CC PART 8 (PHLEBOTOMY SOURCES OF ERROR) Flashcards
● Treatment error, possibility of
transfusion fatality
Misidentification patient
● Treatment errors if samples for
certain tests aren’t drawn at appropriate time.
● Ex. Therapeutic drug monitoring, analytes that exhibit diurnal variation, analytes that require fasting
Drawing at incorrect time
● ____________________________ =
antiseptic used in ethanol testing
○ Non-alcohol based
Benzalkonium Cl or Zephiran
● Infection at site if puncture.
Contamination of blood culture
and blood components
● Isopropyl alcohol wipes can
contaminate samples for blood
alcohol
Improper skin disinfection
Cleaning of site:
Up and Down motion (CLSI)
● Dilution of sample with tissue
fluid
Drawing from edematous site
● Increase K+ , lactic acid, Ca2+ ,
phosphorus, decreased pH
Fist pumping during venipuncture
● Increase K+ , total protein, lactic
acid
Tourniquet > 1 minute
● Increase glucose, electrolytes
● For 10-15% contamination of
Dextrose 5% in Water (D5W)
the glucose ↑ by up to 500
mg/dL
IV fluid contamination
● Decreased vacuum, failure to
obtain specimen
Expire collection tubes
● K2 EDTA before serum or
heparin tube:
● Decreases Ca & Mg, Increase
K+
● Contamination of citrate tube
with clot activator: erroneous
results of PT and APTT
Incorrect anticoagulant or
contamination from incorrect order of draw
● Sodium Heparin: Increase Na
● Lithium Heparin: Increase
Lithium
● Gel separator: Decreases
Tricyclic Antidepressants and
trace metals
Incorrect anticoagulant or
contamination from incorrect order of draw
● Carryover from one tube to
another.
● Possible additive contamination
Failure to hold bottom of tube
lower than top during collection
● Incorrect blood: anticoagulant
ratio affects some results like PT
and APTT
Short Draw
● Micro-clots fibrin, platelet
clumping can lead to erroneous
results
Inadequate mixing of anticoagulant tube
Hemolysis from alcohol contamination, “__________-” site of capillary puncture, probing with needle, vigorous shaking of
tubes, exposure of samples to extreme temperature
milking
What is antiseptic used in ethanol testing?
Benzalkonium Cl or Zephiran
What analyte is significantly affected by repeated and vigorous fist exercise during
venipuncture causing falsely increased levels?
A. Potassium
B. Sodium
C. Magnesium
D. Calcium
A. Potassium
Which of the following is not used as antiseptic during venipuncture?
A. Benzalkonium chloride
B. Sodium Hypochlorite (Zonrox)
C. Gauze
D. 70% alcohol
B. Sodium Hypochlorite (Zonrox)
Gauge for Adult patients
21
What is the effect on draw volume if evacuated tubes are stored at high temperatures?
A. Decrease
B. None
C. Indeterminate
D. Increase
A. Decrease
If blood was collected using an anticoagulant how would the volume of plasma be usually
described compared to blood collected without the anticoagulant and serum is obtained instead?
A. Same
B. Lower
C. Greater
D. Indeterminate
C. Greater
Gauge for Pediatric patients = __, if not in the choices 22
23
● Tube Size
- Pedia: ___ uL
- Adult: up to ___ mL
- Pedia: 150 uL
- Adult: up to 7 mL
ORDER OF DRAW
ETS
B C N H E S
● B = Blood culture
● C = Citrate
● N = Non-additive
● H = Heparin
● E = EDTA
● S = Sodium Fluoride
ORDER OF DRAW
Syringe
B C H E F R
ORDER OF DRAW
Capillary Puncture
E O S
ORDER OF DRAW
Catheter/ Central Venous Access
B A P
Professionalism, Patient consent (implies consent), legal issues, infection control (PPE, hand hygiene, isolation)
PUBLIC RELATIONS AND CLIENT INTERACTION
The inner layer composed of a lining of epithelial cells
Tunica intima
The middle layer composed of smooth muscle and elastic tissue
Tunica media
The outer layer composed
Tunica adventitia/ externa
Heart to body cells
Arterial Blood
Larger oxygen concentration
Arterial Blood
Color: Bright Red
Arterial Blood
Heart to lungs
Venous Blood
Color: Dark Red
Venous Blood
Larger carbon dioxide concentration
Venous Blood
- Median Cubital Vein- ___ choice
- Cephalic vein- ___ choice
- Basilic vein - ___ choice
- Median Cubital Vein- 1st choice
- Cephalic vein- 2nd choice
- Basilic vein - 3rd choice
Tourniquet: ____ inches above the site, not more than
minute
3-4
VENOUS BLOOD COLLECTION
● Needle insertion:
15-30 degree angle
Deoxygenated, Dark Red color
VENOUS BLOOD COLLECTION
○ Luer fitting for _________
○ Luer adapter for _______
○ Luer fitting for syringe
○ Luer adapter for ETS
○ 6-9 inches long
○ 23 gauge
○ 10-15 degree angle
○ Use butterfly to: small fragile veins, pediatric, geriatric patients
○ Disadvantage: Prone to hemolysis
Winged Infusion Set (Butterfly)
The needle gauge used in pediatric venipuncture is:
A. 20
B. 22
C. 21
D. 19
B. 22
How many inches above the site of venipuncture should the tourniquet be placed?
A. 3-4 inches
B. 1-2 inches
C. 2-3 inches
D. 4-5 inches
A. 3-4 inches
What is the length of the most common used needle in inches for routine venipuncture?
A. 0.5-1.0
B. 1.0-1.5
C. 1.5-2.0
D. 2.0-2.5
B. 1.0-1.5
● For Arterial Blood Gas (ABG) analysis and pH measurements
● No tourniquet needed
● Oxygenated, Bright Red Color
ARTERIAL
● Common sites: Arteries—- Radial, Brachial, Femoral, Scalp
● Angle: 30, 45, 90 degree
ARTERIAL
● Before collecting blood you should do the _______ to
check the blood flow
● Major Complications: Thrombosis, Hemorrhage and
infection
ARTERIAL
Allen’s Test
● Discard the first drop; do not milk the site
● < 1 year old: Lateral plantar heel
CAPILLARY
● Older: Palmar surfaces of 3rd and 4th fingers, Plantar surface bit toe, Earlobe
● Method of choice: NewBorn Screening
CAPILLARY
● Equipment used: Feather lancet
● Depth: <2mm for children, <3mm for adult
CAPILLARY
● DO NOT MILK THE SITE!! —-> _______________
Perpendicular
● Artery and Vein = __ layers
● Capillary = __ layer (thinner)
● Cherry red - Hgb __
● Artery and Vein = 3 layers
● Capillary = 1 layer (thinner)
● Cherry red - Hgb C
● Chocolate brown - _______
● Mauve - _________________
● Tomato red - Red cell suspension
● Chocolate brown- Methemoglobin
● Mauve - Sulfhemoglobin
● Tomato red - Red cell suspension
Improve the performance of a process by identifying and eliminating causes of defects and errors resulting in eliminating variation in the process
LEAN SIX SIGMA
Identify, measure, and eliminate the large gaps of inefficiency in a process
LEAN SIX SIGMA
● _____ – focus on reduction of waste
○ Customer value
○ Waste elimination
○ Speed
○ Flow
○ Resources
Lean
● __________ – Focus on reduction of error
○ Customer value
○ Defect,
○ Reduction
○ Reducing variation
○ Repeatability
○ Consistency
Six Sigma
___σ – highest value; ___σ – lowest
6σ – highest value; 3σ – lowest
In the highest level of westgard sigma control, the only error that can be committed is __________. Which means systematic error has been completely disregarded.
random error
● Refers to the overall process used to ensure that laboratory results meet the requirements for health care services to patients.
QUALITY MANAGEMENT
Focus:
■ Broader Monitoring
■ Turn-around Time
■ Patient preparation
Quality Assessment
is a major procedure for monitoring the analytical performance of laboratory testing processes.
Statistical QC
- Refers to procedures for monitoring work processes,
detecting problems and making corrections prior to the delivery of products and services.
Quality Control
Refers to the broader monitoring of other dimensions or other characteristics of quality such as turnaround time, patient preparation, specimen acquisition and result reporting that are monitored through broad QA activities.
Quality Assessment
Aimed at determining the root causes or sources of the problems being identified by QC and QA.
Quality Improvement
Represent the objectives or requirements that must be achieved to satisfy the customers.
Quality Goal
Concerned with establishing and validating processes that meet customer needs.
Quality Planning
Is a confirmation that the
requirements for specifically intended use or specific applications were met through
OBJECTIVE EVIDENCE (see forms like rubrics for scoring).
VALIDATION
It confirms that the level
of measurement is sufficient, the
measurement procedures are correct and the calibration was
done properly.
VALIDATION
It confirms that the measurement method/measuring system is
fully functional in a specific laboratory.
VERIFICATION
Is a confirmation that the analytical characteristics data
provided by the manufacturer
VERIFICATION
A laboratory or reference institution were achieved through
OBJECTIVE EVIDENCE in the
given laboratory with the use of a specific measuring system
VERIFICATION
Used to verify acceptability of new methods prior to reporting patient results and procurement of the machine
METHOD EVALUATION
Mnemonics for Performance Indicators (PI)
● All CC analyzers should PASSLR:
○ Precise
○ Accurate
○ Sensitive
○ Specific
○ Linearity
○ Ref. range
Validation may be accomplished by thoroughly testing reference materials or by comparison of results tests performed by alternative methods
○ PASS LR should be included
TECHNICAL VALIDATION
Should be performed before a test procedure is placed into routine use
TECHNICAL VALIDATION
● Performance indicator:
○ Sensitivity
○ Specificity
ANALYTICAL VALIDATION
Ability to accurately and reliably measure the analyte of interest in the clinical laboratory and in specimens representative of the population of interest
ANALYTICAL VALIDATION
Ability to diagnose or predict risk for a particular health condition, measured by clinical/diagnostic sensitivity and clinical/diagnostic specificity and predictive values
CLINICAL VALIDATION
○ Positive predictive value, and;
○ Negative predictive value
CLINICAL VALIDATION
Results of analytical measurement will definitely influence health, quality of life, and even the patient’s life (for patient safety)
REASONS FOR VALIDATION
● It is our professional duty to carry out measurement of sufficient QUALITY (comply with accrediting bodies)
● Accreditation (official confirmation of laboratory’s
competence) requires the use of properly validated and verified measurements
REASONS FOR VALIDATION
the amount of error that can be
tolerated without invalidating the medical usefulness of the result
Allowable Error
A method performed to determine is able to accurately
measure an analyte
PERFORMANCE STANDARD
