Chapter 10: Sample Preparation and Handling

Circadian

Cyclical changes throughout the day

Circannual

Seasonal changes over the course of a year

Cyclical

Occuring in cycles

Diurnal

Daily variation in blood levels at a particular time of day

Etiologic Agent

Viable microorganism or its toxin that causes or may cause human disease

Preexamination

All processes that it takes to collect the sample and get to the point in which the testing of the sample can occur

46-56%

Preexamination errors that occur prior to testing comprise how many percent of ALL errors encountered for laboratory samples?

Improper patient identification

What is the most serious and potentially most dangerous preexamination error?

Tourniquets

What is one factor under the phlebotomist’s control that can create a change in test results?

1 minute

The tourniquet should be on the arm no longer than?

Intervascular blood pressure

What does the tourniquet increase which results in a push of small molecules and fluid from the capillaries into the surrounding tissue?

Hemoconcentration

The reduction of fluid volume results in?

Potassium

The inability to circulate lowers the the pH and causes which analyte to be forced out of the blood cells?

Calcium and magnesium

The change in pH also causes an elevation in which two analytes?

Cell permeability

What will change in a patient if he or she has just completed vigorous exercise?

Creatinine kinase;

Aspartate aminotransferase;

Lactate dehydrogenase

Vigorous exercise causes an increase in concentration of:

1.) (?) (CK)

2.) (?) (AST)

3.) (?) (LDH)

4.) Bilirubin

5.) Creatinine

6.) Uric acid

Skeletal muscle

Lactate and pyruvate increase in even moderate exercise due to the increased metabolic activity of which muscle?

Runner's anemia

Long-term exercise by highly trained runners can cause which type of anemia?

2,000

Total WBC can increase by as much as much as (?) as a result of exercise or other stresses

Lactate

Which analyte is increased by 100% more when the patient makes an extremely tight fist or pumps the hand?

Hemoglobin

With the exception of this analyte, most analytes increase with exercise and stress

Creatinine kinase; Aspartate aminotransferase; Lactate dehydrogenase; Bilirubin; Creatinine; Uric acid; Lactate; Pyruvate; White blood cells; Neutrophils

Changes due to Exercise and Stress

List the 10 analytes increased

Glucose

Changes due to Exercise and Stress

List the analyte increased with stress but decreased with exercise

stress; exercise

Changes due to Exercise and Stress

Glucose is increased with (?) but decreased with (?)

Blood volume

Changes due to Posture

List the analyte decreased when changing from lying down to standing up

Blood pressure; Calcium; Cholesterol; Lipids; Drugs; Steroids; Thyroid hormones

Changes due to Posture

List the 7 analytes increased when changing from lying down to standing up

1 minute

After lying down, have the patient sit up for how long before you release him or her?

8-12 hours

Fasting usually means no food for how long?

morning

Fasting samples are generally collected in the (?) after an overnight fast

Water

The patient should not have had chewing gum, orange juice, or anything other than?

Glucose and triglycerides

Which 2 tests are affected when you collect a sample and label it as fasting when the patient was nonfasting?

No

Do fasting samples have a specific time for collection?

diurnal

Others tests may require that the sample be collected at a specific time because of medication or (?) rhythm

critical

For patients with diurnal rhythm or under medication, the precise timing of the collection for these samples is (?)

50%

Cortisol can vary as much as how many percent between samples collecting in the morning or evening?

morning

True or False? If false, replace the underlined word to make the statement correct.

“Serum iron levels are lower in the evening.”

Calcium

Which analyte demonstrates a circannual change, increases in the summer due to more sunlight exposure which results to increased Vitamin D?

75%

Most tubes should be filled at least how many percent of the stated volume to be accurate?

dilutional; decrease

If there is less blood in a tube, it causes a (?) effect, leading the RBCs to (?) in size

clot

If there is too much blood in an anticoagulant tube, it causes the blood to (?) because there is not enough anticoagulant for the volume of blood

Citrate tubes

Which tubes are the most critical for correct fill size?

10%

The variation in fill for citrate tubes can only plus or minus how many percent from the stated volume?

Draw another tube

When the blood tubes fill only partially, what must be done to obtain the proper amount?

poured

Partial tubes cannot be (?) together

doubled; altered

By pouring together partially filled tubes, the amount of anticoagulant in the tube is (?), resulting in (?) test results

mixed

Serum and plasma samples generally cannot be (?)

5-8

Inversion of (?) times must be done immediately after the tube is pulled from the holder

Ethylenediaminetetraacetic acid and Sodium citrate

Which are the 2 most sensitive tubes?

Sodium heparin

Chromosome studies need which type of heparin tube since lithium is toxic to cells?

syringes

The Clinical Laboratory Standards Institute (CLSI) guidelines discourage the use of (?)

Butterfly system

Difficult draws are best performed with a (?)

Evacuated tube system

What is the preferred method of collection?

Potassium; Phosphorous; Uric acid

Which 3 analytes are increased with the use of iodine?

alcohol pad

The iodine must be removed with an (?) if any testing other than a blood culture is collected

Nonalcohol cleaner

What must be used when cleaning a venipuncture site for blood alcohol testing?

Order of draw

Which is the most common factor that varies tests results that the phlebotomist has control over?

Prothrombin (PT) and Activated partial thromboplastin time (aPTT)

Which 2 test results can be increased if EDTA or Heparin tubes are drawn before the Citrate tube?

High

If the tube drawn after the EDTA is tested for potassium, will the potassium give a high or low result?

Dipotassium EDTA; Tripotassium EDTA

The EDTA used in the tube is either (?) or (?)

Ammonia;

Acid phosphatase;

Catecholamines;

Lactic acid;

pH/blood glases

List the 5 common tests requiring the chilling of specimens

Potassium; Serum potassium

What analyte is released when you chill an uncentrifuged serum tube? Which value does it elevate?

instructions

Only chill a sample when the draw (?) specifiy

Cold agglutinins; Cryoglobulin

What are the two tests that must be maintained at 37 degrees Celsius?

heel warmer

The best method of maintaining a sample 37 degrees Celsius is to wrap the sample in a (?)

warming block

Another method of maintaining a sample 37 degrees Celsius is to use a plastic block or (?)

amber tubes

Bilirubin samples must be collected in (?) to protect them from light

Vitamins C, E, K

Aside from bilirubin, what 3 other tests must be protected from light?

Wrap in aluminum foil

What is the most efficient method to protect the sample from light?

hand

If a heel warmer or warming block is not available, the sample can be bagged and held in your (?) as you transport it to the laboratory

label

Criteria for Recollection/Rejection of a Sample

Each sample must have its own (?) attached to the sample's primary container.

test to be performed

Criteria for Recollection/Rejection of a Sample

Each sample must have on the label the name of the (?) (e.g., complete blood cell count [CBC], cholesterol).

complete name; hospital number

Criteria for Recollection/Rejection of a Sample

Labels must have the patient's (?) and (?) or unique identifier.

time limits

Criteria for Recollection/Rejection of a Sample

The sample must be collected within the (?) requested.

removed; capped

Criteria for Recollection/Rejection of a Sample

Samples in syringes must have needles (?) and the syringe (?) before transport.

container; lid

Criteria for Recollection/Rejection of a Sample

Urine samples must have the label on the (?) and not on the (?).

appropriate

Criteria for Recollection/Rejection of a Sample

The (?) anticoagulant must be used for samples requiring an anticoagulant.

expiration date

Criteria for Recollection/Rejection of a Sample

Tubes may not be used beyond the (?).

light

Criteria for Recollection/Rejection of a Sample

Certain samples may not be exposed to (?).

clots

Criteria for Recollection/Rejection of a Sample

Anticoagulated blood samples must be free of (?).

unacceptable

Criteria for Recollection/Rejection of a Sample

Blood samples drawn above an intravenous (IV) injection site are (?).

Primary container

What do you call the container in which the sample was collected?

secondary container

When a sample is transported, the primary container must be placed in a (?)

Plastic self-sealing bag

Which type of secondary container is sufficient for most samples?

True

True or False? If false, replace the underlined word to make the statement correct.

“A single sample or multiple samples from one patient can be placed in the bag and then the bag sealed shut. However, samples from different patients should not be placed in the same bag.”

before

True or False? If false, replace the underlined word to make the statement correct.

“All labels must be attached to the sample tubes after they are placed in the bag.”

Biohazard emblem

Whatever secondary container is used, which emblem must be attached?

faster delivery

Pneumatic tube systems that transport samples are more traumatic than hand carrying the samples but have the advantage of (?)

padded container

What can be done to prevent trauma to the sample?

—the bagged sample is placed into a (?) to maintain the integrity of the sample

requisition

The self-sealing bags for these specimens have two compartments.

One compartment is for the sample and the other compartment is for the (?).

leak

Separate compartments prevent the requisition from being contaminated if the sample tube should (?)

absorbent

etiologic agent

The outside of the shipping container must have the biohazard emblem and wording that the container holds an (?) (infectious substance).

Federal Aviation Administration (FAA)

(?) and other government agencies regulate the shipment of etiological agents.

Category A; Category B

What are the 2 categories of infectious substances?

Category A

An infectious substance which in a form that, when exposure to it occurs, is capable of causing permanent disability, life-threatening or fatal disease in otherwise healthy humans or animals.

UN2814

What is the proper shipping name for Category A (infectious substances, affecting humans)?

UN2900

What is the proper shipping name for Category A (infectious substances, affecting animals)?

Category B

An infectious substance which does not meet the criteria for inclusion in Category A.

UN3373

What is the proper shipping name for Category B

Category B

What is the classification of clinical specimens requested in support of a VS acute gastroenteritis outbreak investigation?