Frequently asked questions

Screening and randomization

What is classified as OHCA vs IHCA?

OHCA: Arrest at the ER prior to final report from paramedics, non-admitted patients/relatives/care-givers whom have a cardiac arrest at the hospital or at a doctor’s appointment, patients with repeated cardiac arrests and non-sustained ROSC (<20 min) from the first OHCA at the arrival to the ER (continued events).

IHCA: Admitted patients to the hospital who have a cardiac arrest while at the hospital.

A patient has an unwitnessed cardiac arrest and the time of cardiac arrest is unknown. What time and date should I put in the eCRF?

If the exact time of the cardiac arrest is unknown then use the time of call to the dispatch center. This time is recorded, it is accurate and included in the EMS forms.

A patient is randomized in the emergency department but on the way to the ICU has a CT brain examination performed revealing a subarachnoid hemorrhage. Should this patient be excluded from the study?

Based on the intention to treat principle, data should be collected for this patient. However, the treatment goals for MAP, sedation and temperature will be up to the treating clinician. In these cases it may be an option to slightly delay the randomization until the performance of the CT brain, if there is a clear suspicion of an intracranial hemorrhage.

Temperature

What temperature goal settings for CRRT should be applied on patients randomized to standarded temperature management without device who develop fever?

For unconscious patient who develop core temperature > 37.8°C within 72 h of being randomized to standard temperature management without device and for other clinical indications (anuric, acidic, hyperkalaemic etc) requires continuous renal replacement therapy (CRRT), the temperature goal should be as for other non-cardiac arrest ICU-patients (commonly CRRT with extracorporeal temperature management aimed at normothermia). If there is a refractory fever despite CRRT the temperature goal is to the discretion of the physician.

Is cooling with ice packs allowed?

Yes, but this method of cooling should not be used routinely in place of a device. Instead, ice packs should only be used if the body temperature is sufficiently high that it would be of clinical concern outside the context of post cardiac arrest care.

Sedation

My patient is randomized to receive minimal sedation. What if I need to perform clinical interventions or transport the patient to radiology department?

Whenever possible the sedation should be kept minimal, but if clinically indicated, sedation can be increased temporarily.

My patient is randomized to minimal sedation, but with minimal sedation or with no sedation at all, he/she is deeply comatose. Should I interpret this as deep sedation and thus protocol violation?

No, this is perfectly acceptable and belongs to the nature of the condition.

My patient is randomized to deep sedation. Should sedation breaks still be allowed daily?

No, sedation is to be kept constantly deep until the end of the 36-hour period.

Are pain medications interpreted as sedation?

No, pain should be treated as per routine practice and the patient can receive opioids if pain is adequately assessed and detected. Opiate infusions are OK if low doses are used and they are titrated to correspond to patient´s needs.

Are there any restrictions about the sedative that is used? Can inhalation anesthetics be used?

The sedative medication is according to clinical routine in each unit.

My patient is randomized to minimal sedation and has myoclonic seizures. Can I use higher doses of sedation to treat convulsions?

If the patient has seizures and other forms of antiepileptic treatments are ineffective drugs such as propofol and benzos can be used as per the treating clinician. This will be recorded in the eCRF.

My patient is randomized to deep sedation but requires high doses of propofol (>4mg/kg/hour) and propofol syndrome is clinically suspected. Should I withdraw the patient from the study?

This patient should not be withdrawn from the study. We suggest changing to another sedative.

MAP

My patient is randomized to deep sedation and high MAP. The high dose of sedative impairs the possibility to reach target MAP. Which intervention should be prioritized.

First check the volume status and cardiac function. When optimized, you may try another sedative medication. If the problem remains and the noradrenaline dose is at a very high level (approaching 1 microgram/kg/min) deemed unsafe by the treating clinician, the MAP target can be reduced at increments of 5mmHg.

When does the MAP intervention of targeting a MAP of 65 or 85 mmHg stop?

The MAP intervention stops when the patient is extubated or at 72 hours whichever occurs first. If the patient is extubated but then need to be reintubated before 72 hours then the allocated MAP target should be used. When the intervention stops the MAP target will be up to the treating clinician.

If the clinician decides that the MAP target should be modified (a lower target because of poor cardiac function and a high vasopressor need) should this be kept same for the whole intervention period?

If possible the MAP target should be reassessed every 4-6 hours and if the situarion allows (decreasing need of a vasopressor) then the allocated MAP target should be reintated.

What is the highest possible noradrenaline dose that can be used to achieve the higher MAP target?

We do not know this for sure and it may vary between patients. In the COMACARE and NEUROPROTECT trial there were patients who received up to 1 microgram/kg/min in order to achieve the higher MAP. There was no clear indication that these patients had more severe side-effect or a worse outcome. Nonetheless if the noradrenaline dose is high the patients should be assessed on a case by case basis.

What do the current international Guidelines recommend as the minimally accepted MAP after cardiac arrest?

The ERC/ESICM Guidelines (https://pubmed.ncbi.nlm.nih.gov/33773827/) recommend targeting a MAP of higher than 65 mmHg. The American Heart Association and the Neurocritical Care Society target a MAP of higher than 80 mmHg (https://pubmed.ncbi.nlm.nih.gov/38040992/) unless the patient has invasive brain oxygen monitoring. Therefore there are currently no clear scientific consensus on how to manage these patients.

Study procedures

How do we report a protocol deviation?

Protocol violations are reported through the eCRF.