Chapter 31 : Phlebotomy Flashcards

Question

What are the three main components of anticoagulated blood after centrifugation?

Answer 1

Plasma, buffy coat, red blood cells

Answer 2

Young : Yellow - SPS - Cultures Little : Light Blue - Sodium Citrate - Prothrombin Time (PT , PT/INR) Rude : Red or SST [Red Gray (tiger)] - No additive (SST has gel to separate serum) - Chemistry Girls : Gold (SST) - No additive - Chemistry Get : Green - Heparin - Blood Gas , PH Assay Low : Lavendar - EDTA - CBC (erythrocite, sedimentation - ESR sed rate -> check inflammation Grades : Gray - Sodium Flouride , Potassium Oxlate - OGTT

Answer 3

Purpose of phlebotomy: Collect blood for laboratory analysis -- Phlebotomy: Incision of a vein for the removal of blood -- Phlebotomist: Individual collecting the blood sample

Answer 4

Tested at the office - Taken to an outside laboratory for testing * Must be placed in a biohazard specimen bag Taken to an outside laboratory for testing * Needs to be accompanied by a laboratory request * Informs laboratory what tests to run—MA completes laboratory request: on computer; manually (by hand)

Answer 5

Performed in a hospital setting— to assess blood for: * Oxygen level * Carbon dioxide level * Acid-base balance MA's do not perform

Answer 6

Puncturing of a vein for the removal of a venous blood sample -- Performed when a large blood specimen is needed for testing 3 Methods 1. Evacuated - AKA Vacuum -- fastest, most convenient, most often used 2. Winged Infusion Set AKA Butterfly 3. Syringe E needle (last two are for difficult draws, small veins, sclerosed (hardened veins)

Answer 7

- Verify any advance preparation - Review specimen collection and handling requirements - Identify the patient - Reassure the patient - Assemble equipment and supplies - Position the patient - Apply tourniquet - Select a site for venipuncture - Obtain type of blood specimen required - Follow Occupational Safety and Health Administration (OSHA) Bloodborne Pathogens Standard

Answer 8

Instruct patient to remain still - Tell patient that a small amount of pain is associated with the procedure - Never tell the patient that the VP will not hurt Just before inserting the needle, tell patient he or she will “feel a small stick” - Avoids startling the patient: Could cause patient to move * Movement causes pain * Could damage VP site

Answer 9

Most common VP site - Patient should be seated in a chair - Arm extended in downward position—to form straight line from shoulder to wrist * With palm facing up * Arm should not bend at elbow - Arm should be well supported on the armrest * By rolled towel * By patient placing fist of the other hand under the elbow If patient has fainted in the past from VP or is nervous -- Place in a semireclining position on the examining table

Answer 10

Blood flows from evacuated tube back into patient’s vein during the procedure - Could cause patient to have adverse reaction to a tube additive * Particularly EDTA - To prevent: Keep patient’s arm in a downward position * Evacuated tube remains below the VP site—fills from the bottom up

Answer 11

Makes patient’s veins stand out so that they are easier to palpate. Causes venous blood to slow down and pool. in veins in front of tourniquet - Makes veins more prominent * More visible * Can be palpated When applying: Important to obtain correcttension - Should slow venous flow without affecting arterial flow - Too tight: Obstructs arterial and venous flow * May produce inaccurate test results Too loose: Veins do not stand out enough to be palpated - Correct tension * Should fit snugly * Not pinch skin Do not apply over sores or burned skin - Place 3 to 4 inches above bend in elbow - Allows adequate room for: * Cleansing site * Performing VP

Answer 12

Apply treatment so that it is snug - Should not pinch patient’s skin - Should not be painful to patient - Ask patient to clench fist: Pushes blood from lower arm into veins for easier palpation -- Ask patient to clench and unclench fist a few times * Avoid vigorous pumping: Could lead to hemoconcentration Never leave on for more than one minute - Uncomfortable for patient - Causes venous blood to stagnate: Venous stasis * Plasma filters into tissues: Causes hemoconcentration Remove tourniquet when good blood flow is established - When first learning venipuncture: Best to remove tourniquet just before removing needle—may move needle * No more blood flow * Must redraw Always remove tourniquet before removing needle - If needle is removed first, blood is forced out of the puncture site causing a hematoma - Hematoma: A swelling or mass of coagulated blood caused by a break in a blood vessel Wipe tourniquet with a disinfectant (alcohol) if reusable - Throw away if disposable

Answer 13

An increase in the concentration of blood components * Caused by a decrease in the fluid content of the blood * Can alter test results

Answer 14

Flat, soft band of rubber - One inch wide - 15 to 18 inches long - Advantage: Easily removed with one hand Position - 3 to 4 inches above bend in elbow - Should lie flat against patient’s skin - Flaps must be directed upward so that they do not dangle in working area

Answer 15

Band of rubber or elastic with Velcro attached at the ends Advantages -- Easier to apply than a rubber tourniquet -- More comfortable for patient Disadvantages - More difficult to remove - May not fit around arm of obese patients

Answer 16

Best site for most patients: Veins in antecubital space - Easy to draw blood * Patient with large visible veins - Difficult to draw blood * Small veins * Veins that cannot be palpated

Answer 17

Usually have wide lumen Close to surface of skin * Makes them easily accessible Usually have thick walls * Less likely to collapse Skin is less sensitive * Less pain for patient Do not use small spidery veins on the surface of skin - Not suitable for VP - Antecubital veins lie beneath these veins

Answer 18

1. Median Cubital (Best vein) -- Large vein: Does not roll Located in middle of antecubital space—cannot be used * When it lies deep in the tissues: Cannot be palpated * Is scarred from repeated VPs 2. Cephalic (Does not roll) 3. Basilic Basilic and cephalic: Located on opposite sides of antecubital space * Use: When median cubital cannot be used * Cephalic: Located on thumb-side of hand * Basilic: Located on little-finger side of hand * Disadvantage: May roll and escape puncture—to prevent, apply firm pressure below vein to stabilize it - Cephalic: Second choice * Does not roll and bruise as easily as basilic - Basilic: Last choice—may cause injury to underlying structures * In some individuals, branches of median nerve lie close to basilic * Lie in close proximity to the brachial artery

Answer 19

Also located in antecubital space (used to measure BP) - Lies deeper in the tissues - Artery pulsates, is more elastic, and has a thicker wall than a vein - If punctured: Patient feels more pain and blood is bright red and comes out pulsing—if this occurs: * Remove tourniquet and then needle * Apply pressure with gauze pad for 4 to 5 minutes

Answer 20

- Ensure adequate lighting - Ensure that veins “stand out” as much as possible - Examine antecubital veins of both arms - Use inspection and particularly palpation to select a vein -- Vein does not have to be seen to be a good selection -- Palpation alone can be used to locate a vein -- Vein feels like an elastic tube * Gives under the pressure of the fingertips - Palpate for the median cubital vein first -- Advantages over other antecubital veins * Usually bigger * Anchored better * Bruises less * Poses smallest risk of injuring underlying structures (nerves) - Thoroughly assess vein -- Place one or two fingertips over vein * Index and middle finger -- Press lightly, then release pressure -- Do not use thumb to palpate (not as sensitive) -- Suitable vein feels round, firm, elastic, and engorged * When an engorged vein is depressed and released, it springs back in a rounded, filled state - Determine size, depth, and direction of vein -- Thoroughly palpate vein -- Trace the path of the vein * By rolling the index finger back and forth over vein -- Inspect and palpate vein for problems * Small * Hard * Bumpy * Flat - Mentally “map” puncture site on patient’s arm with skin marks -- Site may be near freckle, wrinkle, or pigmented area -- Helpful in making stick when vein cannot be seen and can only be palpated - Do not leave tourniquet on for more than one minute - Causes: * Patient discomfort * Hemoconcentration Techniques to make veins more prominent - Remove tourniquet and have patient dangle arm over side of chair for 1 to 2 minutes - Tap vein site sharply with index finger and second finger - Gently massage arm from wrist to elbow - Apply warm, moist washcloth for five minutes

Answer 21

Inner forearm Wrist area above thumb Back of hand Smaller than antecubital veins Have thinner walls Use alternative veins when all possibilities at the antecubital site have been considered Example: May be able to use butterfly on a small antecubital vein Use veins in hands as a last resort - Have a tendency to roll because: * Not supported by much tissue * Close to the surface of the skin—makes them more difficult to stick - Abundant supply of nerves in hand * Makes procedure uncomfortable for patient - Thin walls—make them susceptible to: * Collapsing * Bruising * Phlebitis In some patients, hand veins may be only accessible site - Examples * Obese patients * Elderly patients

Answer 22

Examples * Serum: Required for most blood chemistry studies * Whole blood: Required for a complete blood count (CBC)

Answer 23

Obtained from tube with no anticoagulant -- Causes blood cells to clot

Answer 24

Obtained from clotted blood - Allow specimen to stand and then centrifuge it - Because tube does not contain an anticoagulant, separates into: * Top layer: Serum * Bottom layer: Clotted blood cells

Answer 25

Obtained from tube containing an anticoagulant to prevent clotting of blood cells - Tube must be gently rotated 8 to 10 times after collection * To mix anticoagulant with blood

Answer 26

Obtained from whole blood that has been centrifuged - Because tube contains an anticoagulant, separates into: * Top layer: Plasma * Middle layer: Buffy coat (white blood cells and platelets) * Bottom layer: Red blood cells (RBCs)

Answer 27

When an anticoagulant is added to the specimen - Plasma - Buffy coat - Cells When an anticoagulant is not added to the specimen - Serum - Cells (clot)

Answer 28

- Collection needle - Plastic needle holder - Evacuated tube

Answer 29

Needle consists of: - Anterior needle: Is longer and has a beveled point * Bevel: Facilitate entry into skin and vein Posterior needle: Pierces rubber stopper of evacuated tube—needle has a rubber sleeve that functions as a valve * When tube is removed, sleeve slides back over needle opening—closes off opening; stops flow of blood

Answer 30

20 TO 22 (most common) 21 gauge: Most commonly used 22 gauge: Recommended for children and adults with smaller veins 20 gauge: When a large volume tube is used

Answer 31

1 inch and 1½ inches - Length used based on individual preference * 1 inch: Less intimidating to patient; offers more control during stick * 1½ inch: Allows more room for stabilizing the vein

Answer 32

OSHA stipulates requirements - To reduce needlestick and other sharps injuries among health care workers Employers must evaluate and implement safer medical devices Have built-in safety features to reduce risk of needlestick injuries

Answer 33

Consists of plastic cylinder with two openings - Small opening: Used to secure needle - Large opening: Holds evacuated tube

Answer 34

Extension on large opening - Assists in insertion and removal of tubes - Prevents holder from rolling when placed on a flat surface

Answer 35

Marks point at which the posterior needle starts to enter rubber stopper of tube * Do not insert tube stopper past this point before entering the vein—causes tube to fill with air; blood is not able to enter the tube

Answer 36

Glass tube with: - Rubber stopper - Hemogard closure stopper Contains vacuum that creates suction - Pulls blood specimen into tube Tube additive must not: - Alter blood components - Affect laboratory test

Answer 37

Red : Does not contain an anticoagulant -- Used to obtain clotted blood or serum Serum required for: * Immunologic tests * Most blood chemistries Red/gray speckled tube (“tiger-top”) : Does not contain an anticoagulant, Gold stopper: If using Hemogard tubes, Used to obtain serum. -- Gold stopper: If using Hemogard tubes * Contains a clot activator—makes RBCs clot more quickly to yield serum: Invert tube 5 times after drawing to mix clot activator with specimen * Also contains a gel—separates cells from serum when tube is centrifuged Lavender: EDTA (anticoagulant) - Used to obtain whole blood or plasma - Most common use: Collect a blood specimen for a CBC Light blue: Sodium citrate (anticoagulant) - Used to obtain whole blood or plasma - Most common use: Coagulation tests (e.g., prothrombin time) Green: Heparin (anticoagulant) - Used for blood gas determinations and pH assays - Gray: Sodium fluoride/potassium oxalate (anticoagulant) - Used to obtain whole blood or plasma - Most common use: OGTT Royal blue: EDTA or no additive - Made of refined glass and a special stopper - Used to detect trace elements (e.g., lead, arsenic)

Answer 38

Range between 2 mL and 10 mL

Answer 39

Additive content - Expiration date - Tube capacity - Fill indicator * To indicate when vacuum has been exhausted—tube is full

Answer 40

Consists of rubber stopper with a plastic closure that overhangs outside of tube * Acts as a single unit to reduce the likelihood of coming in contact with contents of tube If need to gain access to blood in tube (e.g., testing, further processing) * Prevents splattering of blood Conventional rubber stopper-evacuated tube; pops as top is removed Color coding is similar to rubber-stoppered tubes

Answer 41

breakdown of red blood cells

Answer 42

Plasma from which the clotting factor fibrinogen has been removed - Normally clear and yellow - Serum contains dissolved substances -- Glucose -- Cholesterol -- Lipids -- Sodium -- Potassium -- Chloride -- Antibodies -- Hormones -- Enzymes

Answer 43

- Serum recovered is only part of total blood specimen -- Must use a tube that is 2½ times amount required for test * Example: To obtain 2 mL of serum—must use a 5-mL red-stoppered or SST tube (2 × 2½ = 5)

Answer 44

- Allow tube to stand upright at room temperature for 30 to 45 minutes -- Allows clot formation; yields more serum - If centrifuged immediately: -- Clotting factors do not have time to settle into cell layer -- Result in formation of a fibrin clot in the serum layer * Spongy substance that occupies space * Interferes with adequate serum collection - Do not let blood stand for more than one hour - Leaching of substances from cell layer into serum * Leads to inaccurate test results

Answer 45

After allowing specimen to stand, centrifuge specimen for 10 minutes Red stopper tube: Remove serum with a pipette and place it in transfer tube - Do not disturb cell layer of the clot * Draws RBCs into serum layer - If cells enter serum, recentrifuge the specimen Hold serum up to light to inspect for the presence of: - Intact RBCs - Hemolyzed blood - If present, specimen has a reddish appearance * Must recentrifuge After centrifuging intact RBCs - Cells settle to bottom of tube - Serum can be removed After centrifuging hemolyzed blood - Serum will still have a reddish appearance * RBCs have ruptured * Releases hemoglobin into serum - Not suitable for laboratory tests; inaccurate test results - Must collect another specimen

Answer 46

Thixotropic gel

Answer 47

Also called capillary puncture Skin puncture performed when test requires small amount of blood - Preferred for infants and young children * Venipuncture is difficult to perform on children in these age groups - Adult has no acceptable veins (as a last resort)

Answer 48

- Third or fourth finger - Earlobe is no longer recommended * Blood in earlobe contains a higher concentration of hemoglobin than fingertip * Slower flow of blood makes it harder to collect specimen

Answer 49

Plantar surface of heel - Never perform finger puncture on an infant * Amount of tissue between skin and bone is small—injury to bone is likely - After child is walking—can perform on fingertip

Answer 50

Types - Disposable semiautomatic retractable lancet device - Reusable semiautomatic retractable lancet device

Answer 51

Adults: Must not be deeper than 3.1 mm Infants (heel) and children: Must not be deeper than 2.0 mm

Answer 52

Could result in: * Osteochondritis: Inflammation of bone and cartilage * Osteomyelitis: Inflammation of bone due to bacterial infection - To prevent, use spring-loaded blade available in different lengths to control the depth of the puncture

Chapter 31 : Phlebotomy Flashcards

(103 cards)