Isolation Syndrome after Cardiac Arrest and Therapeutic Hypothermia.

TitleIsolation Syndrome after Cardiac Arrest and Therapeutic Hypothermia.
Publication TypeJournal Article
Year of Publication2016
AuthorsForgacs PB, Fridman EA, Goldfine AM, Schiff ND
JournalFront Neurosci
Volume10
Pagination259
Date Published2016
ISSN1662-4548
Abstract

Here, we present the first description of an isolation syndrome in a patient who suffered prolonged cardiac arrest and underwent a standard therapeutic hypothermia protocol. Two years after the arrest, the patient demonstrated no motor responses to commands, communication capabilities, or visual tracking at the bedside. However, resting neuronal metabolism and electrical activity across the entire anterior forebrain was found to be normal despite severe structural injuries to primary motor, parietal, and occipital cortices. In addition, using quantitative electroencephalography, the patient showed evidence for willful modulation of brain activity in response to auditory commands revealing covert conscious awareness. A possible explanation for this striking dissociation in this patient is that altered neuronal recovery patterns following therapeutic hypothermia may lead to a disproportionate preservation of anterior forebrain cortico-thalamic circuits even in the setting of severe hypoxic injury to other brain areas. Compared to recent reports of other severely brain-injured subjects with such dissociation of clinically observable (overt) and covert behaviors, we propose that this case represents a potentially generalizable mechanism producing an isolation syndrome of blindness, motor paralysis, and retained cognition as a sequela of cardiac arrest and therapeutic hypothermia. Our findings further support that highly-preserved anterior cortico-thalamic integrity is associated with the presence of conscious awareness independent from the degree of injury to other brain areas.

DOI10.3389/fnins.2016.00259
Alternate JournalFront Neurosci
PubMed ID27375420
PubMed Central IDPMC4899438
Grant ListK23 NS096222 / NS / NINDS NIH HHS / United States
UL1 TR000043 / TR / NCATS NIH HHS / United States
K23 HD079556 / HD / NICHD NIH HHS / United States
R01 HD051912 / HD / NICHD NIH HHS / United States
UL1 TR000457 / TR / NCATS NIH HHS / United States