Timeline: The Emergency Department – Investigations

These should be undertaken using the same aseptic technique that would be used in life. Samples sites must be recorded and all samples properly documented and labelled in order to maintain an unbroken chain of evidence. This may mean handing the specimens to a police officer directly or having the lab technician sign for them on receipt.


Approx 8-10mls is needed in total.

Blood samples from an arterial or venous site. Cardiac puncture can also be used, but this should be a single attempt using a substernal approach by an experienced person.

The earlier these are done, the more reliable the results are likely to be. There is often a delay of several days before the post-mortem is performed.


Sample Purpose of test

Infection, electrolyte disturbances, renal failure, liver failure




Genetic abnormalities


Poisoning (intentional and non-intentional)

Inherited Metabolic Diseases (IMD)

Guthrie card for specific metabolic disorders

Amino Acids

Metabolic disorders

2. Cerebrospinal Fluid (CSF)

Perform an LP to screen for infection.

Send CSF for microbiology and clinical chemistry

3. Nasopharyngeal Aspirate (NPA)

Send if less than 8 hours post-mortem to identify viral infections.

4. Urine

Obtain samples from a supra-pubic aspirate, an in-out catheter or squeeze out of an unsoiled nappy.

Send for toxicology, inherited metabolic diseases and microbiology.

5. Skin biopsy for fibroblast culture

This is to identify specific metabolic and genetic disorders.

It is taken from the upper, inner arm and put in viral culture medium which is then refrigerated.

6. Full skeletal survey including a CT head

This is routine for those under 2 years. Over 2 years, this is performed on a case-by-case basis. They should be reported on by a paediatric radiologist

7. Any additional tests that may be appropriate according to the clinical presentation, e.g.

  • Bloods for carbon monoxide testing in suspected smoke inhalation
  • Microbiology swabs of any wounds
  • Muscle biopsy if there is potential of Inherited Metabolic Disease or mitochondrial disease.