Medical Laboratory Science Practice Flashcards

Flashcards for reviewing medical laboratory science practices.

When should alcohol-based sanitizers be used?

When hands are not visibly contaminated.

List the materials needed for proper handwashing.

Antimicrobial soap, paper towels, running water, and a waste container.

How long should hands be scrubbed during proper handwashing?

At least 15-20 seconds, ensuring all surfaces are scrubbed, especially between fingers and knuckles.

Describe the correct order for donning PPE.

Gown first, mask next, and gloves last. Goggles, respirators, and face shields are worn after the mask but before the gloves.

Describe the correct order for doffing PPE.

Gloves first, gown next (removing from shoulders toward the hand), and mask last (holding only the string). Goggles, respirators, and face shields are removed after the gloves.

What is venipuncture?

The act of entering a vein to obtain a blood sample.

Name the three methods of obtaining blood samples.

Venipuncture, arterial puncture, and capillary puncture.

What is the purpose of the safety shield in an Evacuated Tube System (ETS)?

To cover the needle and prevent needle prick injuries.

What is the stopper-puncturing end of a needle?

The part of the needle that is inserted into the rubber of the blood tube.

What does needle gauge refer to?

The diameter of the needle bore (hole of the needle).

Explain why multisample needles have a rubber sheath.

The rubber sheath prevents leakage of blood when tubes are being changed.

What are needle holders also called?

"Adapters"

What are evacuated tubes also known as?

Vacutainers

What does the red-stoppered collection tube indicate?

No anticoagulant; it is meant to prepare serum specimens for clinical chemistry analysis.

What is the purpose of a blood transfer device?

To provide a safe means for blood transfer without using the syringe needle or removing the tube stopper.

What are winged blood collection sets also known as?

"Butterflies"

What is the primary antiseptic used for cleansing the skin in routine phlebotomy?

70% isopropyl alcohol

Why are cotton balls not recommended for applying pressure to a venipuncture site?

Because the cotton ball fibers can stick to the venipuncture site and may cause bleeding to begin again when the cotton is removed.

Where should heel punctures NOT be performed on infants younger than 1 year?

Other areas of the foot, particularly not in the arch.

What is the recommended temperature range for warming a dermal puncture site?

42-42°C

What are the consequences of failing to allow alcohol to dry on the skin before a dermal puncture?

Causes a stinging sensation for the patient, contaminates the sample, hemolyzes RBCs, and prevents formation of a rounded blood drop.

Why is the first drop of blood wiped away during a dermal puncture?

To prevent contamination of the sample.

How should micropipettes be held to prevent air bubbles?

Horizontally

How are microcollection tubes positioned during blood collection?

Slanted down, allowing blood to run through the capillary collection scoop and down the side of the tube.

Why is it important to work quickly during microcollection?

Blood that takes more than 2 minutes to collect may form microclots in an anticoagulated microcollection container.

What steps should be taken after microsamples are collected?

Apply pressure to the puncture site, elevate the finger or heel, and confirm that bleeding has stopped before removing the pressure.

List essential equipment to prepare for Phlebotomy.

Requisition form, gowns and gloves, extensive hand washing, and only take nessecary equipment to the patient.

What is the first step in the venipuncture procedure?

Obtain and examine the requisition form.

What position should the patient's arm be in during venipuncture?

Slightly bent in a downward position so that the tubes fill from the bottom up. Do not let the patient hyperextend the arm.

How many inches above the antecubital fossa should the tourniquet be applied?

The tourniquet should be applied 3 to 4 inches above the antecubital fossa.

Describe the cleansing motion when cleaning the venipuncture site.

Clean the site with 70 percent isopropyl alcohol in concentric circles moving outward and allow it to air dry.

At what angle should the needle be inserted during venipuncture?

15 to 30 degree angle with the bevel up until you feel a lessening of resistance.

List reasons for rejecting a urine specimen.

Specimens in unlabeled containers, nonmatching labels and requisition forms, specimens contaminated with feces or toilet paper, containers with contaminated exteriors, specimens of insufficient quantity, and specimens that have been improperly transported.

How should urine specimens be stored if they cannot be tested within 2 hours?

Refrigerated or have an appropriate chemical preservative added.

What is the normal odor of freshly voided urine?

Faint aromatic odor

What are reagent strips?

Chemical-impregnated absorbent pads attached to a plastic strip.

List factors in the care of reagent strips.

Store with desiccant in an opaque, tightly closed container. Store below 30 °C; do not freeze. Do not expose to volatile fumes. Do not use past the expiration date. Do not use if chemical pads become discolored. Remove strips immediately prior to use.

How often should open bottles of reagent strips be tested with known controls?

Every 24 hours

What is the normal pH range for random urine samples?

4.5 to 8.0

What is the clinical significance of urine pH?

Respiratory or metabolic acidosis/ketosis, respiratory or metabolic alkalosis, defects in renal tubular secretion and reabsorption of acids and bases, renal calculi formation, treatment of urinary tract infections, precipitation/identification of crystals, and determination of unsatisfactory specimens.

What is the protein level in normal urine?

<10 mg/dL or 100mg per 24 hours

What does the presence of glucose in urine indicate?

Detection and monitoring of diabetes mellitus

What three intermediate products of fat metabolism are represented by ketones?

Acetone, acetoacetic acid, and beta-hydroxybutyric acid

What can ketonuria show?

A deficiency in insulin, indicating the need to regulate dosage.

What is bilirubin?

An early indication of liver disease.

What does nitrite in urine indicate?

A rapid screening test for the presence of urinary tract infection (UTI)

What does an elevated specific gravity mean?

More solutes

What volume of urine is centrifuged for microscopic examination?

10 and 15mL

List reasons for rejecting a stool specimen.

Specimens in unlabeled containers, nonmatching labels and requisition forms, specimens contaminated with urine or toilet paper, containers with contaminated exteriors, specimens of insufficient quantity (pea-sized), and specimens that have been improperly transported.

What are three physical properties related to physical examination of stool specimens?

Consistency, color, and gross abnormalities

What does the presence of mucus, blood streak indicate in stool specimens

Dysentery and malignancy.

How is fecal occult blood (FOBT) detected?

Hema Screen Guiac Slide Test Kit

What is a screening method?

Simple, Rapid, and Inexpensive test used for good analytical sensitivity and marginal specificity

List Screening methods

Gas chromatography - Mass Spectometry (GC-MS), Chromogenic Reactions, Immunoassay based procedures, and Thin-Layer Chromatography.

What is one advantage of saliva when being drug tested?

Recent Drug use, Non-invasive , Concentration well correlated with blood, and Difficult to adulterate

What is Meconium

Amniotic Fluid, mucus, bile, and cells passed within 24-48 hours for detection of drugs during pregnancy

What is the purpose of the Evacuated Tube System (ETS)?

To obtain a blood specimen for patient diagnostic or monitoring purposes from an antecubital vein using the evacuated tube system (ETS)

Name some equipment needed for Winged Blood Collection set

Requisition form, Gloves ,Tourniquet, Isopropyl alcohol pad, Blood transfer device, Evacuated tubes, gauze , Sharps container, pen Bandage, and Biohazard bag

define Centrifuge.

An instrument that spins blood tubes at a high relative centrifugal force to separate serum or plasma from the blood cells

What are three classifications of a support medium?

solid, liquid, or semi solid designed to support the growth of microorganisms

What is Autoclaving?

exposure to steam at 121°C and 15lbs of pressure for 15 minutes or longer, depending on the nature of the item.

Name the 13 histopathologic techniques in the order they are performed.

Numbering, Fixation, Decalcification, Dehydration, Clearing, Wax impregnation, Embedding, Blocking, Trimming, Sectioning, Staining, Mounting, and Labelling

Name miscellaneous info needed on a Specimen source.

age, sex, ward

Ideal size for Light Microscopy

2cm² ..

Which fixative has lipids that don't preserve well under it?

Formalin

Explain Chromate Fixatives

3% Aqueous Solution Preserves Lipids

What does Trimming refer to?

Process of removing excess wax after embedding - Can use knife/blade or heated spatula

Clear embedded secretions in

xylene bath

What does coagulation measure

time

Duke Method Reference range

1 to 3 minutes

Define clotting factor.

Group of proteins that will work after the platelets have attempted to repair blood vessel damage

State the responsibility of Blood bank in medicine

To provide a safe, sufficient, and timely supply of blood and blood products & Ensure that the act of blood donation is safe and causes no harm to the donor

Describe age limits when donating Blood.

Lower age limit: 18 years (age 16 or 17 years needs parental permission) & Upper age limit: between 60 and 70 years

State Hemoglobin level needed when donating Blood.

At least 12.5 g/dL

Explain what it signifies when a blood drop doesn't sink

If the drop of blood floats or suspends, the hemoglobin level is estimated to be <12.5 g/dL

• causes: menstruation, anemic