Unexpected fatal neurological deterioration after successful cardio-pulmonary resuscitation and therapeutic hypothermia.

A 77-year-old woman was admitted to the intensive care unit after successful cardiopulmonary resuscitation for out-of-hospital cardiac arrest due to pulseless electrical activity. She was treated with mild therapeutic hypothermia to minimise secondary anoxic brain damage. After a 24 h period of therapeutic hypothermia with a temperature of 32.5 degrees C, the patient was rewarmed and sedation discontinued. Neurological evaluation after 24 h revealed a maximum Glasgow Coma Score of E4M4Vt with spontaneous breathing. However the patient developed a fever reaching 39 degrees C for several hours that was unresponsive to conventional cooling methods. In the subsequent 24 h patient developed apnoea, hypotension and bradycardia with deterioration of the coma score. Diabetes insipidus was confirmed. Cerebral CT was performed which showed diffuse brain oedema with herniation and brainstem compression. The patient died within hours. Autopsy showed massive brain swelling and tentorial herniation. Hyperthermia possibly played a pivotal role in the development of this fatal insult to this vulnerable brain after cardiac arrest and therapeutic hypothermia treatment. The acute histopathological alterations in the brain, possibly caused by the deleterious effects of fever after cardiac arrest in human brain, may be considered a new observation.