Diagnosing Death using Neurological Criteria

< 37 weeks DNC cannot be confidently made.

37 weeks – 2 years Criteria is the same as per adults, with 3 caveats:

1. 24 hrs before testing
2. 24 hrs between testing
3. No ancillary investigation.

2 years and above Criteria as per adults.

This was a pragmatic decision by the RCPCH working group, taking together all the available evidence, combined with a desire to align more closely to international guidance, and without intending to cast doubt on any previous diagnosis of death.

Start PaCO2 ≥ 5.3 KPa

End PaCO2 ≥ 8.0 kPa, pH < 7.3 + Rise PaCO2 ≥ 2.7 kPa

Time Minimum 5 minutes

The working group had no safety concerns with the current UK apnoea test as outlined in the 2008 Code. However, the updated 2025 Code apnoea test will more closely align the UK to international practice. Particularly the requirement for end arterial blood gas targets (PaCO₂ ≥ 8.0 kPa, pH < 7.3) and including a rise of PaCO₂ ≥ 2.7 kPa (20 mmHg). Additionally the same apnoea test can now be used across all age groups, which previously wasn’t the case for the under 2 months of age.

It was accepted that with the new lower starting PaCO₂ (≥ 5.3 kPa) compared to the previous 2008 Code (≥ 6.0 kPa), some doctors may choose to delay taking the confirmatory arterial blood gas sample immediately at 5 minutes, to increase the certainty that the PaCO₂ and pH have reached the apnoea end arterial blood targets. The 5 minutes observation is a minimum.

Completion of the second set of clinical tests. If ancillary investigations are required to confirm death, and are carried out after clinical testing, the time of death will be the point at which the result of the ancillary investigation is available to the final two doctors in Test 2.

This update more closely aligns the UK to international practice, reflects the evolving recommendation for two mandated sets of clinical tests of brainstem function (2008 and 2025 Code), fits with the 2025 Code general recommendation to time death to when the healthcare professionals are satisfied all the relevant criteria to diagnose death are met, and may be more supportive of families who increasingly witness the second set of tests and often want to be with their loved one at the recorded time of death.

To date, the courts have ordinarily deferred to healthcare professionals to provide a time of death. The legal experts in the Academy working group could see no reason a change to timing death to the point when the healthcare professionals are satisfied all the relevant criteria to diagnose death are met, rather than retrospectively timing death to the conclusion of the first set of tests, would not be equally supported.

The foreword to the 2025 Code is signed by all four Chief Medical officers across the UK.

Support from the National Medical Examiner for England and Wales has been gained.

The Coronial services of England and Wales, and Northern Ireland were consulted and voiced no disagreement.

The Crown Office and Procurator Fiscal service in Scotland was consulted and voiced no disagreement.

The core temperature should be greater than or equal to 36°C at the time of clinical testing.

In patients who are hypothermic (defined as a core temperature less than 36°C), either therapeutic or accidental, a minimum 24 hour observation period is required following correction of hypothermia (that is, attaining a core temperature of 36°C or greater). Following correction of hypothermia, transient and temporary reductions in temperature do not mandate a further 24 hour observation at normothermia.

The core temperature should be greater than or equal to 36°C at the time of clinical testing.

In the case of an inability to examine both eyes or both ears, for whatever reason, ancillary investigation will be required.

Given that the eyes are required in the clinical testing of three of the six brainstem reflexes used in neurological criteria, it is recommended that it must be possible to examine both eyes and there should be no reason to suspect an eye injury or abnormality would prevent the reflex occurring if it could. In the case of an inability to examine either eye, for whatever reason, it was recommended that ancillary investigation would be required to support a diagnosis of death using neurological criteria. Similarly, both ears must be able to be accessed for the vestibulo-ocular reflex.

This change aligns the UK to other international guidance.