POCT (Challenges in laboratory medicine)

Point of Care Testing
(Challenge in Laboratory Medicine)
Dr.NashwaElsayedClinical Pathologist, CPHQ , CPOCT (AACC)
Laboratory & Blood Bank Quality Manager
Hospital Accreditations Manager
KFH-Medina, SA

Worldwide,
One of The Fastest Growing Aspects of Clinical
Laboratory Medicine is POCT.
It Is Growing At Higher Rate Than Conventional
Laboratory Testing
❖ Increasing at Least 10-12% Per Year Overall. Up to 30% Per Year in
some Testing areas.
❖ In Contrast, Central Laboratory Testing has Grown about 6-7%
Annually.
Dr. Nashwa Elsayed
POCT(Challenge inLaboratoryMedicine)

POCT ??
Point Of Care Testing
Tests Performed Outside the Clinical
Laboratories, Designed to be Used Near
the Patient & Do not Require Permanent
Dedicated Space.
(College of American Pathologist)
Dr. Nashwa Elsayed

Who Performs The POC Tests ?
➢Nurses
➢Physicians
➢Medics
➢Technicians (Outside Laboratories)
Dr. Nashwa Elsayed

Advantages of POCT
▪ Rapid & Simple Test.
▪ Small Sample Volume.
▪ Unprocessed Specimen.
▪ Built-in Quality Control.
▪ Portable Devices.
▪ Low cost.
Dr. Nashwa Elsayed

POCT
Regulatory & Accreditation
Requirements
Dr. Nashwa Elsayed

✓ CBAHI
✓ JCI
✓ CAP
✓ CLIA
✓ ISO
Dr. Nashwa Elsayed
Regulatory & Accreditation Bodies

POCT Standard (LB.28)
LB.28 The laboratory develops a comprehensive system for Point-of
Care-Testing (POCT).
LB.28.1 The laboratory implements policies & procedures to address the following:
LB.28.1.1 Clear definition of POCT.
LB.28.1.2 Assignment of the responsibility of managing the POCT to the laboratory.
LB.28.1.3 Guidelines describing the process of acquiring POCT devices/methods.
LB.28.1.4 Training and competency testing requirements.
LB.28.1.5 Maintenance, quality control, and quality management of the POCT
devices/methods.
LB.28.2 The laboratory assigned a qualified individual as POCT coordinator.
Dr. Nashwa Elsayed

POCT Standards (AOP.5.1.1)
AOP.5.1.1 A Qualified Individual is Responsible for the Oversight &
Supervision of the Point-of-Care Testing Program. 𝖯
Measurable Elements of AOP.5.1.1
1. The person responsible for managing the laboratory services, or a designee, provides
oversight and supervision of the POCT program.
2. Staff performing point-of-care testing have the required qualifications and training and are
competent to perform POCT.
3. The POCT program includes a defined process for reporting abnormal test results,
including reporting of critical results.
4. The POCT program includes quality control performance, documentation, and evaluation.
5. The POCT program is monitored and evaluated and included in quality improvement
activities.
Dr. Nashwa Elsayed

POCT Checklist
• POCT has a Separate Checklist that includes:
1. Oversight and Governance,
2. Document Control,
3. Process Improvement,
4. Equipment,
5. Purchasing and Inventory,
6. Quality Assurance,
7. Personnel Policies and Training,
8. Pre-Analytical Processes and Analytical Processes.
9. Latest Addition of IQCP wherever Applicable.
Dr. Nashwa Elsayed

CLIA Certifications
• Certificate of Waiver.
• Certificate for Provider Performed Microscopy (PPM)
Procedures.
• Certificate of Registration and Certificate of Compliance.
• Certificate of Accreditation
Dr. Nashwa Elsayed

ISO 22870 Certificate
• ISO 15189 Applies to Medical Laboratories.
• ISO 22870 Applies Specifically to POCT.
Dr. Nashwa Elsayed

POCT Successful Program
• Implementation of a Successful POC test Can be
a Complex Process that Requires Special Skills.
• POCCs should have a Basic Understanding of
the Related Sections in the Main Laboratory
from which the Method or analyzer be Derived.
Dr. Nashwa Elsayed

Challenges Associated
with POCT
Dr. Nashwa Elsayed

Management Responsibility
This Is A Great Challenge
For Laboratories
As
The Testing Performed Out of their Hands,
But still the Lab is Accountable for Ensuring Compliance
with Laboratory Accreditation Standards.
Dr. Nashwa Elsayed

POCT is performed by Clinical Staff rather
than Laboratory Trained Individuals which
can lead to errors resulting from a lack of
understanding of the importance of Quality
Control And Quality Assurance Practices.
Dr. Nashwa Elsayed

Challenges Associated with POCT
• Documentation of POCT orders,
• Charting of POCT results
• Training and certification of individuals performing
POCT.
• Pre-analytical factors Associated Errors.
• Quality Assurance.
Dr. Nashwa Elsayed

Challenges in Critical Care
POC Blood Gas Testing
Dr. Nashwa Elsayed

• “Blood gas and pH analysis has more immediacy and potential
impact on patient care than any other laboratory determination.”
• ”In blood gas and pH analysis an incorrect result can often be
worse for the patient than no result at all”
• ”Arterial blood is one of the most sensitive of the specimens sent
to the clinical laboratory for analysis”
“National Committee for Clinical Laboratory Standards
(NCCLS)”
Dr. Nashwa Elsayed
Pre-Analytical Error

Dr. Nashwa Elsayed
• Pre Analytical Errors Represents 68% Of Total
Errors In Laboratory Medicine.
• 75% Of Error In Blood Gases Analysis Occur
From Pre Analytical Factors.
68%13%
19%
Pre-analytical
Analytical
Post analytical

Dr. Nashwa Elsayed
Impact on the patient?
• Inappropriate or Delayed Treatment
• Increased Length of Hospital Stay
• Increased Morbidity & Mortality
• Pain – sticks hurt!

Dr. Nashwa Elsayed
• Awareness is Important.
Reduced Error Improved Care
Better Patient
Outcome

Dr. Nashwa Elsayed
Pre-Analytical Phase
1
• Ordering
2
• Identification
3
• Collection
4
• Sample handling
5
• Transportation

Dr. Nashwa Elsayed
Ordering
Hard
Copy
Electronic
Copy

Dr. Nashwa Elsayed
Ordering
1. Name of Patient
2. MRN
3. Age
4. Sex
5. Operator ID
6. Date & time of sample Collection

Dr. Nashwa Elsayed
Identification

Dr. Nashwa Elsayed
Identification
1. Label Immediately After Sampling:
2. Avoid Mix-up of Samples
3. Avoid Missing Samples
4. Avoid Poor Data

Dr. Nashwa Elsayed
Collection
The ideal collection device for arterial blood
sampling is:
✓ Plastic Syringe
✓ Self-filling Disposable
✓ a 1-, 3-, or 5-mL
✓ Prefilled With Appropriate Type Of Lyophilized
Lithium Heparin.

Dr. Nashwa Elsayed
Other Collection Devices
1. Syringes, not dedicated for blood gas analysis:
(insulin syringe, etc). Not to be used. High risk of
hemolysis and gas exchange.
2. Vacutainer to be avoided, due to the negative
pressure on pCO2 and pO2.

Dr. Nashwa Elsayed
Collection by Capillary Tubes
When circumstances do not allow true arterial
sampling, capillary blood sampling may be selected as
an alternative method

Dr. Nashwa Elsayed
Collection by Capillary Tubes
Correlation
pH and pCO2,
Good Correlation is demonstrated between a capillary (arterialized)
blood sample and the equivalent arterial one
pO2
the Correlation Is Poor (due to the variable percent of venous
component in the sample)
K
Significant Differences are caused in the process of “arterialization”
or hemolysis.

Brachial Artery
at the Elbow
Femoral Artery at the
Inguinal Ligament
Capillary at the Heel
Capillary at the Ear Lobe
Radial Artery
at the Wrist
Mixed Venous Blood
At the pulmonary artery
Collected with catheter
Capillary at the Fingers
Puncture Sites
Dr. Nashwa Elsayed

Dr. Nashwa Elsayed
Sample Handling
➢ Whole blood samples must be mixed thoroughly
(particularly for Hb & Hct accuracy).
➢ Recommendation:
✓ 30 second minimum (or longer)
✓ Mix immediately & remix prior to analysis
✓ Mix in two planes (rock & roll)
✓ Be gentle (prevent hemolysis, very important for K)

Dr. Nashwa Elsayed
Sample Handling
➢ Expel Air Immediately & Completely
➢ Measure < 30 Minutes - Room Temperature*
➢ Measure 30-60 Minutes - Ice/Water Slurry*
*CLSI document H11-A4, Vol 24 No 28. Procedures for the Collection of Arterial Blood Specimens.

Dr. Nashwa Elsayed
Iced Vs Non-iced
➢ Ice slurry (metabolic inhibition)
• Helps preserve pH, pCO2, pO2, glucose & lactate
• pO2 might increase in plastic syringes
• May increase K+, decrease Na+
➢ Non-iced
• Must analyze quickly
• No change in K+
•  Glucose 0.5 mmol/L Hr
•  Lactate 0.5 mmol/L/Hr

Dr. Nashwa Elsayed
Handling of Capillary Sample
Puncture Site should be:
➢ Pre-warmed up to (42 C), increases flow up to 7X
➢ Free-flowing sample
“milking” introduces venous blood and interstitial fluid
➢ Completely filled, air free tubes, with sealed ends
➢ Should be analyzed within 10 minutes, with plastic caps.

Dr. Nashwa Elsayed
1. Remove the first blood drop before sampling
2. Cap and roll tube immediately
3. Using the small magnet, move the metallic
flea in the capillary at least 5 times forward
and back before analyzing the sample. This
make the blood homogeneous and reduce the
risk of micro clottings

Dr. Nashwa Elsayed
• Move the metal wire flea from end to end
• Analyze as soon as possible (max delay 10 mins)

Dr. Nashwa Elsayed
Sample Transport
Effect of Time on Blood Gas Sample
↓ pO2 Oxygen will still be consumed
↑ pCO2 Carbon dioxide will still be produced
↓ pH Primarily due to the change in pCO2 and glycolysis
↑ cCa2+ Change in pH will influence the binding of Ca2+ to protein
↓ cGlu since glucose will be metabolized
↑ cLac due to glycolysis
Continued cellular metabolism in sample

Dr. Nashwa Elsayed
Pneumatic Tube Transport (PT)
➢ pH and pCO2 not affected by PT, regardless of use of
Pressure sealed/non-sealed containers
➢ pO2 significantly altered in non-sealed containers.
➢ pO2 No Alteration if sent in pressure sealed containers.
POC Blood Gas Is A Huge
Advantage In This Respect

Dr. Nashwa Elsayed
Venous Admixture
➢ The addition of 10% of venous blood to an arterial
sample can produce > 25% drop in Po2
➢ Increased Probability On Femoral Artery Punctures
Suspect Venous Contamination If Condition &
ABG Results Do Not Correspond With Patient
Clinical Picture

Dr. Nashwa Elsayed
Hemolysis
➢ Hemolysis causes the release of intracellular
components from destroyed erythrocytes into
extracellular fluid.

Dr. Nashwa Elsayed
Hemolysis
The following actions might cause hemolysis:
➢Vigorous mixing
➢Blood collection: pressure increase through a narrow
diameter syringe or when path is blocked by clots
➢Squeezing the skin during capillary blood sampling
➢Storage directly in ice
➢Transport on pneumatic tube system

Dr. Nashwa Elsayed
Quality of ABG Analyzer
Testing performed by Non-
laboratory Professionals
❖Not familiar with testing process
❖No time allocated for testing
❖Primary responsibility is patient care
❖No time for quality control
❖No understanding of QC
❖Not familiar with QC interpretation
Quality is a Concern at POCT!

Dr. Nashwa Elsayed
The technology for ABG measurements is based on the
use of electrodes. Their performance is slightly changing
during its life,
To Verify That The Response Of The System Is Within
Acceptable Range A Calibration Have To Be
Performed.

Dr. Nashwa Elsayed
So, Every time a new blood sample is introduced on the
analyzer;
The Risk To Report Not Reliable Result Increases, For This
Sample And For The Subsequent, Specially If There Is A
Poor Pre-analytic Phase.

Dr. Nashwa Elsayed
The solution about Quality
Analyzing on the BG analyzer a solution with known concentration
and comparing the result with the values given by the instrument is
the common way to find errors in the system.
If the QC is outside of the expected range, then the instrument alerts
the operator to take the corrective action, in the most advanced
analyzer the parameter that failed is automatically disabled.
More often the QC’s are analyzed “less” probability to report
wrong results.

Dr. Nashwa Elsayed
Types of Blood Gas QCTraditionalExternalQualityControl
• Introduced
by the
operator
• factor of
risk
AutoQC
•The QC
solutions or
ampoules are on
board.
•The system is
controlled at a
determinated
frequency
•(tipically every
8/12 or 24 hours)
AutomaticRealTime(iQM©)
•Automatic
detection,
correction and
report.
•The system is
controlled after
every sample &
determinated
fixed frequency
30 seconds, 30
minutes,4 hours,
24 hours, etc.

• Failures detected
• Automatic QC control
• Auto QC requires active
operator supervision
• Auto QC requires instrument
corrective actions
• Temporary failures might not
be detected:
• Air contamination
• Electrodes drift
• Clots and micro clots
• Interferences
Blood Gas QC

Dr. Nashwa Elsayed
iQM:
Intelligent Quality Management
What does iQM do?
It runs Automatically Real Time Quality Control for all the system:
✓ Automatically Detects Issues in the system
✓ Automatically Performs Corrective Actions
✓ Automatically Documents The Failure & Corrective Actions taken

Dr. Nashwa Elsayed
How iQM Enhances
Patient Care Safety?
Start of Shift
(8-hour QC)
Start of Shift
(8-hour QC)
Measurement problem occurs
Measurement problem detectedQuestionable test results
Reliable test resultsTraditional or
Automatic QC
Ongoing, Continuous QC testing
Measurement problem detected
Reliable test results
Measurement problem occurs

A New QC Paradigm
Intelligent Quality Management (iQM) is used as the quality control and
assessment system for the GEM Premier 4000 system. iQM is an active
quality process control program designed to provide continuous
monitoring of the analytical process with real-time, automatic error
detection, automatic correction of the system and automatic
documentation of all corrective actions, replacing the use of traditional
external quality controls.
Dr. Nashwa Elsayed

What does iQM for POCT operators?
Real Time Manufacturer guaranteed
quality without: “?”
Dr. Nashwa Elsayed

Operator Notification
Dr. Nashwa Elsayed

iQM Detecting Interference
Dr. Nashwa Elsayed

Automatic Documentation
57
Delta Chart
Corrective Actions
Report
Dr. Nashwa Elsayed

iQM Validation Dr. Westgard
Dr. Nashwa Elsayed

POCT is a Lean Process
Testing on-site Requires Fewer Steps than
Transporting a Specimen to a Core Laboratory
that Improve Patient Outcome or Workflow
by having Immediately Available Results.
Point-of-Care-Testing can have
a Positive Impact on Operational Efficiency
and Patient Care.
Dr. Nashwa Elsayed

Thank You
Dr. Nashwa Elsayed

POCT (Challenges in laboratory medicine)

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