Blood Collection Flashcards
Angle between skin and needle in venipuncture
<30 degrees
Effects of prolonged tourniquet application
SHH
- Hemoconcentration
- Hemolysis
- Shortened coagulation times (PT, APTT)
Order of preference in venipuncture
- Median cubital vein
- Cephalic (for H) / Cephalic Accessory vein (for M)
- Basilic vein
Order of draw in skin puncture
TSEOS
- Tube for blood gas analysis
- Slides
- EDTA microcollection tube
- Other microcollection tubes with anticoagulant
- Serum microcollection tubes
Recommended depth of skin puncture for infants and adults
Infants <2mm
Adults 2.0-2.5mm
Test results affected by posture
PIC
- Protein
- Iron
- Cholesterol
Treat all body fluids and unfixed tissues as potentially infectious
Standard precautions
–> originally called as Universal Precautions
What is the most common needle size for adult (give the bore and length)
Bore: 21 G
Length: 1 inch
Which has a larger bore? 19G / 21G
19G
The most common cause of needle puncture
Improper disposal of sharps
When to replace the sharps container?
When they are no more than three-quarters full.
Flat, purplish discoloration of the skin
Ecchymosis
Bulging, purplish, discoloration
Hematoma
How many minutes should you wait to draw the blood of the patient if there is a prolonged application of the tourniquet?
2 minutes
Where will you draw the blood of patients undergoing IV therapy if both arms are unavailable?
- Ask the nurse to stop the IV infusion for 2 min.
- Draw blood BELOW the IV site
- Discard the first 5mL of blood collected
BF cuff used as a tourniquet for obese patients should NOT be inflated for how many mmHg?
> 40 mmHg and NOT left on the arm for more than 1 min
Anemia caused by blood loss for testing
Iatrogenic anemia / Physician induced-anemia/ Nosocomial anemia
Skin puncture is a technique of choice to obtain blood specimens from the ff. EXCEPT
a. Newborns and Pediatric patients
b. Severely burned patients
c. Patients whose veins are reserved for therapeutic purposes
d. Extremely obese patients
e. Elderly patients
All of the above
The puncture site for infants who are <1 y/o is the _
Medial / lateral side of the heel
Why is it necessary to discard the first drop of blood?
- To discard excess tissue fluid
- To discard dead epidermal cells
- To facilitate flow of blood
The ideal puncture site for children (>1 y/o) and adults
Palmar surface of the non-dominant hand, 3rd/4th finger, distal portion (perpendicular to the fingerprint)
Warming the puncture site can increase the blood flow _ fold
sevenfold
The site can be warmed using a warm wash cloth of (_ to _ C) for no longer than _ min
40-42C for no longer than 3-5 min.
What is the first tube to be collected for skin puncture?
Tube for blood gas analysis
What is the first microcollection tube to be collected for skin puncture
EDTA microcollection tube
What is the most common skin antiseptic
70% Isopropyl alcohol
What is the most common site for venipuncture
Superficial veins of the antecubital fossa
It is the condition wherein venous flow is slowed
Stasis
–> results in the local accumulation of Factor VIII and vWF
Distance of tourniquet above the venipuncture site
3-4 inches / 7.5-10 cm
A phlebotomist must never puncture a patient _
twice
–> Endorse the patient to another phlebotomist if failed to collect 2x
Patients should not pump the fist as it may elevate _ concentration
Potassium
Areas to avoid in venipuncture
VVFAIE
- Veins in the inner wrist
- Veins in the feet
- Fistula
- Arteries
- Inflamed sites
- Edematous sites
What is NOT a cause of specimen hemolysis?
a. Application of tourniquet for 45 sec.
b. Moisture from alcohol
c. Contamination in the collection tube
d. Needles with TOO SMALL bores
e. Excessive agitation
f. Frothing of the sample
A
Sharps containers must be replaced when they are no more than _ full
Three-quarters full
It is the most common complication encountered in performing venipuncture
Ecchymosis
A short lapse in consciousness
Syncope/ Fainting
What should be done if a patient experiences syncope?
Call a physician immediately and give patient sufficient air