SOP for Omni-S And Cobas b221 Gas Analysers

SOP for Omni-S And Cobas b221 Gas Analysers
RUH Bath NHS Foundation Trust – Pathology Department
STANDARD OPERATING PROCEDURE
SOP/POCT/15/16
Title: OMNI-S+COBAS b221 Point of Care
Analysers
Effective date: 28/07/15
COPY
Summary of Significant Changes at this Revision
Section 8.1. Daily maintenance - replacing of fluid packs – remove rubber seal before inserting new
pack.
Section 8.2. Weekly Maintenance - cleaning T+D and fill port – include Roche procedure including
automatic initialisation.
Section 8.3. Monthly Maintenance – changing the waste separator – first de-activate the analyser by
opening the reagent compartment door.
Section 8.5 Six Monthly Maintenance – changing Peristaltic Pump Tubes – include Roche procedure
including automatic initialisation.
Purpose and Scope
This SOP describes the principles and
procedures involved in the analysis of:
Blood gases – pH, pCO2, pO2
Bicarbonate – cHCO3Electrolytes – Na+, K+, ionised Ca++, ClHb derivatives – COHb
(Carboxyhaemoglobin) etc.
Bilirubin (neonatal)
Glucose
Lactate
Using Omni –S and Cobas b221 POC
analysers.
Items Required
Omni – S analyser.
Cobas b221 analyser.
Analyser reagents and consumables as
supplied by Roche for the running of the POC
analysers.
Heparinised blood gas collection syringes.
Heparinised blood gas collection capillary
tubes.
Clot catchers.
Ampoule adapters.
IQC materials.
Definitions and Abbreviations
POC – Point of Care
Grade / Qualifications Required
QC – Quality Control
IQC – Internal Quality Control
EQA – External Quality Assurance
QA – Quality Assurance
WEQAS – Welsh External Quality Assurance
AQC – Auto Quality Control
ABG – Arterial Blood Gas
CPAP – Continuous positive airways
pressure
MSS – Metabolite Sensitive Sensors
ISE – Ion Selective Electrodes
TB – Tuberculosis Bacilli
T/D – Turn and Dock
Biomedical Scientist
Doctor
Nurse
Emergency Department Assistant (EDA)
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RUH Bath NHS Foundation Trust – Pathology Department
STANDARD OPERATING PROCEDURE
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Title: OMNI-S+COBAS b221 Point of Care
Analysers
Effective date: 28/07/15
INDEX
1.
2.
3.
4.
5.
6.
7.
8.
INTRODUCTION ........................................................................................................................... 3
PROCEDURAL SUMMARY ......................................................................................................... 3
CLINICAL APPLICATION ........................................................................................................... 3
METHOD PRINCIPLES ................................................................................................................. 6
REAGENT INFORMATION .......................................................................................................... 6
CALIBRATION .............................................................................................................................. 8
QUALITY CONTROL .................................................................................................................... 9
MAINTENANCE .......................................................................................................................... 11
8.1 Daily Maintenance ..................................................................................................................... 11
8.2 Weekly Maintenance .................................................................................................................. 13
8.3 Monthly Maintenance ................................................................................................................ 16
8.4 Three-Monthly maintenance ...................................................................................................... 18
8.5 Six - Monthly Maintenance ........................................................................................................ 18
8.6 As Required Maintenance .......................................................................................................... 19
9. SAMPLE REQUIREMENTS ........................................................................................................ 20
10.
PATIENT TESTING ................................................................................................................. 22
10.1 Capillary Measurement ............................................................................................................ 22
10.2 Syringe Measurement ............................................................................................................... 23
10.3 Small Syringe Samples (<100μL)............................................................................................. 23
10.4 Bicarbonate (cHCO3-st)(Lab only) .......................................................................................... 23
10.5 Pleural Fluid pH syringe sample (Lab only) ........................................................................... 23
11. REPORTING AND INTERPRETATION .................................................................................... 25
11.1 Interferences ......................................................................................................................... 25
11.2 Analytical ranges .................................................................................................................. 25
11.3 Reference ranges .................................................................................................................. 26
11.4 Results Entry ......................................................................................................................... 26
11.5 Limitations ............................................................................................................................ 26
12. REFERENCES ............................................................................................................................... 27
APPENDIX - NEW LOT NUMBER OF IQC ............................................................................................. 28
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RUH Bath NHS Foundation Trust – Pathology Department
STANDARD OPERATING PROCEDURE
SOP/POCT/15/16
Title: OMNI-S+COBAS b221 Point of Care
Analysers
1.
Effective date: 28/07/15
INTRODUCTION
The Roche OMNI-S/Cobas b221 POC analysers are used for the measurement of blood gases,
electrolytes, haemoglobin derivatives, neonatal bilirubin, glucose and lactate in whole blood,
serum, plasma, dialysate (electrolytes only), pleural fluid (pH only) and QC material. In addition
to this, there are a number of calculated parameters available e.g. bicarbonate (cHCO3-).
2.
PROCEDURAL SUMMARY
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Blood gas samples sent to the lab should be received on ice, within 1 hour of sampling
via the portering service. Samples should NOT be analysed if received via the
pneumatic transfer system.
Lab samples - request the sample in Ultra using the test code ‘GAS’
On the OMNI-S/Cobas b221 screen, check that the status window displays ‘Ready’ and
the parameter buttons that you require are green.
Mix the sample well and expel the first few drops to eliminate clots.
Attach a clot catcher
Press the syringe firmly to the fill port.
Inject the sample slowly.
Remove the syringe when prompted to do so by the analyser.
NB. Refer to later in the SOP for further details for analysing capillary/small syringe
samples.
While the sample is being analysed, enter the mandatory information (highlighted red)
using the touch screen.
When measurement is complete, remove the printout from the analyser.
Ward samples – transcribe the results into the patient’s notes along with the date +time
performed, the location of the analyser used + signature of operator
Lab samples - enter the results in Ultra using the ‘VRES’ program
Lab samples - Release the results for authorisation from ‘VRES’.
Lab samples - Check the ‘Telephone Queue’ for any results, which need to be
telephoned.
3. CLINICAL APPLICATION
Blood Gases
The measurement of ABGs provides valuable information in assessing and managing a
patient’s respiratory (ventilation) and metabolic (renal) acid-base and electrolyte homeostasis.
It is also used to assess the adequacy of oxygenation. ABGs are used to monitor patients on
ventilators, monitor clinically ill non-ventilated patients, establish pre-operative baseline
parameters, and regulate electrolyte therapy. Repeat blood gases enables the assessment of
oxygen pressure to guide therapy of patients on ventilators or continuous positive airways
pressure (CPAP) machines so that the treatment can be adapted to preserve the patient’s
normal physiological balance.
The measurement of pH and pCO2 (and subsequent calculation of HCO3-) enables the
assessment of acid-base balance. This provides the means of identifying many diseases,
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Title: OMNI-S+COBAS b221 Point of Care
Analysers
Effective date: 28/07/15
especially when combined with determination of electrolytes. For further information, please
refer to references 1 and 2.
Electrolytes
Sodium and Potassium
The electrolytes Na+ and K+ are measured as part of a routine laboratory evaluation of all
patients. They are used to evaluate and monitor fluid and electrolyte balance and response to
therapy. Sodium is the principal extracellular cation and determinant of extracellular fluid
osmolality and volume, and its concentration is the result of a balance between dietary sodium
intake and renal excretion. Potassium is the major intracellular cation, and is important in
maintaining membrane electrical potential, especially in neuromuscular tissue (most notably,
heart muscle). Potassium also contributes to the metabolic portion of acid-base balance. It is a
very important test, but especially to those who take diuretics or heart medications.
Chloride
Chloride is the most important anion in bodily fluids and is located mainly in the extracellular
area. Chloride is glomerularly filtered in the kidneys and is tubularly reabsorbed by passively
following sodium. Chloride works with sodium to regulate the acid/base status and may be
exchanged for bicarbonates during acid/base disturbances. Hypochloremic alkalosis may occur
during extended periods of vomiting, in which chloride is lost in the gastric juices.
Ionised Calcium
Calcium in blood is distributed as free calcium ions (50%), bound to protein (mostly albumin,
40%), and 10% bound to anions such as bicarbonate, citrate, phosphate and lactate. However,
only ionised calcium can be used by the body in such vital processes as muscular contraction,
cardiac function, and transmission of nerve impulses and blood clotting. Patients with renal
disease caused by glomerular failure often have altered concentrations of calcium, phosphate,
albumin, magnesium and pH. Since these conditions tend to change the ionised calcium
independently of total calcium, ionised calcium is the preferred method of accurately monitoring
calcium in renal disease. (See reference 3)
Haemoglobin Derivatives (Haemoximetry)
Haemoximetry is used for:
i)
Investigation of the efficiency of haemoglobin oxygenation by the lungs (Hb
saturation)
ii)
Measurement of non-oxygen-carrying blood pigments (Carboxyhaemoglobin,
Methaemoglobin and Sulphaemoglobin)
iii)
Investigation of patients with likely abnormalities of oxygen carriage and release,
e.g. acidosis, alkalosis, hypoxaemia.
Carboxyhaemoglobin is measured in the investigation of possible carbon monoxide exposure
and poisoning. Methaemoglobin and Sulphaemoglobin are measured in the investigation of
unexplained central cyanosis and possible oxidant drug haemolysis (e.g. sulphonamides,
aniline dyes, nitrates and nitrites). Increased levels of Methaemoglobin are seen in patients
with HbM haemoglobinopathy or Methaemoglobin-reductase deficiency and flowing oxidant
drug exposure. Sulphaemoglobin may occur with exposure to certain drugs, especially
sulphonamides.
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Title: OMNI-S+COBAS b221 Point of Care
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Effective date: 28/07/15
Bilirubin (neonatal)
Bilirubin is formed in the reticuloendothelial system during the degradation of erythrocytes. The
haem portion from haemoglobin and from other haem-containing proteins is removed,
metabolised to bilirubin, and transported as a tightly bound complex with serum albumin to the
liver. In the liver, bilirubin is conjugated with glucuronic acid for solubilisation and subsequent
transport through the bile duct and elimination via the digestive tract.
The concentration of bilirubin in the plasma of an individual is determined by the balance
between production and clearance. Any disease process which disrupts this balance will lead
to an increase in plasma bilirubin.
In the newborn, the massive red cell destruction occurring in haemolytic disease of the
newborn, coupled with the immature hepatic handling of bilirubin, can produce elevations of
unconjugated bilirubin of 400 – 500 μmol/L or greater. Such elevations are associated with the
risk of developing kernicterus (deposition in the brain with cerebral damage) and levels may be
reduced by exchange transfusion.
Also, in premature infants, the poorly developed conjugating mechanism may result in socalled ‘physiological’ jaundice with markedly raised levels of unconjugated bilirubin,
necessitating ultraviolet light treatment or exchange transfusion.
Some drugs can further influence the course and severity of neonatal unconjugated
hyperbilirubinaemia caused by the immature hepatic handling of bilirubin by:
a) displacing bilirubin from plasma albumin,
b) inhibiting the glucuronyl transferase system
c) causing haemolysis.
Another reason for measuring bilirubin in neonates is for the diagnosis of Crigler-Najjar
syndrome. This harmful congenital disease presents in the first few days of life as jaundice, due
to a rise in unconjugated bilirubin levels that may often be high enough to cause kernicterus,
and is caused by a deficiency of glucuronyl transferase. In infants who survive, the level of
bilirubin tends to stabilise, suggesting the existence of alternative pathways of bilirubin
excretion.
Rarely, a baby may be born with a congenital condition called biliary atresia, in which the bile
ducts do not drain. It usually presents within the first few weeks of life, with jaundice that does
not improve with time. This form of hyperbilirubinaemia is largely due to conjugated bilirubin
and may be corrected by surgery. Delay in diagnosis of the condition can lead to irreversible
liver damage.
Glucose
Glucose measurements are used in the diagnosis and treatment of carbohydrate metabolism
disorders including diabetes mellitus and hypoglycaemia.
Glucose is the major carbohydrate present in the peripheral blood. Oxidation of glucose is the
major source of cellular energy in the body. Glucose derived from dietary sources is converted
to glycogen for storage in the liver or to fatty acids for storage in adipose tissue. The
concentration of glucose in blood is controlled within narrow limits by many hormones, the most
important of which is insulin produced by the pancreas. The most frequent cause of
hyperglycaemia is diabetes mellitus, resulting from a deficiency in insulin secretion or action. A
number of secondary factors also contribute to elevated blood glucose levels. These include
pancreatitis, thyroid dysfunction, renal failure, and liver disease.
Hypoglycaemia is less frequently observed. A variety of conditions may cause low blood
glucose levels such as insulinoma, hypopituitarism, or insulin-induced hypoglycaemia.
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STANDARD OPERATING PROCEDURE
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Title: OMNI-S+COBAS b221 Point of Care
Analysers
Effective date: 28/07/15
Lactate
Lactate acts as an early warning signal for hypoxic states in human tissues. Anaerobic
glycolysis markedly increases blood lactate and causes some increase in pyruvate levels,
especially with prolonged exercise. The common cause for increased blood lactate and
pyruvate is anoxia resulting from such conditions as shock, pneumonia and congestive heart
failure. Lactic acidosis may also occur in renal failure and leukemia. Thiamine deficiency and
diabetic ketoacidosis are associated with increased levels of lactate and pyruvate.
Lactate measurements that evaluate the acid-base status are used in the diagnosis and
treatment of lactic acidosis.
4. METHOD PRINCIPLES
The blood gases and electrolyte concentrations of the sample are all measured by electrodes.
pH, Na+, K+, Ca++ and Cl-electrodes are potentiometric electrodes. Special glasses are used
as the sensitive element for pH and Na+. The potassium and calcium membranes contain
special neutral carriers. A special ion exchanger is used for Cl- membranes. Calculations of
these variables also requires the use of a reference electrode – a permanently contacted
chloride electrode.
pCO2 electrode is a Severinghouse model - Potentiometric measurement of the pH change in
the electrode caused by CO2.
pO2 electrode is a Clark electrode - Measurement of current generated by the reduction of
oxygen.
Glucose and Lactate are measured in the MSS measuring chamber, by the MSS cartridge,
which is a multi-parameter sensor.
Glucose is oxidised by glucose oxidase and atmospheric oxygen to form gluconolactone.
Lactate is oxidised by lactate oxidase to form pyruvate. The H2O2 generated from these
reactions is determined amperometrically using manganese dioxide/carbon electrodes at
350mV.
Haematocrit - measurementof the sample’s conductivity in the ISE measuring chamber.
Haemoglobin Derivatives and Bilirubin (neonatal) are measured by co-oximetry; they are
determined spectrophotometrically based on Beer-Lambert’s law. Following haemolysis,
absorbency of the sample is measured at various wavelengths and the resulting equation is
solved to determine the concentration of the constituent haemoglobin derivatives. Light emitted
by a halogen lamp is partially absorbed by the sample, partially transmitted. The transmitted
light is directed onto the polychromator, where it is diffracted and imaged onto the surface of a
photosensitive device. The resulting electrical signal is used to determine the absorption, and
thus the concentration of the haemoglobin derivatives.
5. REAGENT INFORMATION
Reagent location
A supply of reagent packs is kept alongside each analyser as appropriate.
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STANDARD OPERATING PROCEDURE
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Title: OMNI-S+COBAS b221 Point of Care
Analysers
Effective date: 28/07/15
These are:
S1 Rinse Solution (03260917184) – Wash water
S2 Fluid Pack (03260925184) – Calibration and reference solutions for the Blood Gas and ISE
modules, Na conditioning solution, O2 zero point solution, cleaning solution.
S3 Fluid Pack (03260933184) – 4 Calibration solutions for glucose and lactate, MSS standby
solution, MSS reference solution.
Deproteiniser (03110435180) – A stronger cleaning solution for the sample path when
necessary.
tHb Calibrator (03110923035) – A dye solution for the calibration of the CO-OX module.
Stock solutions
Lab/NICU – further supplies of reagents are stored in the bulk store in the pathology
department.
A+E/MAU/ITU – further supplies of reagents are stored in the appropriate departmental store
rooms.
Stock Quality Control Material is stored in the pathology department cold store.
Only one full mat of each level of QC should be kept on the analyser at a time, because the
OMNI-S/Cobas b221 QC drawers are NOT temperature controlled.
Please complete the stock control sheet for the appropriate reagent when a box is finished, or a
new box is started.
Reagent preparation
All reagents are supplied ready for use.
Reagent Storage & Stability
All the reagents have a storage temperature requirement of 15 - 30°C with the exception of the
S3 reagent pack, which must be stored below 25°C.
The Quality Control Material is stored at 2 - 8°C
All the reagents are stable on the shelf until their expiration date, which is printed on the
containers. They should not be used beyond this date.
Once on board the analyser, the reagent packs will expire after 42 days, and cannot be used
after this time.
COSHH
Deproteiniser : An aqueous solution of Sodium Hypochlorite (NaOCl) containing ≤ 2% active
chlorine. Due to the basic and oxidising character of the reagent local irritations may occur after
contact with eyes, skin or mucous membranes.
Deproteiniser is used by lab staff only and any waste solution should be flushed away down the
laboratory sluice (in line with POL/HS/1). The plastic bottle should be rinsed and disposed of in
the lab plastic recycling.
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STANDARD OPERATING PROCEDURE
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Title: OMNI-S+COBAS b221 Point of Care
Analysers
Effective date: 28/07/15
All other reagents and QC Materials used on the OMNI-S/Cobas b221 analysers contain no
substances hazardous to health in reportable quantities. The tHb Calibrator/IQC glass
ampoules should be disposed of in a sharps container after use. All non-hazardous reagent
containers can be emptied and put in landfill or plastic recycling waste.
Refer to the Safety Data Sheets in the Roche blood gas analyser Reference Manual for further
information.
6. CALIBRATION
Blood Gas and ISE Calibration
The OMNI-S/Cobas b221 analysers use two aqueous base solutions for the simultaneous
calibration of the pCO2, pH, Na+, K+, iCa++ and Cl- sensors. This calibration is based on the
generation of calibration solutions as part of the calibration process by mixing two stable
solutions, calibration solution A and calibration solution B (in the S2 fluid pack).
The pO2-value of room air, determined by the continuously monitored barometric pressure and
a solution with a pO2 of zero (also in the S2 Fluid pack), are used for the calibration of the pO2
sensor.
Glucose and Lactate Calibration (Cobas b221 only)
Calibration of the MSS parameters takes place using 4 solutions, whose weighing
concentration forms the basis for determining the measured values. All MSS calibrations are
referenced to a reference measurement using a standby solution. This reference measurement
is carried out after the calibration solution has been measured.
Co-Ox Calibration
A charge-coupled device is used to collect the spectral information at several wavelengths in
the visible range. Once a day, during the system calibration, a complete wavelength calibration
is automatically performed using a built-in light source.
As part of the 3-monthly maintenance, and after any cuvette manipulation, an external tHbcalibrator is used for calibration of the tHb channel.
The following calibrations are automatically initiated and performed by the analyser:
CALIBRATIONS
TIME INTERVALS
SYSTEM
1 POINT
2 POINT
ELECTRODE EXCHANGE
EVERY 24H
EVERY 30 MINS
EVERY 12 HRS
AS REQUIRED
DURATION (mins)
without MSS
11
2
6
25
DURATION (mins)
with MSS
16
3
11
50
When an automatic calibration is imminent, the calibration window at the bottom of the screen
flashes red. If it is not interrupted within 20 seconds, the OMNI-S/Cobas b221 will start the
calibration.
N.B. Do not interrupt a calibration once it has started.
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Title: OMNI-S+COBAS b221 Point of Care
Analysers
Effective date: 28/07/15
Calibration for Ready
Failed Calibrations: Parameters that are grey with a red cross – can be corrected
by
•
•
•
Press: System > Calibration (from the Analyser Mode screen)
Press: Calibration for ‘Ready’ – automatically selects a calibration which will transfer
all selected parameters to the ‘Ready’ state.
Press: Start
Further user-activated calibrations can be initiated following troubleshooting investigations
by:
• Pressing: System > Calibration (from the Analyser Mode screen)
• Select the relevant calibration (eg PO2, 2P Cal)
• Press: Start
Storage & Stability
All the calibration solutions have a storage temperature requirement of 15 - 30°C.
All are stable until their expiration date, which is printed on the containers; and an on-board
expiration of 42 days. They should not be used beyond these dates.
COSHH
All the calibration solutions used on the OMNI-S/Cobas b221analysers contain no substances
hazardous to health in reportable quantities. Refer to Safety Data Sheets (Roche OMNI
S/Cobas b221 Reference Manual) for further information.
7. QUALITY CONTROL
IQC is used to ensure analytical precision on a daily basis. The IQC materials control all of the
measured parameters on all of the modules (electrolytes, gases, co-oximetry, bilirubin, glucose
and lactate.). Calculated parameters e.g. bicarbonate (HCO3-) and base excess (BE) are not
controlled by IQC as they are a factor of the measured parameters.
The following IQC materials are used:
Auto-trol Plus B Level 1 (Product No. 03321169001)
Auto-trol Plus B Level 2 (Product No. 03321177001)
Auto-trol Plus B Level 3 (Product No. 03321185001)
The OMNI-S/Cobas b221 analysers are set up to do automatic measurement of three QC
materials with known values or ranges of expected values - two are analysed on a daily basis,
which checks the precision and accuracy of the analyser. The QC results are acceptable if they
come within the 2 standard deviation ranges set up on the instrument.
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Effective date: 28/07/15
Locked Out QCs
N.B. Any QC results which violate this rule results in the affected parameter(s)
being locked out (see icon) until a successful QC measurement is accomplished
for the material/level combinations affected.
QC for Ready – This allows locked out QCs to be rerun automatically.
• Press QC Measurement
• Press QC for Ready
• The locked out QC(s) will be run automatically in turn by the analyser
QC ‘lock out’ status can be checked by pressing each locked out parameter icon.
This will show which QCs are locked out for that parameter – this can be printed.
Performing a Manual QC
QCs can be performed manually to determine if the QC failure is due to a problem with
AUTOQC sampling.
Having first determined which QC level/s are blocked (as above) remove an ampoule of the
relevant QC from the AQC drawer.
- With the analyser in ‘Analyser’ mode (syringe icon) press :
- QC measurement>
- Select level>
- Start Manual QC
- Present the ampoule to the fill port using an ampoule adapter and press ‘Aspirate Sample’
- Remove the sample from the fill port when prompted to do so by the analyser
- Enter your operator ID (lab analyser only)
- Repeat operation if necessary
The manually used QC ampoules must be registered on the analyser:
- From ‘Analyser’ mode (syringe icon), open the AQC drawer and press ‘details’ below the
appropriate mat
- ‘Remove’ the used ampoule from the analyser record by touching the number in the
relevant position, so that the icon turns grey
- Go back a page to save
The QC inventory should be checked as part of the weekly maintenance to ensure sufficient
QC material is on board.
Storage & Stability
All the Quality Control materials have a storage temperature requirement of 2 - 8°C.
If kept under these conditions, they are stable until their expiration date, which is printed on the
containers. They should not be used beyond this date.
COSHH
All the Quality Control materials used on the OMNI-S contain no substances hazardous to
health in reportable quantities. Refer to Safety Data Sheets (Roche OMNI S/Cobas b221
Reference Manual) for further information.
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Title: OMNI-S+COBAS b221 Point of Care
Analysers
Effective date: 28/07/15
External Quality Assurance (EQA)
The purpose of EQA is to assess the accuracy (bias) of results produced compared to target
values achieved by other method users nationally. Thus performance is monitored
retrospectively.
WEQAS samples are received and analysed for all analytes except Bilirubin, on a monthly
basis. Blood Gas and Co-Ox EQA samples are analysed on the lab analyser and are also sent
out by the lab to the following departments:
NICU, A+E, MAU, RESPIRATORY WARD/LAB, ITU and CARDIAC CENTRE.
An RUH lab QA scheme is used for monitoring Bilirubin in NICU and the lab.
Refer to SOP/POCT/39 – WEQAS Blood Gases and Co-Oximetry for full details and
instructions.
8. MAINTENANCE
Maintenance actions should be recorded on the maintenance schedule list using:
Quick Access > Maintenance > Do
- as well as on the Maintenance tick charts.
8.1 Daily Maintenance
1. Check fluid levels and replace reagent packs and/or waste container if necessary.
Press:
>Fill levels
This screen gives you a display of the current levels of fluid in the fluid packs along with lot
number and expiry date details and a date on which a change of bottle is to be expected.
Solutions will need to be changed depending on the rate of measurement and/or the onboard
stability. Exchange empty bottles, bottles whose usage date has expired, and full waste bottle.
If a fluid pack needs replacing:
From the main ‘Analyser mode’
screen
- Open the bottle compartment cover
- The bottle exchange image appears on the display.
- Open the docking mechanism and pull out the bottle/pack to be exchanged.
- N.B. Empty S1 bottles should be kept for use as a waste container – see later.
- Remove the rubber seal from the new pack.
- Insert the new bottle or pack in the corresponding position until it stops.
- The Roche OMNI-S/Cobas b221 recognises the correct bottle or pack and verifies
the expiration date. If the bottle has passed its expiration date, the screen displays a
warning.
- Close the docking mechanism.
- Close the bottle compartment cover. The solutions are automatically aspirated
upwards (detection in the flap) and the appropriate prime and calibration are
initiated as required.
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If the waste container needs replacing:
From the main ‘Analyser mode’
screen
- Open the bottle compartment cover.
- The bottle exchange image appears on the display
- Open the docking mechanism, hold the waste bottle by the grip recesses and
remove carefully.
- Discard in accordance with local regulations.
- Prepare a new waste container by taking one of the empty S1 fluid bottles and
preparing it by removing the sticker to reveal a ‘Waste’ sticker underneath.
- If there are no spare waste bottles or empty S1 bottles, the waste container can be
emptied for re-use. (Refer to Roche manual for instructions).
- Insert the bottle into the waste bottle position until it engages.
- Close the docking mechanism
- The fill-level monitoring feature recognizes the waste container as ‘empty’. If the
waste container to be used is not empty press: waste fill level, and enter the fill
level (a scaling on the container label gives an approximate value).
- Close the bottle compartment cover.
2. Check the printer paper:
-
Lift the grey cover towards the back of the right hand side of the analyser.
Check there is sufficient printer paper.
If insufficient, see below.
To change the printer paper
-
-
Remove the printer cover
Open the paper lid
Lift the blue lever to release the paper
Remove the empty paper roll
Ensure the paper has a clean leading edge to help start the paper through the
rollers. If necessary, cut the paper at a right angle.
Place the new paper roll into the holder, so that the roll feeds from the bottom
(NB the printer paper is heat sensitive on one side only).
Ensure that the blue printer lever is in the down position.
Feed in the beginning of the paper according to the instructions on the inside of the
lid.
The paper is automatically pulled into the printer. If the paper is pulled in incorrectly,
open the paper cover, open the printer lever and realign the paper, close the printer
lever and close the paper lid again.
Close the paper lid
If you are having difficulties, refer to the Roche OMNI-S/Cobas b221 Manual.
3. ISE + Blood Gas Wetting Routine (lab analyser only)
-
From ready screen press: System > Utilities > Fluid Actions > Wetting Routines
Printed copies are uncontrolled unless there is an allocated Copy Number on page 1
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RUH Bath NHS Foundation Trust – Pathology Department
STANDARD OPERATING PROCEDURE
SOP/POCT/15/16
Title: OMNI-S+COBAS b221 Point of Care
Analysers
-
Effective date: 28/07/15
Select: Automatic
Select ISE from list > DO
Attach sample container – ampoule adapter in serum sample
Aspirate sample
Analyser holds sample for approximately 1 minute to wet electrodes
Repeat procedure for BG
Back arrow out of the screen once wetting complete
Press analyser mode (top left icon) to return to ready screen
8.2 Weekly Maintenance
1. Checking the QC inventory (lab staff only)
-
Press:
-
Pull out the AQC drawer (located on the left-hand side of the analyser)
The ‘mat change’ screen appears, showing how many vials of each QC material,
level and lot no. are left on each mat.
If more mats need to be added:
NB:
QC requires refrigeration. It is guaranteed stable on board the analyser for 28 days.
Therefore, only one full mat of each level should be on board at any one time. Place a
second mat on only when the first mat is down to 2 or 3 ampoules.
-
NB:
Remove the empty mat from the holder.
Replace with a new mat of the same level and lot number, checking that the necks
of the ampoules are free of air bubbles.
Press: Refill
The screen will then prompt you to check that the lot number is the same
Press: Yes
If the mat that you are putting in is not completely full (eg due to breakage), press:
Details. By pressing the corresponding key, the status of the selected ampoule can
be changed.
Close the AutoQC drawer.
When a new reagent order is imminent, there may be no new mats to put on. This is not
usually a problem, but inform a senior member of staff if this is the case!
Record QC usage in the stock control book
If the new mat is a different lot no. from the existing lot.
- refer to the SOP for New Lot Numbers of QC (Appendix)
Printed copies are uncontrolled unless there is an allocated Copy Number on page 1
Author: M. Stubberfield
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Approved by: H Witham
Page 13 of 29
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Title: OMNI-S+COBAS b221 Point of Care
Analysers
Effective date: 28/07/15
2. Setting up the AQC Timer (lab staff only)
This should not need adjusting, but if the information is somehow lost and needs
reprogramming
Press:
>Times & intervals > QC timing
A little marker (‘QC’) on the timescale indicates the defined start time(s) and for a better
coordination with the QC timing, little markers on the timescale also indicate the defined
calibration intervals (System cal = red, 2P cal = green)
If adjustment is required, refer to Roche Manual ‘Instructions for use’ and select the start time
and the appropriate QC level(s) for each day. (M-1, 2+3; Tu, Th +Sa – 1+2; W, Fri,+ Su-1+3).
3. Cleaning Sample Fill Port/T/D Disk (Cobas b221 analysers only)
N.B. WARD ANALYSERS ONLY: The ‘LOG OFF’ TIMEOUT needs to be extended
from 60s for maintenance
-
Press: Log on User
Type in Operator ID (lower case), enter.
Scan in operator barcode as the password, enter.
-
Select: Setup
Select: Times & Intervals > Timeouts > Log Off User
Edit time to 6000s
Carry out maintenance as below
Remember to repeat procedure to change ‘Timeout’ time back to 60s when finished
-
Press:
to log off
Press: Yes to Log Off when finished
Maintenance:
-
System > Utilities > Maintenance
Press:
Arrow down to: Change Fill Port (even though only cleaning is being done)
Press: Do and carry out cleaning of fill port and T+D disk as follows:-
-
Pull the sample drip tray forward to remove it from its slot.
Clean the drip tray and fill port with a disinfectant wipe (alcohol free).
Remove the T/D unit cover.
Remove the fill port by rotating the white holder 90º downward and pulling it gently
towards you (you may need to gently wiggle it, taking care not to bend the needle
which goes into the back of the holder).
Use the fill port holder as a tool to turn the screw of the T/D by 90º.
-
Printed copies are uncontrolled unless there is an allocated Copy Number on page 1
Author: M. Stubberfield
Checked by: H. Witham
Approved by: H Witham
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STANDARD OPERATING PROCEDURE
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Title: OMNI-S+COBAS b221 Point of Care
Analysers
-
Effective date: 28/07/15
Remove and clean/decontaminate the front and back of the T/D disk with a
disinfectant wipe (alcohol free).
Re-assemble the parts in the reverse order.
Press: Continue
Please Wait is displayed while an automatic T+D disk initialisation is carried out
Press the ‘back page’ icon until Wait for Ready is displayed
The analyser will then carry out a wash before returning to the Ready screen
N.B. This procedure can be used to change the fill port, T+D disk or needle – see
Section 8.6 - As Required Maintenance.
4. Clean the touch screen
- Press and hold the corner of the touch screen firmly with one thumb to disable the
screen
- Clean/decontaminate the screen with a disinfectant wipe (alcohol free).
- Do not use water and sprays!
5. Cl- Electrode Cleaning – ITU Only
- Remove the top cover of the analyser.
- Open the measuring chamber (MC) of the ISE module by pressing on the right edge
and moving it to the left.
- Open the grey locking lever.
- Lift out the Cl- electrode – being careful to hold it by the flat plastic tab end only – do
not touch the metal contacts.
- The electrode is cleaned with a thread from the Cl- electrode cleaning kit (stored on
the blood gas analyser trolley).
- Using the waxed end of a cleaning thread, insert it into the left hand side of the
sample channel and pull it slowly and carefully through the sample channel in the
direction of the arrow - as shown in the diagram below.
CL- ELECTRODE CLEANING
-
Re-install the electrode into the measuring chamber.
Push all electrodes slightly to the right so that they are lined up together without
gaps.
Close the grey locking lever.
Close the measuring chamber.
Replace the top cover.
Printed copies are uncontrolled unless there is an allocated Copy Number on page 1
Author: M. Stubberfield
Checked by: H. Witham
Approved by: H Witham
Page 15 of 29
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STANDARD OPERATING PROCEDURE
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Title: OMNI-S+COBAS b221 Point of Care
Analysers
Effective date: 28/07/15
8.3 Monthly Maintenance
1. Check/Adjust Date and Time.
> Times and intervals > Current date & time
Press
- Check the displayed date and time are correct.
- If required press: Set date and adjust
- If required press: Set time and adjust
This process is important due to the reagent registration and expiry times.
2.
Change/Clean Waste Separator/Sensor
N.B. WARD ANALYSERS ONLY: The ‘LOG OFF’ TIMEOUT needs to be
extended from 60s for maintenance (see weekly maintenance procedure)
-
A cleaned waste separator is kept in the lab to exchange for the dirty one – stored in
the ‘Cleaned Waste Separator’ box in the blood gas store room
N.B. First deactivate the analyser by opening the reagent compartment door
Remove the top cover of the analyser
The waste separator is the plastic dome positioned at the front left of the analyser
The waste sensor is the dome-shaped plastic piece situated inside the waste
separator, with wires at the base providing the electrical connection
Remove the waste separator by turning anti-clockwise and lifting out of its location
Disconnect all the attached tubing
Remove the waste sensor by pressing evenly on the lugs at either side of the base
and carefully levering it out of the waste separator – N.B. Do not pull on the wires
Clean the waste sensor by wiping with a moist paper towel and moisten the black oring at the base to make re-insertion easier
Exchange the dirty waste separator for the clean one, ensure the white plastic insert
is in the top channel, and re-attach all the waste tubing
Insert the waste sensor into the clean waste separator – press on the lugs at the
base and push the sensor in evenly, making sure it is fully inserted
Relocate the waste separator by inserting the lugs at the base into the original
location and turn clockwise to re-seat
Carry out a Vacuum Pressure Check → System → Component Test → Control
Sensors → Vacuum System
Change the ‘Low Pressure’ to ‘MAX’ in the bottom box
Turn the vacuum pump ‘ON’
The Low Pressure reading should change to ≈ 800 – 900 mbar
Turn vacuum pump ‘OFF’ – the Low Pressure reading should slowly decrease
Back arrow through the screens to return to the Ready screen
Replace the analyser cover and close the reagent compartment door
Clean the dirty waste separator by soaking in deproteiniser for 2 hours, or until it
looks clean, and then rinsing in tap water
Printed copies are uncontrolled unless there is an allocated Copy Number on page 1
Author: M. Stubberfield
Checked by: H. Witham
Approved by: H Witham
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Analysers
-
Effective date: 28/07/15
Leave to air dry and then store in the ‘Cleaned Waste Separator’ box ready for reuse
3. Change MSS Cassette (Cobas b221 analysers only - every 28 days)
N.B. WARD ANALYSERS ONLY: The ‘LOG OFF’ TIMEOUT needs to be extended
from 60s for maintenance (see weekly maintenance for procedure)
MSS cassettes are stored at 2 – 8OC in the main cold room storage – these must be
allowed to equilibrate to room temperature for a minimum of 30 minutes, but ideally for 2
hours, before installation.
MSS Module Cleaning
- MSS module cleaning should be performed before every MSS cassette exchange,
but not more than once per month.
- N.B. Cleaning destroys the MSS cassette therefore DO NOT clean a new
cassette
- Press: System > Wash & Cleaning > Cleaning Modules
- Select MSS module
- Press: Start External Cleaning and aspirate deproteiniser using an ampoule
adapter
- Proceed to change MSS cassette
Change MSS Cassette
- Remove the top analyser cover.
- Open the MSS module cover.
- Open the contact clip and the locking lever.
- Push the reference electrodes slightly to the left and remove the MSS cassette.
- Hold the MSS cassette by the designated handle only, and avoid touching the
contacts.
- Insert the new MSS cassette and close the locking lever and the contact clip.
- Read in the barcode from the MSS cassette packaging
- Close the measuring chamber and top cover.
- Follow the instructions on screen to carry out an MSS cassette polarisation.
- Insert a serum or whole blood sample (lithium heparin sample <24 hrs old) via an
ampoule adapter
- The MSS cassette is subsequently exposed to liquid, polarised, heated and
calibrated.
- If the automatic polarisation is not successful and the MSS parameters are not
calibrated, a manual polarisation must be performed :-
Starting from
analyzer mode.
-
Press: System > Utilities > MSS polarisation.
Follow instructions on screen.
For ITU Only, turn off the glucose reporting (see instructions below)
All 3 QC levels must be performed after every MSS cassette exchange.
Printed copies are uncontrolled unless there is an allocated Copy Number on page 1
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Checked by: H. Witham
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RUH Bath NHS Foundation Trust – Pathology Department
STANDARD OPERATING PROCEDURE
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Title: OMNI-S+COBAS b221 Point of Care
Analysers
Effective date: 28/07/15
N.B. ITU Only - Turn off Glucose reporting after MSS Cassette Change
When the MSS cassette is changed, the glucose reporting automatically turns back on,
so it needs to be switched back off.
-
Press: Setup
> Parameters > Miscellaneous settings
Select Glucose in parameter list
Turn off all switches (switch from green to red)
8.4 Three-Monthly maintenance
1.
Change the Prefilter
-
2.
Pull out the air filter from its holder on the rear of the instrument.
Date a new filter and replace in the holder.
Calibrate the CO-OX Module
-
Remove an ampoule of tHb calibrator from the package and shake carefully.
Tap gently to remove any liquid from the head of the ampoule and carefully break it
open.
- Insert an ampoule adapter into the ampoule.
- Press: System > Cal > COOX Cal > Start
- Using the keyboard icon, enter the ‘tHb (target value) in g/L’, g/dl figure is printed
on the calibrator ampoule label – multiply x 10 to get g/l value.
- ‘Cuvette replaced?’ – press: No
- Results for the measured and target values will be displayed (+/- 10% is acceptable)
- Press: Accept – the calibration values are saved and used to calculate the layer
thickness of the cuvette.
- If the cuvette has been replaced, CO-OX calibration performed appears instead of
the calibration value.
- If the calibration is not acceptable, press: Reject. The module is not calibrated and
is transferred to an alarm state. A recalibration should be performed. If problems
persist, contact Roche for advice.
- N.B. Run all 3 levels of QC after completion of the Co-Ox calibration
8.5 Six - Monthly Maintenance
Change the Peristaltic Pump Tubes.
-
OMNI-S – Main peristaltic pump only - top left-hand corner of the instrument.
-
Cobas b221 – 3 peristaltic pumps (from left to right):- A. Main pump
- B. MSS output pump
- C. MSS input pump
Printed copies are uncontrolled unless there is an allocated Copy Number on page 1
Author: M. Stubberfield
Checked by: H. Witham
Approved by: H Witham
Page 18 of 29
RUH Bath NHS Foundation Trust – Pathology Department
STANDARD OPERATING PROCEDURE
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Title: OMNI-S+COBAS b221 Point of Care
Analysers
-
Effective date: 28/07/15
Quick Access > Maintenance
Press:
Select the appropriate pump tube to be changed and press Do
Remove the analyser cover.
Open the tension lever (clear plastic cover).
Push the white plastic linear bracket upwards
Remove the old tubing.
Check if the five rollers are easily moveable (in case of malfunction, call Roche).
Place the new tubing set around the rolling wheel (with the arrow on the grip
pointing upwards).
Close the tension lever.
Select Continue to start initialising routine.
Press the back page icon until the ready screen is reached.
The analyser will go into a System Cal.
Replace the analyser cover.
8.6 As Required Maintenance
1.
Replace the fill-port
If the fill-port becomes damaged, remove, as in weekly cleaning maintenance, and
replace with a new one.
2.
Replace T/D disk
If the T/D disk becomes damaged e.g. cracked, or does not function properly, remove,
as in weekly cleaning maintenance, and replace with a new one.
3.
Replace Electrodes
-
Remove the top cover and open the measuring chamber cover of the corresponding
measurement module, the following screen appears, for the appropriate module.
-
Open the locking lever on the left hand side of the module.
Printed copies are uncontrolled unless there is an allocated Copy Number on page 1
Author: M. Stubberfield
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Approved by: H Witham
Page 19 of 29
RUH Bath NHS Foundation Trust – Pathology Department
STANDARD OPERATING PROCEDURE
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Title: OMNI-S+COBAS b221 Point of Care
Analysers
-
4.
Effective date: 28/07/15
Take hold of the appropriate electrode, move it to the left, and remove it.
If removing the reference electrode, remove the white connector from the measuring
chamber cartridge
If necessary, clean the measuring chamber with a tissue moistened with 70%
isopropanol
Hold the new electrode vertically and tap lightly with a fingernail to remove any air
bubbles from the internal electrolyte solution.
Insert it into the measuring chamber according to the colour code.
If replacing the reference electrode, attach the white connector at the end of the
tube to the measuring chamber cartridge and insert the tube into the tube-guide
channel
Push all electrodes slightly to the right so that they are all lined up together without
any gaps.
Close the locking lever and run a finger along the top of the electrodes to check that
they are correctly placed.
Scan the barcodes located on the inner packaging of the electrode (or enter
manually having pressed the ‘keyboard’ icon if the scanner is not working)
The replaced electrode is shown slightly lower than the others displayed on the
screen.
Read: Next actions, their duration, and the sensor data.
Close the measuring chamber and then the top cover.
A calibration is performed following a warm-up phase.
After the calibration is complete, perform a QC measurement on all 3 levels.
Print a Status Report
To print a status report:
> Miscellaneous reports > Status report >
Press:
And then: Times and Intervals, Parameter Info, and Misc Settings and Infos in turn.
Store the resulting printouts with the disk in the AQC drawer.
9. SAMPLE REQUIREMENTS
Biological material must be considered potentially infectious and handled with proper
precautions. There is low overall risk if the test is performed using good working and safe
laboratory practice. (Refer to Health and Safety Policy Documents)
Specimen Collection and Handling: Blood Gases
Whole blood samples are used, drawn into heparinised syringes or capillaries. Samples should
be analysed as soon as possible after collection. Air bubbles should be removed from the
Printed copies are uncontrolled unless there is an allocated Copy Number on page 1
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STANDARD OPERATING PROCEDURE
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Title: OMNI-S+COBAS b221 Point of Care
Analysers
Effective date: 28/07/15
sample collection container immediately after sampling, and the sample mixed with the
anticoagulant by rolling between both hands.
Syringe samples that are not analysed immediately should be sealed and placed on an ice
slurry - stable up to 1 hour maximum.
Capillary samples that are analysed within 15 minutes may be retained at room temperature,
but should be sealed with end caps. If unable to analyse within 15 minutes, place sample on an
ice slurry – stable up to 1 hour maximum.
Lithium heparin or balanced heparin salts are the only acceptable anticoagulants for Blood Gas
and ISE analysis. Other anticoagulants such as EDTA, citrate, oxalate, fluoride and
anticoagulants containing ammonium have a significant effect on blood pH and should not be
used.
Specimen Collection and Handling: Electrolytes
Electrolytes can be measured on samples collected as above for blood gases and also on
heparinised whole blood in a lithium heparin vacutainer and on serum.
Specimen Collection and Handling: Bicarbonate (cHCO3-st)
Bicarbonate can be calculated on serum and plasma samples, ie: it is not a measured
parameter.
Standard bicarbonate of the blood, is defined as the plasma bicarbonate concentration in blood
which has equilibrated at 37°C with a gas mixture having a PCO2 = 40mmHg
Specimen Collection and Handling: Ionised Calcium
Blood should be collected into a Lithium Heparin (green top) vacutainer, which should be
completely filled. This should be analysed immediately at point of care, or transported to the
laboratory on ice, in order to minimize metabolism. The whole-blood sample should be
analysed as soon as possible after receipt.
N.B. A part-filled vacutainer is not acceptable as this increases the final concentration of
heparin in the tube to levels that can significantly lower the free calcium levels. Likewise, many
widely used blood gas syringes contain concentrations of heparin which can lower the free
calcium by 15 – 25%. Liquid heparin can result in the inaccurate measure of low free calcium
levels because of both dilution and high final concentrations of heparin.
Specimen Collection and Handling: Haemoglobin derivatives
There are no special requirements for sample handling – samples should be well mixed before
analysis.
Haemoglobin derivatives, predominantly Co-Hb, can be measured on samples collected as
above for blood gases and also on whole blood in an EDTA tube.
Printed copies are uncontrolled unless there is an allocated Copy Number on page 1
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RUH Bath NHS Foundation Trust – Pathology Department
STANDARD OPERATING PROCEDURE
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Title: OMNI-S+COBAS b221 Point of Care
Analysers
Effective date: 28/07/15
Specimen Collection and Handling: Pleural Fluid pH (Lab Analysis only)
Pleural fluid pH must be measured on an anaerobic (capped) syringe sample sent to the
laboratory on ice. This sample type is stable for 2 hours. It must be stated in the clinical details
that the sample has a minimal risk of TB.
Specimen Collection and Handling: Bilirubin (neonatal)
Whole blood samples for the analysis of bilirubin, must be treated as light sensitive:
- Transport the sample container protected from light
- Avoid direct sunlight
- Samples should be analysed immediately after collection
Specimen Collection and Handling: Glucose and Lactate
There are no special requirements for sample handling.
Samples should be analysed immediately after collection, since sample metabolism causes:
- A decrease in the glucose concentration within a few minutes of collection
- An increase in the lactate concentration within a few minutes of collection
10. PATIENT TESTING
N.B. Patient results should be reviewed and acted on by appropriately qualified staff with
particular reference to patient's history.
Repeat spurious results/results that do not fit the clinical picture.
Confirm abnormal results by sending a sample to the lab.
Neonatal Bilirubins - neonatal staff should refer to the following RUH Neonatal Protocols
before carrying out bilirubin analysis:NEO-007 - Jaundice in Neonates
NEO-005 - Exchange Transfusion of the Newborn.
A measurement can be started when the fill port is open, the status window displays: Ready,
and the parameter button is green.
N.B. a minimum volume of 40μl of sample is required per module, even if only one
parameter from that module is being measured. Deselect any modules that are not
required.
N.B. If an insufficient/inadequate sample has been obtained and the sample fails to be
analysed, a repeat sample will have to be obtained from the patient in order to repeat the
test(s) – and this must be recorded in the patient’s notes – and recorded as an incident
in Datix if appropriate.
10.1 Capillary Measurement
- Attach a clot catcher to the capillary
- Insert the capillary into the sample port
- If the position is correct, the T/D will be backlit in green and the
Measurement screen appears.
- Press: Aspirate Sample until a beep is sounded.
Printed copies are uncontrolled unless there is an allocated Copy Number on page 1
Author: M. Stubberfield
Checked by: H. Witham
Approved by: H Witham
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STANDARD OPERATING PROCEDURE
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Title: OMNI-S+COBAS b221 Point of Care
Analysers
-
Effective date: 28/07/15
Remove the capillary when prompted, and measurement will start.
10.2 Syringe Measurement
- Mix the sample well and expel any air and the first few drops of blood to
eliminate clots
- Attach a clot catcher
- Press the syringe firmly to the fill port.
- If the position is correct, the T/D will be backlit in green and the
Measurement screen appears
- Inject the sample slowly until a beep is sounded.
- Remove the syringe when prompted and measurement will start
10.3 Small Syringe Samples (<100μL)
- Mix the sample well, and expel any air and the first few drops of blood to
eliminate clots
- Attach a clot catcher
- Press the syringe firmly to the fill port. If the position is correct, the T/D will
be backlit in green and the Measurement screen appears.
- Inject the sample slowly until you have injected it all.
- There will be no beep for small samples
- Remove the syringe from the fill port and press: Aspirate Sample on the
screen.
- The sample will be moved forward to the optical sensors and on to the BG
module and then on to the other modules, depending on the volume of the
sample available.
- Alternatively, deselect any modules not required on the sample to make sure
that you get the most urgent results (min. 40μL per module).
- Remove the syringe when prompted and measurement will start.
10.4 Bicarbonate (cHCO3-st)(Lab only)
Bicarbonate can be calculated on serum and plasma samples
- Select the Bicarbonate panel
- Place either an ‘Adapter for sample Containers’ or an ‘Ampoule Adapter’
into the fill port.
- Place the other end of the adapter into the serum or plasma sample
- Press: Aspirate
- Remove the sample when prompted, and measurement will start
NB: Analysing small/paediatric samples for Bicarbonate
- Select the Bicarbonate panel
- Fill a blood gas capillary to the first line (50µl) with serum/plasma.
- Introduce the capillary to the fill port.
- Press: Aspirate
- Remove the capillary when prompted, and measurement will start
10.5 Pleural Fluid pH syringe sample (Lab only)
- N.B. Goggles must be worn when analysing pleural fluid samples
Printed copies are uncontrolled unless there is an allocated Copy Number on page 1
Author: M. Stubberfield
Checked by: H. Witham
Approved by: H Witham
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STANDARD OPERATING PROCEDURE
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Title: OMNI-S+COBAS b221 Point of Care
Analysers
-
Effective date: 28/07/15
Attach a clot catcher
Select the Pleural Fluid panel
Press the syringe firmly to the fill port.
If the position is correct, the T/D will be backlit in green and the
Measurement screen appears
Inject the sample slowly until a beep is sounded.
Remove the syringe when prompted, and measurement will start.
10.6 CO-Hb EDTA sample
- N.B. EDTA samples must not be put through any modules except the COOX
- Select the ‘CO-OX’ panel (to de-activate the other modules)
- Place either an ‘Adapter for sample Containers’ or an ‘Ampoule Adapter’ into
the fill port.
- Place the other end of the adapter into the EDTA sample
- Press: Aspirate
- Remove the sample when prompted, and measurement will start
10.7 Neonatal Bilirubin sample (Lab only)
- If sufficient sample – run on modulars – code ‘BIL’
- If small sample – run whole blood sample on lab blood gas analyser – code
‘BAB’
- 40ul minimum whole blood volume required for analysis on blood gas
analyser
- Select ‘CO-OX’ only panel button (includes bilirubin)
- Mix sample well
- Run sample into blood gas capillary tube + attach clot catcher to analyse
- Do not use ampoule adapters
- All ‘BAB’ results will go to phone queue – do not need to phone NICU results
- Remember to phone all community bilirubins.
During measurement, various patient, user and sample specific data can be entered.
NB Any mandatory input fields will be displayed in red. An input must be made or the
measurement values will be rejected and will not be displayed or printed
Press the ∆ and ∇ keys to select an entry. Press: Set input value to modify the highlighted
entry (a keyboard appears on the screen). If the patient is not yet registered (on the analyser),
press: New patient - and the patient related data will be stored.
After completion of measurement and input of all data, the results will be displayed on the
screen and printed
When the measurement and clean-up are complete, the analyser will revert back to the ‘Ready’
screen.
Ward patient results should be transcribed into the patient’s notes, along with the date/time
performed, location of the analyser and the operator signature.
Printed copies are uncontrolled unless there is an allocated Copy Number on page 1
Author: M. Stubberfield
Checked by: H. Witham
Approved by: H Witham
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STANDARD OPERATING PROCEDURE
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Title: OMNI-S+COBAS b221 Point of Care
Analysers
Effective date: 28/07/15
Lab results should be entered into Ultra.
The sample can be disposed of immediately into a burn bin, according to local health and
safety guidelines. (Refer to Health and Safety Policy Documents).
11.
11.1
REPORTING AND INTERPRETATION
Interferences
Contaminating the blood sample with air will significantly distort the blood gas measurements.
Transport of the sample to the laboratory via the pneumatic tube system can also affect these
parameters, particularly pCO2. Any substance which affects the pH of a sample (eg Aspirin)
will affect the iCa due to changes in the dissociation equilibrium. In all cases, the notes and
restrictions, such as anticoagulant type in the ‘Specimen Collection and Handling’ section
should be observed.
Various drugs and dyes can cause interference with some parameters, please refer to the
Roche Operator Manual for full details.
The user should be immediately informed of abnormal deviations of the measurement results,
and evaluate the complete picture of the patient or perform expanded tests if necessary.
11.2
Analytical ranges
Blood gas module
PO2
0 – 106.4 kPa
PCO2
0.53 – 26.6 kPa
pH
6.0 – 8.0
ctCO2
mmol/L
BE
mmol/L
Co-oximetry module
tHb
30 – 250 g/L
HHb
0.0 – 100.0 %
COHb
0.0 – 100.0 %
MetHb
0.0 – 20.0 %
Bilirubin
51.3 – 855 µmol/L
Electrolyte module
Na
20 – 250 mmol/L
K
0.2 – 20 mmol/L
Cl
20 – 250 mmol/L
iCa
0.1 – 4.0 mmol/L
MSS Module
Glucose
Lactate
0.5 – 40 mmol/L
0.2 – 20 mmol/L
Printed copies are uncontrolled unless there is an allocated Copy Number on page 1
Author: M. Stubberfield
Checked by: H. Witham
Approved by: H Witham
Page 25 of 29
RUH Bath NHS Foundation Trust – Pathology Department
STANDARD OPERATING PROCEDURE
SOP/POCT/15/16
Title: OMNI-S+COBAS b221 Point of Care
Analysers
11.3
Effective date: 28/07/15
Reference ranges
Please refer to the Operator’s Manual (QPulse external document EXT/BIO/14)
11.4
Results Entry
Wards Only
Results must be transcribed into the patient’s notes – rather than inserting the print-out – as the
paper is heat sensitive and the print fades with time. The date/time of analysis and the location
of the blood gas analyser used must also be included, as well as the signature of the operator
carrying out the analysis.
Lab Only
The results are entered into ‘Ultra’ using the ‘Vertical Result Entry’ program, taking care not to
make any transcription errors.
Blood Gases:
• pH
• pCO2
• pO2
• ctCO2
• BE
kPa
kPa
mmol/L
mmol/L
Pleural Fluid pH
• pH
Bicarbonate
• cHCO3- mmol/L
Carboxyhaemoglobin
• COHb %
Bilirubin
• Bili
µmol/L
• Any results outside pre-determined limits will go to the ‘Telephone Queue’ for
telephoning to the requesting ward / doctor.
11.5
Limitations
Haemoglobin
The Hb result obtained from the Cobas b221/Omni S blood gas analysers must not be used in
direct patient care – it is to be used as a guide only.
If an Hb is required for direct patient care then an EDTA sample must be sent to the lab.
Any individual using the blood gas analyser Hb in patient care will be responsible for their own
actions.
Printed copies are uncontrolled unless there is an allocated Copy Number on page 1
Author: M. Stubberfield
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Page 26 of 29
RUH Bath NHS Foundation Trust – Pathology Department
STANDARD OPERATING PROCEDURE
SOP/POCT/15/16
Title: OMNI-S+COBAS b221 Point of Care
Analysers
Effective date: 28/07/15
Glucose
Roche state in the Cobas b221/Omni S blood gas analyser Operator manual that:
Due to the current specifications, clinically significant deviations in the range <3 mmol/L can
occur compared to other glucose measuring systems, especially in the neonatal field.
This means that for any patient samples that produce a result of <3 mmol/l a repeat sample
should be sent to the lab for confirmation.
(NICU were informed of this when the Cobas b221 gas analysers were installed in Feb 2010)
12. REFERENCES
1.
2.
3.
4.
Roche OMNI-S/Cobas b221 Reference Manual
Roche OMNI-S/Cobas b221 Instructions for Use
Principles & Practice of Point-of-Care Testing. Edited by: Gerald J.Kost
Tietz Textbook of Clinical Chemistry; Burtis, Carl A., PhD; Ash, Edward R., M.D., 3rd edition.
Printed copies are uncontrolled unless there is an allocated Copy Number on page 1
Author: M. Stubberfield
Checked by: H. Witham
Approved by: H Witham
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RUH Bath NHS Foundation Trust – Pathology Department
STANDARD OPERATING PROCEDURE
SOP/POCT/15/16
Title: OMNI-S+COBAS b221 Point of Care
Analysers
Effective date: 28/07/15
APPENDIX - New Lot Number of IQC
If the new mat is a different lot no. from the existing lot no:
- To ‘empty’ the mat position in the AQC drawer of the old lot no
press:
Setup > QC material > QC material
-
Select the lot no/level of the old material and press: Mat
Select the mat you want to remove and press: Delete
Press: Back-a-page to save
The new lot no. of AQC can be added in 2 ways:
1. QC Setup Wizard:-
-
2.
The quickest way to start the QC Setup Wizard is:
Open the AQC drawer
Select: Yes to the query: Start up QC Wizard? (Yes or No)
Scan in new material barcode as instructed
Press: Continue
Select lot no. for change lot – select the in use lot no. if not already selected
Select: Continue with lot change
Scan in additional barcodes for the ranges (or enter manually)
Press: Continue
Assign Mat – Press: Set under the mat to be used for the new lot no.
Insert new mat in correct position and close AQC drawer
Material was successfully installed – will be displayed – check material details on
screen are correct
Select: Exit – or – Read in additional material if required
N.B. It is necessary to go back in to QC Material → Ranges, to delete some
analytes as follows:
LAB/A+E/MAU/NICU - Delete Cl- line on ranges screen, as Cl- not in use in these
departments
ITU – Delete Glucose and Bilirubin lines on ranges screen, as these analytes are
not in use in IT
Press the Back-a-page icon to save changes then press the Return to front
screen icon to finish.
Manually:- Select the level of the new material to be entered and press: Set
- Scan in the material code on the pack insert, or press: New and enter the
information manually. The material code contains the information for the material,
level, lot number, expiration date and sample types.
- Press: Back-a-page to save
- Press: Ranges and scan in the additional barcodes for the ranges (or enter
manually).
Printed copies are uncontrolled unless there is an allocated Copy Number on page 1
Author: M. Stubberfield
Checked by: H. Witham
Approved by: H Witham
Page 28 of 29
RUH Bath NHS Foundation Trust – Pathology Department
STANDARD OPERATING PROCEDURE
SOP/POCT/15/16
Title: OMNI-S+COBAS b221 Point of Care
Analysers
-
-
Effective date: 28/07/15
N.B. LAB/A+E/MAU/NICU - Delete Cl- line on ranges screen, as Cl- not in use in
these departments
N.B. ITU – Delete Glucose and Bilirubin lines on ranges screen, as these analytes
are not in use in IT
Press Back-a-page to save
Assign Mat - Select the new material from the list and press: Mat
Select the required mat position from the list and press: Set
Press: Back-a-page to save the material assignment.
Press:
to return to the top level of setup mode.
Press:
to return to analyser mode.
Pull out the AutoQC drawer – the mat change screen appears.
Take a full mat of QC ampoules from the package and, checking that the necks of
the ampoules are free of air bubbles, place in the defined position of the ampoule
block.
Press: Refill. (NB incomplete mat details can be entered by pressing Details at this
point and amending as necessary)
OMNI-S prompt: ‘is the material the same lot number?’ press ‘Yes’
Close the Auto QC drawer.
Press
>QC material>change lot
Tab down to the current lot and press Select new lot no (OMNI-S/Cobas b221 will
automatically go on to use this lot number when the current one has finished and
will replace it in the QC timer setup)
Press the Back-a-page icon to save changes then press the Return to front
screen icon to finish.
If the Auto QC Timer Setup is lost:
Refer to Roche OMNI-S/Cobas b221 Instructions for Use Manual for details on how to
reprogramme it, selecting the appropriate start time(s) (15 minute increments between each
level) and QC levels for each day (M-1,2+3; Tu,Th + Sa 1+2; W,Fri + Su 1+3).
Copy number
1
2
3
4
5
Location held
Lab – Omni – S SOP Folder
NICU – Cobas b221 SOP Folder
A+E – Cobas b221 SOP Folder
MAU – Cobas b221 SOP Folder
ITU – Cobas b221 SOP Folder
Printed copies are uncontrolled unless there is an allocated Copy Number on page 1
Author: M. Stubberfield
Checked by: H. Witham
Approved by: H Witham
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