Delayed postanoxic encephalopathy: a case report and literature review.

Delayed postanoxic encephalopathy is a rare condition in which patients appear to make a complete clinical recovery after an episode of anoxia or hypoxia but then develop a relapse characterized by apathy, confusion, agitation, and/or progressive neurologic deficits. The incidence of delayed postanoxic encephalopathy is unclear but has been reported to range from less than 1 to 28 per 1000 in patients who have suffered hypoxic or anoxic events. The exact pathogenesis remains unknown. We describe a case of an independently living 51-year-old woman admitted to an inpatient rehabilitation unit 11 days after a respiratory arrest. At admission, she exhibited cognitive and visual deficits that were relatively mild but prevented a safe return to independent living. Two days later, she developed the sudden onset and rapid worsening of parkinsonian symptoms and excruciating bilateral lower-extremity pain. The pain was intractable, and over the next 2 days she progressed to being unable to walk or perform her activities of daily living without maximum assistance. A diagnosis of delayed postanoxic encephalopathy was made, and the patient responded to a trial of carbidopa and levodopa as well as redirection of her physical and occupational therapy programs. This case illustrates the unusual presentation of delayed postanoxic encephalopathy during inpatient rehabilitation and suggests that this condition should be considered if patients who have suffered an anoxic or hypoxic event show a sudden neurologic deterioration.