Specific instructions for the patient

As a patient, there are withdrawals that you perform yourself at the request of your doctor. Always try to perform these samplings as correctly as possible.
You can find the necessary instructions on this page.
Should you still have questions about this, you can always contact your doctor.
Below is an explanation of the complete flow that each sample must follow.

Pre-analytical phase

The cycle of laboratory analysis describes the entire process from the request for an analysis to the interpretation of the analysis result. Within this cycle, we distinguish three phases:

• Pre-analytical phase
• Analytical phase
• Post-analytical phase 

The pre-analytical phase includes everything that precedes the analysis, such as test requests, patient preparation, sample collection, sample identification, sample storage and transport.
The analytical phase includes the actual determination in the laboratory and is monitored through quality control.
The post-analytical phase consists of everything that follows the analysis in the laboratory, such as the medical interpretation and validation of the results and the reporting of those results.

Pre-analytical factors that can lead to errors:

• incorrect preparation of the patient (e.g. not fasting)
• inadequate or incorrect sample collection
• incorrect patient identification
• sample mix-up
• inadequate sample storage and/or transport 

Questions to be answered before requesting an analysis:

• what are the clinical symptoms and medical question?
• what is the differential diagnosis?
• which laboratory tests are useful in this case?
• how should the patient be prepared?
• how should the sample be taken, stored and transported? 

Detailed information on sample material, storage and transport can be found in the Lab Guide. An overview of the sample collection instructions can be found at the bottom of this page.

Identification of samples

This is necessary and very important. It is a legal obligation to identify samples unambiguously. The person collecting the sample should, in the presence of the patient, check that the patient’s identification details correspond to those on the application form.

A correct identification procedure allows a direct link to be made between the application form and the corresponding primary samples. Therefore, please state the patient’s last name and first name on each sample and/or provide the samples with the unique blue bar codes delivered by the laboratory and place them in a plastic bag together with the application form.

Additional information

If multiple samples are taken from the same patient at different times, the date and time of collection must be stated on the various samples.
For swabs, please mention the place and depth of collection, for urine collection the duration of collection and for fluids the type (synovial fluid, lumbar fluid) on the container.

Sample storage

Medical samples must not be exposed to freezing cold or heat during the pre-analytical phase. In cases of extreme outdoor temperatures, it is recommended not to place the samples in the sample collection box, but preferably keep them indoors until the time of pickup.

(Whole)blood samples are preferably stored at room temperature (15-25°C), but for most analyses they may also be kept refrigerated (2-8°C) while awaiting analysis, for example when microbiological samples have also been taken from the patient. When there is a combination of different optimal storage conditions, it is best to choose the storage method based on the clinical priority of the requested tests.

Samples for microbiological analysis: store in the refrigerator (2-8°C).
Exceptions:

• Blood culture samples: store at room temperature
• Cerebrospinal fluid for culture: store at 37°C or at room temperature

Deep-frozen medical samples are shipped in freezing containers. For multiple analyses on the same sample, a separate aliquot (fraction) must be frozen for each analysis.

Permanent quality assurance

Carefully following the collection instructions and correctly storing the samples before they are picked up by the courier are important aspects of the pre-analytical phase.

When samples for microbiological research are not kept cool, an uncontrolled growth of micro-organisms can occur, which can lead to a distorted image of the initially present bacterial flora. Extreme temperatures should be avoided at all times for any laboratory sample.