyperventilation, a condition caused by stress, can general affect the acid-base balance of the body
Effect of upright position in blood samples
Upright position increases hydrostatic pressure.
1. Decrease of plasma volume
2. Increase of protein concentrations
Effect of incorrect application of the tourniquet and fist exercise
- Lactate concentration (false increase)
- Serum enzymes
- Proteins
- Protein-bound substances
a. Cholesterol
b. Calcium
c. Triglycerides
Effect of bed rest to the level of hemoglobin
After bed rest in the hospital, hemoglobin levels may decrease to a point where false diagnosis may be deduced (hemolysis or internal hemorrhage)
Effect of IV administration to blood and analytes
Diluted or decrease in levels
Four (4) age groups:
a. Newborn
b. Childhood to puberty
c. Adult
d. Elderly
After puberty, men have generally higher concentration of the following analytes than women because of larger muscle mass.
AAAC
Alkaline phosphatase
Aminotransferase
Aldolase
Creatine kinase
Women have lower levels of the following analytes than men:
CASHFM
Calcium
Albumin
Serum iron
Hemoglobin
Ferritin
Magnesium
Effects of Tobacco Smoking
i. Increase levels of carboxyhemoglobin, plasma catecholamine
and serum cortisol.
ii. In response, there is a decrease in eosinophils and increase in
neutrophils, monocytes and plasma fatty free acids.
iii. Immune system is also compromised. Decrease in IgA, IgM and IgG while there is an increase of IgE.
iv. Decreased sperm counts and motility with presence of abnormal
morphology in male smokers.
10 commonly known errors in specimen collection
i. Misidentification of patient
ii. Mislabeling of specimen
iii. Short draws/wrong anticoagulant/blood ratio
iv. Mixing problems/clots
v. Wrong tubes/wrong anticoagulant
vi. Hemolysis/lipemia
vii. Hemoconcentration from prolonged tourniquet time
viii. Exposure to light/extreme temperatures
ix. Improperly timed specimens/delayed delivery to laboratory
x. Processing errors: incomplete centrifugation, incorrect log-in and improper storage.
When specimen is collected from patient with IV, the technologist should take note when it was decided to stop the IV lines. True or False?
True
Laboratory tests are often requested in the form of:
Electronically (using a computer thru LIS)
Writing (using a requisition form)
Verbal requests
The most error-free test ordering system
Electronically (using a computer thru LIS)
The clinician initiates the request for a laboratory measurement or examination using the LIS where the information is transmitted thru softwares or online means
Electronically (using a computer thru LIS)
The clinician initiates the request for a laboratory measurement or examination by completing a written order for desired laboratory measurements or examination in the patient’s medical record or chart
Writing (using a requisition form)
Test ordering system that is only done during emergency cases
Verbal requests
Clinical significance of timed specimen
Samples have to be collected at a specific time. Failure to follow the time schedule can lead to erroneous results and misinterpretation of a patient’s condition
Transcribe ASAP
As soon as possible
STAT means
Short Turn Around Time
Stat in American medical term meaning
Immediately
Stat is fom the Latin term
Statim
Although the definitions between laboratories may vary, stat means the
Highest priority in the workload
Purpose of timed specimens:
Monitor changes in patient’s condition
Determine the level of medication
Measure how well a substance is metabolized
Peak specimen are collected at
Varied times AFTER the drug was
administered
Trough specimen are collected at
30 minutes (may vary) BEFORE the
drug was administered
Most commonly observed collection-associated variable
Presence of the hemolysis in the sample
Hemolysis can be characterized by
Pinkish layer in the serum or plasma
Hemolysis is expected to occur in the following circumstances:
i. Transfixing of the vein
ii. Too small needle
iii. Expelling the blood vigorously into the tube
iv. Shaking or mixing the tubes vigorously
v. Performing blood collection before the alcohol has dried at the collection site
All specimens must be properly collected, labeled, transported and processed according to established procedures that include sample volume, special handling needs and container type. True or False?
True
The following are the reasons for specimen rejection:
a. Hemolysis/lipemia
b. Clots present in an anticoagulated specimen
c. Non-fasting specimen when test requires fasting
d. Improper blood collection tube
e. Short draws, wrong volume
f. Improper transport conditions (ice for blood gases)
g. Discrepancies between requisition and specimen label
h. Unlabeled or mislabeled specimen
i. Contaminated specimen/leaking container
Conditions that must be considered prior to transporting of specimens:
SLCPTT
a. Stability of the constituents
b. Label of the specimen
c. Container of the specimen used for transport
d. Potential infectious materials in the specimen
e. Temperature
f. Transport time
Ideally, all measurements should be performed within
45 minutes to 1 hour after collection
Blood should be stoppered in the original container until ready for separation. True or False
True
Preparation requirements for plasma preparation
Centrifuge blood within 1 hour after collection, for 10 minutes at a relative centrifugal force (RCF) of 850-1000×gravity (g)
Storage requirements for serum or plasma if analysis is to be delayed more than 4 hours
Must be stored at 4–6°C
A centrifuge uses _____ to separate phases of suspensions by different densities
Centrifugal force
Formula in computing relative centrifugal force (RCF)
𝑅𝐶𝐹=1.118 × 10^−5 ×𝑟 × 𝑟𝑝𝑚^2
For every laboratory procedure requiring centrifuge operation, a written specification identifying centrifuge type, temperature, the g forces required, and the length of centrifugation time is required. True or False?
True
Used for quality control of centrifuge
Tachometer or Strobe light
How often a centrifuge should be cleaned?
Every week
How often a centrifuge should be calibrated?
Every quarter
Loosening the clot by ‘trimming’ or ‘ringing’ the tube may cause some hemolysis and should be avoided. True or False?
True
