Recovery among post-arrest patients with mild-to-moderate cerebral edema.

BACKGROUND: Cerebral edema after cardiac arrest may be a modifiable cause of secondary brain injury. We aimed to identify processes of care associated with recovery in a cohort of patients with mild to moderate edema. METHODS: We conducted a retrospective cohort study of adults resuscitated from out-of-hospital arrest (OHCA) at a single center from 2010 to 2018. We included those with cerebral edema ranging from mild to moderate (gray to white matter attenuation ratio (GWR) 1.2 to 1.3 on initial brain computerized tomography (CT). We used Pittsburgh Cardiac Arrest Category (PCAC) to adjust for illness severity and considered the following values in the first 24 h of admission as additional predictors: GWR, lab values affecting serum osmolality (sodium, glucose, blood urea nitrogen (BUN)), total osmolality, change in osmolality from 0 to 24 h, cardiac etiology of arrest, targeted temperature to 33 °C (vs 36 °C), time-weighted mean arterial pressure (MAP), partial pressures of arterial oxygen and carbon dioxide and select medications. Our primary outcome was discharge with cerebral performance category 1-3. We used unadjusted and adjusted logistic regression for analysis. RESULTS: We included 214 patients for whom CT was performed median 3.8 [IQR 2.4-5.2] hours after collapse. Median age was 57 [IQR 48-67] years, 82 (38%) were female, and 68 (32%) arrested from ventricular tachycardia or fibrillation. In adjusted models, modifiable processes of care were not associated with outcome. CONCLUSIONS: Illness severity, but not modifiable processes of care, were associated with recovery among post-arrest patients with mild-to-moderate cerebral edema.

Duration and clinical features of cardiac arrest predict early severe cerebral edema.

BACKGROUND: Severe brain edema appears early after cardiopulmonary resuscitation (CPR) in a subset of patients and portends a poor prognosis. We tested whether clinical features of patients or resuscitation during out-of-hospital cardiac arrest (OHCA) are associated with early, severe cerebral edema. METHOD/RESEARCH DESIGN: We reviewed pre-hospital and hospital records for comatose patients surviving to hospital admission after OHCA who had computed tomography (CT) of brain at the time of hospital admission available for inspection. We measured the gray-white ratio (GWR) of X-ray attenuation between the caudate nucleus and posterior limb of the internal capsule, defining severe cerebral edema as GWR < 1.20. We calculated associations between severe cerebral edema and patient or resuscitation variables. RESULTS: Between 2010 and 2019, 1340 subjects were admitted of whom 296 (22%) showed severe cerebral edema on initial CT. Subjects with severe edema had lower survival (5/296, 2% vs. 377/1044, 36%). Severe edema was independently associated with total CPR duration, total dose of epinephrine, younger age, non-shockable arrest rhythms, fewer total number of rescue shocks, rearrest after initial return of pulses, and non-cardiac arrest etiology. Prevalence of severe cerebral edema increased from 2% among subjects with 0-10 min of CPR to 31% among subjects with >40 min of CPR. CONCLUSION: CPR duration along with easily measurable clinical and resuscitation characteristics predict early severe cerebral edema after OHCA. Future interventional trials should consider targeting or preventing cerebral edema after prolonged hypoxic-ischemic brain injury especially in patients with high risk clinical features.