The Clinical Biochemistry Laboratory aims to provide a comprehensive routine and emergency diagnostic service. In the interests of efficiency and effectiveness the service is delivered with the majority of investigations being performed in-house wherever numbers, service demands and costs allow. We are dedicated to providing the best analytical service possible. To this end there are always people available to offer advice, assistance with interpretation and help in deciding on further investigations. In the same vein, further tests will be cascaded where it is practical and will help the investigation, or removed where deemed inappropriate for that investigation. This policy depends on your co-operation in giving the relevant clinical details and sending the correct samples. It also depends on your feed-back so that we are aware of our shortcomings and can work towards continued improvement.


Clinical Biochemistry is a Consultant led service with scientific and technical laboratory staff always available to answer queries and provide help


Day to day advice can be obtained by contacting the Laboratory.  Where specialist advice on interpretation of tests, protocols and investigations is required please dial 0191 445 6499 and select option 2 for Biochemistry followed by option 2 for Clinical Advice.  Out of hours clinical advice is available by contacting the on duty Biomedical Scientist at each site.

Laboratory Hours

The laboratory is staffed to provide 24hr a day service with the following patterns:

Monday to Friday:

7am – 9am Single staff member on duty

9am – 5pm ‘Core hours’ where most staff are on duty including senior staff

5pm – 10pm Reduced staff numbers

10pm – 7am Single staff member on duty

Weekends/Bank Holidays:

Single staff member on duty

Test Repertoire

A searchable list is available in the Tests section of the website. This section will give details of tests available, collection details, reference ranges and units, telephone criteria, turnaround times and any appropriate comments.

Some tests require special sample tubes and/or conditions, e.g. Gastrin and Cryoglobulin. In these cases please contact the Laboratory BEFORE taking the sample. This is to try and ensure that correct procedures are followed and time is not wasted.

Where the test is very unusual, expensive or requires very special collection and/or transport conditions, then the request MUST be discussed BEFORE taking the sample with the Duty Biochemist.

This is to ensure the most cost effective use of the Laboratory and that the most effective tests are used for diagnosis, it is NOT meant to obstruct the process of treatment. Failure to discuss the requirements may result in the sample being held for justification, which may cause delay.

Where tests are not performed on-site these will be indicated as ‘Referred’ and the turnaround times will be listed as those given by the referral laboratory whenever available. In the absence of this information it may be based on experience and hence may be an approximation.

The referral centres employed by SoTW Clinical Laboratory Services are selected based upon their UKAS accreditation status and their ability to meet the needs of our users. The laboratory periodically reviews the quality of these referral centres.  Referred tests are indicated within the turnaround section of each individual Tests listing.

If you cannot locate any test or there is insufficient detail in this section then please contact the laboratory.

Most General Chemistries are available on an emergency basis but not the complete Laboratory Repertoire. Only tests that will have an immediate effect on patient management should be requested. Some tests cannot be done due to time, complexity, cost or analyser availability and the laboratory staff on duty should be contacted for advice.

However, as assisting in good patient care is the aim of the Laboratory, taking a little time to discuss the case with the staff on duty may result in the analysis of tests not normally available.

Urgent requests for General Chemistries will be processed straight away, where the analysis is desirable but not urgent the sample will be processed as time allows. In-Patient work will always be prioritised and key departments within the Hospitals (e.g. Casualty, Critical Care, Paediatrics) and key tests (e.g. Troponin-T, Gentamicin) will be fast-tracked at all times.


Where available, ALL the requests should be made using the appropriate electronic ordering system:

Meditech Order Management – CHS and South Tyneside Hospital requests

Clinisys ICE – GH Hospital requests. Gateshead, South Tyneside and Sunderland CCGs,



Where or when paper requests need to be used the following information is mandatory:

If the request is from inside the Hospital a contact bleep number is extremely useful.  When from a GP it should include contact information for the patient (e.g. telephone number and home address) so that the deputising service is able to deal effectively with grossly abnormal results when necessary

It is extremely important for relevant Clinical Details to be included on the request. This helps us to help you by giving advice and interpretation where necessary and to add other useful tests when indicated. The date and time the sample is taken should also be included. This is essential when interpreting certain tests.

On occasions where samples need to be written by hand they must be labelled with the patient’s full Surname and Forename, Date of Birth and date and time of collection.

All samples must be labelled with the sample label. Samples should also be taken into the correct type of tube, if in doubt refer to the Tests page or contact the Laboratory for advice. Ideally a separate sample for each department is required but there are exceptions to the rule, e.g. patients very difficult to bleed, neonates.

To safeguard patients against wrong treatment, samples with details that are grossly at odds with those on the Request Form will NOT be processed and the requesting source will be notified. In cases where there are no details on the sample:

Justification may be required for some tests. In these cases the sample will be held for a reasonable length of time to allow contact with the Duty Biochemist. This is to ensure that the most appropriate, cost effective investigations are performed.

Additional tests may be added to samples held in the department if appropriate to do so for up to 3 days after the collection date. The Addition of tests after this time will require discussion with the duty Biochemist and will depend on the availability of the sample (samples are routinely stored for 4-5 days depending on workload)

For instructions for preparation of patient (see Tests)

There are no current requirements for patient consent

Any factors known to significantly affect the performance of the examination or the interpretation of results are contained within the Tests.

All High Risk or Hazardous samples MUST be double bagged and marked as such with Danger of Infection labels.

They should never be sent to the laboratory in the pneumatic air tube system

please hand deliver them to the Laboratory wherever possible

Reference Ranges

All reported numerical results are accompanied by an appropriate Reference Range where this is applicable. This is often related to age and sex but is always a population range and not an individual range.

Adult reference ranges are given in the Tests section where appropriate.

Even if the result is within the limits quoted it may be inappropriate for a given disease state and so if in doubt please contact the Duty Biochemist.

Abnormal Results

Results that are significantly abnormal (see Tests section for “phone levels”) and not previously reported or which have changed significantly will be telephoned to the requesting location. This will be done whether or not the request has been deemed “urgent”

Where it is deemed appropriate comments and suggestions will be appended to the report, and further tests added.


 High Risk/Hazardous samples MUST be double bagged. 

The request form and sample(s) MUST be marked with ‘Danger of Infection’ labels.

Most Biochemistry samples can be sent to the Laboratory using the Pneumatic Air-Tube system, where available (follow provided instructions for use).

Samples must be appropriately sealed and bagged before sending to avoid spills/leaks.

Ensure Biochemistry and Haematology Samples are in a separate bag to Microbiology Samples. This helps easily identify samples during the initial sorting process.

NEVER send High Risk/ Hazardous samples, glass containers or CSF samples in the system, these must be delivered by hand to the laboratory.




In most cases a single 5ml SST II (13×100 Yellow Tube) or Vacuette (13×75 Gold Tube) is sufficient unless a large number of investigations are required (the ICE requesting system will indicate when more than one is required).

There are exceptions depending on test or the time the sample will take in arriving at the Laboratory, etc. These are indicated in the Tests section for the common tests. If the investigation is not found or there are any doubts, please contact the Laboratory.

For paediatrics, a 2ml serum (Gold) tube is ideal for most investigations. When a sample is limited please contact the department to inform staff of the priority of tests.

Care must be taken not to contaminate blood in a gel tube with blood from other types of tube (e.g. an EDTA sample tube) as this may lead to artefacts.


There are a few cases where specialised bottles are required, available from the Laboratory on request (see Tests Section for details). In general a fresh sample without preservative is preferred. A single urine collection should be a midstream urine into a 4ml sterile collection bottle.

Miscellaneous Fluids and Body Products

Except for CSF glucose, CSF lactate and fluid glucose; where a Fluoride-Oxalate tube is necessary; and fluid pH where a syringe is required; collect biochemistry miscellaneous fluids and body products in a 4ml sterile collection bottle.

Turnaround Times

The “Routine” General Chemistries are analysed on receipt which gives a turnaround time in the laboratory as given in the Tests section. These are expected ROUTINE turnaround times at times of normal laboratory function.

URGENT samples for General Chemistries can be turned around in less than 1 hour (may be longer to include check, repeat and cascade analysis).

Turnaround times for URGENT samples may be further reduced by using Lithium Heparin (LiHep no Gel) tubes as there is no requirement for the clotting process to occur (these tubes cannot be used for Lithium, Electrophoresis investigations).

Results are available electronically for hospital patients.

For GPs the results are sent out after validation either in printed form or electronically. Time of arrival of the results at the GP surgery will depend on a variety of circumstances (e.g. analysis time, time for authorisation, time of GP system querying the mailbox, etc.) and conspire to give a true turnaround of about 1 working day.

Other Chemistries done in-house will be batched and analysed at varying times depending on numbers, cost and ease of analysis. Where tests are referred to a reference Laboratory (very small numbers or specialised analysis), turnaround times are dependent on the Referral Laboratory. This means that turnaround can vary between 2 days to several weeks depending on the test (contact the Laboratory for any specific enquiry).

The referral centres employed by SoTW Clinical Laboratory Services are selected based upon their UKAS accreditation status and their ability to meet the needs of our users. The laboratory periodically reviews the quality of these referral centres.  Referred tests are indicated within the turnaround section of each individual test listing.

Where repeat analyses or further tests are cascaded, the turnaround may be delayed.

There is flexibility in the analysis schedule and the Laboratory is always willing to try and accommodate specific requests for faster turnaround times. When assays are not done in-house we will also try and intercede with the Referral Laboratory where there is an urgent requirement for the result. Please contact the Laboratory or the Duty Biochemist.

 Quality Assurance

The Laboratory endeavours to make quality a fundamental component of all its work, and to continually monitor its performance and improve deficiencies.

All analyses are subject to internal quality control procedures, involving analysis of “QC” samples with known values to check that the analysis remains accurate and precise.

In addition all analyses are subject to External Quality Assurance procedures involving the blind analysis of samples distributed from nationally recognised Reference Centres. These allow the accuracy and precision of this Laboratory’s results to be compared with other laboratories in the country and with reference values.

The Laboratory performance in External Quality Assurance is available on line.

Results of all Chemistries are screened by the Laboratory computer system and those with significant abnormalities or which have changed from previous results are selected for checking and authorisation by a Senior member of the Laboratory, usually the Duty Biochemist.

The Department is accredited to ISO15189:2012 and ISO22870:2016 ; our full scope of accreditation is published on the UKAS website.