fMRI in CardiaC arrEst With Uncertain Prognosis

Our goal here is to determine whether advanced functional MRI and DTI sequences add actionable prognostic information relative to standard clinical MRI in patients who remain comatose after cardiac arrest. We plan the following specific analyses:

Aim 1: We will use logistic regression to measure the association between our primary outcome and fMRI BOLD response to (a) passive language stimuli, (b) motor imagery or (c) passive sensory stimuli, in a model with age, Glasgow Coma Scale (GCS) score at time of MRI, and presence of anoxic injury on clinical diffusion weighted MRI.

Aim 2: We will use logistic regression to measure the association between our primary outcome and default mode network resting state functional connectivity, in a model with age, Glasgow Coma Scale (GCS) score at time of MRI, and presence of anoxic injury on clinical diffusion weighted MRI.

Aim 3: We will use logistic regression to measure the association between our primary outcome and diffusion tensor imaging (DTI)-measured mean white matter fractional anisotropy, in a model with age, Glasgow Coma Scale (GCS) score at time of MRI, and presence of anoxic injury on clinical diffusion weighted MRI.

Inclusion criteria

• survive of an in or out of hospital cardiac arrest

Exclusion criteria

• Drug overdose
• Opinion of medical team patient unlikely to survive more than 24 hours (severe concurrent medical illness, dilated and unreactive pupils, etc..)
• Following verbal commands (MD or RN note) once TTM is complete and normothermia is achieved (Day 2 or 3; Day of admission is Hospital Day 0). If no TTM is administered, this can be assessed on Hospital Day 2.
• Following verbal commands (study team assessment) at time of MRI
• Family planning to WLST at time of enrollment
• Non English speaker (okay if English not primary language, as long as they can understand it)
• Permanent Contraindication to MRI (some kind of implanted metal)
• Pregnant