Multimodal Evaluation Strategy

The key recommendations are summarised below:

1. Clinical examination

• Using the bilateral pupillary and corneal reflexes at 72 h or more from ROSC
• Prolonging observation of clinical signs beyond 72 h when interference from residual sedation or paralysis is suspected, so that the possibility of obtaining false positive results is minimised;
• Not to use absent or extensor motor response to pain (M 2) alone to predict poor outcome as it has a high false-positive rate.

2. Myoclonus and status myoclonus

• Using the term status myoclonus to indicate a continuous and generalised myoclonus persisting > 30 mins in comatose survivors of CA;
• Using the presence of a status myoclonus within 48 h from ROSC in combination with other predictors.
• Evaluate patients with post-arrest status myoclonus off sedation whenever possible.

3. Bilateral absence of Somatosensory Evoked Potential (SSEP) N20 wave

• Using bilateral absence of SSEP N20 wave at 72 h from ROSC to predict outcome in comatose survivors following CA treated with controlled temperature.
• There was suggestion to use SSEP at 24 h from ROSC to predict outcome in comatose survivors following CA not treated with controlled temperature.

4. Electroencephalogram (EEG)

• Absence of EEG reactivity to external stimuli, presence of burst suppression or status epilepticus at 72 h after ROSC to predict poor outcome in comatose survivors from CA.

5. Biomarkers

• Use high Neuron Specific Enolase at 48-72 h from ROSC.
• no threshold enabling prediction with zero false-positive results can be recommended.
• Utmost care and preferably multiple sampling should be employed to avoid false positive results due to haemolysis.

6. Imaging

• Use the presence of a marked reduction in grey matter/white matter ratio or sulcal effacement on brain CT within 24 hours after ROSC.
• presence of the extensive reduction in diffusion on brain MRI at 2-5 days after ROSC.

It is strongly recommended that the above prognostication markers should be used in combination and not independently. See Fig 1.