Influence of Cooling Duration on Efficacy in Cardiac Arrest Patients (ICECAP)
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ClinicalTrials.gov Identifier: NCT04217551 |
Recruitment Status :
Recruiting
First Posted : January 3, 2020
Last Update Posted : May 9, 2023
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Condition or disease | Intervention/treatment | Phase |
---|---|---|
Cardiac Arrest, Out-Of-Hospital Hypothermia, Induced Hypoxia-Ischemia, Brain | Device: Therapeutic Hypothermia | Not Applicable |

Study Type : | Interventional (Clinical Trial) |
Estimated Enrollment : | 1800 participants |
Allocation: | Randomized |
Intervention Model: | Parallel Assignment |
Intervention Model Description: | Bayesian Adaptive Design |
Masking: | Single (Outcomes Assessor) |
Masking Description: | The outcomes assessors will be blinded to the treatment assignment of the participant. |
Primary Purpose: | Treatment |
Official Title: | Influence of Cooling Duration on Efficacy in Cardiac Arrest Patients - A Multicenter, Randomized, Adaptive Clinical Trial to Identify the Optimal Duration of Induced Hypothermia for Neuroprotection in Comatose Survivors of Cardiac Arrest |
Actual Study Start Date : | May 18, 2020 |
Estimated Primary Completion Date : | July 15, 2025 |
Estimated Study Completion Date : | August 31, 2025 |

Arm | Intervention/treatment |
---|---|
Experimental: 6 hours - shockable
Participants with shockable initial rhythm will be assigned to receive 6 hours of hypothermia with a target of 33 degrees followed by 6 hours of controlled rewarming.
|
Device: Therapeutic Hypothermia
Participants will receive therapeutic hypothermia for the assigned number of hours with controlled rewarming, using a closed-loop temperature control device. |
Experimental: 12 hours - shockable
Participants with shockable initial rhythm will be assigned to receive 12 hours of hypothermia with a target of 33 degrees followed by 12 hours of controlled rewarming.
|
Device: Therapeutic Hypothermia
Participants will receive therapeutic hypothermia for the assigned number of hours with controlled rewarming, using a closed-loop temperature control device. |
Experimental: 18 hours - shockable
Participants with shockable initial rhythm will be assigned to receive 18 hours of hypothermia with a target of 33 degrees followed by 18 hours of controlled rewarming.
|
Device: Therapeutic Hypothermia
Participants will receive therapeutic hypothermia for the assigned number of hours with controlled rewarming, using a closed-loop temperature control device. |
Experimental: 24 hours - shockable
Participants with shockable initial rhythm will be assigned to receive 24 hours of hypothermia with a target of 33 degrees followed by 24 hours of controlled rewarming.
|
Device: Therapeutic Hypothermia
Participants will receive therapeutic hypothermia for the assigned number of hours with controlled rewarming, using a closed-loop temperature control device. |
Experimental: 30 hours - shockable
Participants with shockable initial rhythm will be assigned to receive 30 hours of hypothermia with a target of 33 degrees followed by 24 hours of controlled rewarming.
|
Device: Therapeutic Hypothermia
Participants will receive therapeutic hypothermia for the assigned number of hours with controlled rewarming, using a closed-loop temperature control device. |
Experimental: 36 hours - shockable
Participants with shockable initial rhythm will be assigned to receive 36 hours of hypothermia with a target of 33 degrees followed by 24 hours of controlled rewarming.
|
Device: Therapeutic Hypothermia
Participants will receive therapeutic hypothermia for the assigned number of hours with controlled rewarming, using a closed-loop temperature control device. |
Experimental: 42 Hours - shockable
Participants with shockable initial rhythm will be assigned to receive 42 hours of hypothermia with a target of 33 degrees followed by 24 hours of controlled rewarming.
|
Device: Therapeutic Hypothermia
Participants will receive therapeutic hypothermia for the assigned number of hours with controlled rewarming, using a closed-loop temperature control device. |
Experimental: 48 hours - shockable
Participants with shockable initial rhythm will be assigned to receive 48 hours of hypothermia with a target of 33 degrees followed by 24 hours of controlled rewarming.
|
Device: Therapeutic Hypothermia
Participants will receive therapeutic hypothermia for the assigned number of hours with controlled rewarming, using a closed-loop temperature control device. |
Experimental: 60 hours - shockable
Participants with shockable initial rhythm will be assigned to receive 60 hours of hypothermia with a target of 33 degrees followed by 24 hours of controlled rewarming.
|
Device: Therapeutic Hypothermia
Participants will receive therapeutic hypothermia for the assigned number of hours with controlled rewarming, using a closed-loop temperature control device. |
Experimental: 72 hours - shockable
Participants with shockable initial rhythm will be assigned to receive 72 hours of hypothermia with a target of 33 degrees followed by 24 hours of controlled rewarming.
|
Device: Therapeutic Hypothermia
Participants will receive therapeutic hypothermia for the assigned number of hours with controlled rewarming, using a closed-loop temperature control device. |
Experimental: 6 hours - non shockable
Participants with non-shockable initial rhythm will be assigned to receive 6 hours of hypothermia with a target of 33 degrees followed by 6 hours of controlled rewarming.
|
Device: Therapeutic Hypothermia
Participants will receive therapeutic hypothermia for the assigned number of hours with controlled rewarming, using a closed-loop temperature control device. |
Experimental: 12 hours - non-shockable
Participants with non-shockable initial rhythm will be assigned to receive 12 hours of hypothermia with a target of 33 degrees followed by 12 hours of controlled rewarming.
|
Device: Therapeutic Hypothermia
Participants will receive therapeutic hypothermia for the assigned number of hours with controlled rewarming, using a closed-loop temperature control device. |
Experimental: 18 hours - non-shockable
Participants with non-shockable initial rhythm will be assigned to receive 18 hours of hypothermia with a target of 33 degrees followed by 18 hours of controlled rewarming.
|
Device: Therapeutic Hypothermia
Participants will receive therapeutic hypothermia for the assigned number of hours with controlled rewarming, using a closed-loop temperature control device. |
Experimental: 24 hour - non-shockable
Participants with non-shockable initial rhythm will be assigned to receive 24 hours of hypothermia with a target of 33 degrees followed by 24 hours of controlled rewarming.
|
Device: Therapeutic Hypothermia
Participants will receive therapeutic hypothermia for the assigned number of hours with controlled rewarming, using a closed-loop temperature control device. |
Experimental: 30 hours - non-shockable
Participants with non-shockable initial rhythm will be assigned to receive 30 hours of hypothermia with a target of 33 degrees followed by 24 hours of controlled rewarming.
|
Device: Therapeutic Hypothermia
Participants will receive therapeutic hypothermia for the assigned number of hours with controlled rewarming, using a closed-loop temperature control device. |
Experimental: 36 hours - non-shockable
Participants with non-shockable initial rhythm will be assigned to receive 36 hours of hypothermia with a target of 33 degrees followed by 24 hours of controlled rewarming.
|
Device: Therapeutic Hypothermia
Participants will receive therapeutic hypothermia for the assigned number of hours with controlled rewarming, using a closed-loop temperature control device. |
Experimental: 42 hours - non-shockable
Participants with non-shockable initial rhythm will be assigned to receive 42 hours of hypothermia with a target of 33 degrees followed by 24 hours of controlled rewarming.
|
Device: Therapeutic Hypothermia
Participants will receive therapeutic hypothermia for the assigned number of hours with controlled rewarming, using a closed-loop temperature control device. |
Experimental: 48 hours - non-shockable
Participants with non-shockable initial rhythm will be assigned to receive 48 hours of hypothermia with a target of 33 degrees followed by 24 hours of controlled rewarming.
|
Device: Therapeutic Hypothermia
Participants will receive therapeutic hypothermia for the assigned number of hours with controlled rewarming, using a closed-loop temperature control device. |
Experimental: 60 hours - non-shockable
Participants with non-shockable initial rhythm will be assigned to receive 60 hours of hypothermia with a target of 33 degrees followed by 24 hours of controlled rewarming.
|
Device: Therapeutic Hypothermia
Participants will receive therapeutic hypothermia for the assigned number of hours with controlled rewarming, using a closed-loop temperature control device. |
Experimental: 72 hours - non-shockable
Participants with non-shockable initial rhythm will be assigned to receive 72 hours of hypothermia with a target of 33 degrees followed by 24 hours of controlled rewarming.
|
Device: Therapeutic Hypothermia
Participants will receive therapeutic hypothermia for the assigned number of hours with controlled rewarming, using a closed-loop temperature control device. |
- Weighted Modified Rankin Scale (mRS) [ Time Frame: 90 days after return of spontaneous circulation ]The mRS is a 7 level ordinal scale of disability that ranges from 0 (no symptoms at all) to 6 (death). ICECAP uses weighting of mRS states to capture changes in functional status.
- All Cause Mortality [ Time Frame: 90 days after return of spontaneous circulation ]All patients who are dead at follow up.
- NIH Toolbox Crystallized Cognition Composite Score [ Time Frame: 90 days after return of spontaneous circulation ]Composite T-scores from a subset of study neuropsychological tests evaluating.
- NIH Toolbox Fluid Cognition Composite Score [ Time Frame: 90 days after return of spontaneous circulation ]Composite T-scores from a subset of study neuropsychological tests evaluating cognitive functioning in awake survivors collected on the NIH Toolbox platform. The fluid cognition composite score is more reflective of capacity for new learning and information. processing in novel situations
- Pneumonia [ Time Frame: 90 days after return of spontaneous circulation ]Determined by simplified Centers for Disease Control and Prevention (CDC) National Healthcare Safety Network (NHSN) definitions of Ventilator-Associated Event (VAE) or Pneumonia.
- Other infection [ Time Frame: 90 days after return of spontaneous circulation ]Determined by simplified CDC NHSN (Center for Disease Control National Healthcare Safety Network) definitions of Urinary Tract Infection or Blood Stream Infection.
- Malignant cardiac arrhythmia [ Time Frame: 90 days after return of spontaneous circulation ]Defined as any arrhythmia that requires termination with chest compressions, pacing, defibrillation, or electrical cardioversion. Arrhythmias (including atrial fibrillation) managed only with medication are excluded.
- Seizures [ Time Frame: 90 days after return of spontaneous circulation ]Defined as unambiguous convulsive or electroencephalographic seizure activity triggering urgent initial or additional anticonvulsant therapy. This definition does not include those given further anticonvulsants as secondary prophylaxis or as treatment for vague or uncertain exam findings or nondiagnostic electroencephalography. It does not include myoclonus.
- Neurological worsening [ Time Frame: 90 days after return of spontaneous circulation ]Determined by a decrease in Full Outline of Unresponsiveness (FOUR) score of ≥4 points that persists on two consecutive days or is associated with a neurological death. It excludes transient fluctuations in neurological examination or changes attributed to pharmacological sedation or paralysis.
- Electrolyte abnormalities [ Time Frame: 90 days after return of spontaneous circulation ]Defined as a measured serum Na, K, Mg, or Ca that is either higher or lower than study defined boundaries on at least two sequential measurements and resulting in a change in IV therapy. It excludes deliberate hypernatremia or hypermagnesemia induced to treat intracranial hypertension or shivering.
- Coagulopathies [ Time Frame: 90 days after return of spontaneous circulation ]Defined as requiring all 3 of the following parameters: (1) some form of major bleeding associated with (2) laboratory confirmation of an abnormal clotting axis and (3) treatment with blood product transfusion or reversal agent. Laboratory testing may include International Normalized Ratio (INR), partial thromboplastin time (PTT), clotting time, or thromboelastography.

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Ages Eligible for Study: | 18 Years and older (Adult, Older Adult) |
Sexes Eligible for Study: | All |
Accepts Healthy Volunteers: | No |
Inclusion Criteria:
- Coma after resuscitation from out of hospital cardiac arrest
- Cooled to <34 deg C with 240 minutes of cardiac arrest
- Definitive temperature control applied
- Age ≥ 18 years
- Informed consent from legal authorized representative (LAR) including intent to maintain life support for 96 hours
- Enrollment within 6 hours of initiation of cooling
Exclusion Criteria:
- Hemodynamic instability
- Pre-existing neurological disability or condition that confounds outcome determination
- Pre-existing terminal illness, unlikely to survive to outcome determination
- Planned early withdrawal of life support
- Presumed sepsis as etiology of arrest
- Prisoner

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT04217551
Contact: William Meurer | 734-232-2142 | wmeurer@med.umich.edu | |
Contact: Mickie Speers | 734-232-2142 | lraes@med.umich.edu |

Principal Investigator: | William Meurer | University of Michigan | |
Principal Investigator: | Robert Silbergleit | University of Michigan | |
Principal Investigator: | Romer Geocadin | Johns Hopkins University |
Documents provided by William J Meurer, University of Michigan:
Responsible Party: | William J Meurer, Associate Professor of Emergency Medicine and Neurology, University of Michigan |
ClinicalTrials.gov Identifier: | NCT04217551 |
Other Study ID Numbers: |
G160072 U01NS073476 ( U.S. NIH Grant/Contract ) |
First Posted: | January 3, 2020 Key Record Dates |
Last Update Posted: | May 9, 2023 |
Last Verified: | May 2023 |
Individual Participant Data (IPD) Sharing Statement: | |
Plan to Share IPD: | Yes |
Plan Description: | The data will be stored in the NHLBI data repository after trial completion. |
Supporting Materials: |
Study Protocol Statistical Analysis Plan (SAP) Informed Consent Form (ICF) |
Time Frame: | 1 year after publication on main outcome results paper |
Access Criteria: | Data use agreement with the appropriate NHLBI repository |
Studies a U.S. FDA-regulated Drug Product: | No |
Studies a U.S. FDA-regulated Device Product: | Yes |
Bayesian Adaptive Clinical Trial Hypothermia, therapeutic Coma |
Brain Ischemia Hypoxia-Ischemia, Brain Heart Arrest Out-of-Hospital Cardiac Arrest Ischemia Hypoxia Hypothermia Pathologic Processes Heart Diseases |
Cardiovascular Diseases Signs and Symptoms, Respiratory Body Temperature Changes Cerebrovascular Disorders Brain Diseases Central Nervous System Diseases Nervous System Diseases Vascular Diseases Hypoxia, Brain |