Reoxygenation After Cardiac Arrest II (REOX II Study)
Condition: Cardiac Arrest
MeSH terms: Heart Arrest
Intervention: Protocol for rapid FiO2 optimization
Intervention description: We plan to test a protocol for FiO2 optimization for mechanically ventilated post-cardiac arrest subjects, with a therapeutic goal of partial pressure of arterial oxygen (PaO2) of 60-99 mmHg, based on the PaO2 range that was associated with the lowest risk of poor outcome in our previously published work. We also use PaO2 (measured by arterial blood gas [ABG] analysis) as the ultimate goal rather than arterial oxygen saturation (SaO2) measured by pulse oximetry because an SaO2 value <100% on pulse oximetry monitoring does not always exclude supranormal PaO2. The protocol in this application begins with very rapid reduction of FiO2 as much as possible according to SaO2 values, and when FiO2 is maximally reduced by SaO2 an ABG is measured, followed by finer adjustment of FiO2 to achieve a PaO2 60-99 mmHg. The protocol not only prescribes each downward titration of FiO2 but it also includes detailed limbs for upward titration of FiO2 to account for potential "overshoot" in FiO2 reduction.
Phase: Phase 1
Study type: Interventional
Primary purpose: Treatment
Intervention model: Single Group Assignment
Masking: None (Open Label)
Enrollment: 16.0
Sex: All
Minimum age: 18 Years
Healthy volunteers: No
Keywords: Cardiac Arrest, Hyperoxia, Ischemia-reperfusion Injury, Reactive Oxygen Species, Oxidative Stress, Neuropsychological Tests

Summary:

      The broad objective of this study is to test the association between hyperoxia exposure after
      resuscitation from cardiac arrest and outcome. After obtaining written informed consent
      subjects enrolled in REOX II will undergo a rapid faction of inspired oxygen (FiO2)
      optimization protocol to prevent exposure to hyperoxia. We will compare outcomes between
      subjects enrolled in REOX I (observational study only) and REOX II (intervention: rapid FiO2
      optimization protocol). Our overarching hypothesis is that exposure to hyperoxia after return
      of spontaneous circulation (ROSC) is associated with increased oxidative stress and worsened
      neurological and cognitive outcomes.
    

Eligibility criteria:

        Inclusion Criteria:

          -  Age >17 years

          -  Cardiac arrest

          -  Return of spontaneous circulation

          -  Not following commands immediately after ROSC

          -  Endotracheal intubation

          -  Clinician intent to treat with therapeutic hypothermia (or absence of clinician intent
             to withhold therapeutic hypothermia)

        Exclusion Criteria:

          -  Presumed etiology of arrest is trauma

          -  Presumed etiology of arrest is hemorrhage

          -  Presumed etiology of arrest is sepsis

          -  Permanent resident of nursing home or other long-term care facility

          -  Any other condition, that in the opinion of the investigator, would preclude the
             subject from being a suitable candidate, e.g. end stage chronic illness with no
             reasonable expectation of survival to hospital discharge