Neuropsychological and neurological sequelae of out-of-hospital cardiac arrest and the estimated need for neurorehabilitation: a prospective pilot study.

Background: Diffuse brain injury is a key component of post-cardiac arrest syndrome reported in 30-80% of survivors of out-of-hospital cardiac arrest (OHCA). It is responsible for a high mortality rate, and is a common cause of cognitive and neurological deficits and disability. Symptom variability and dynamics and the rehabilitation potential remain poorly understood.

Aim: To investigate symptom prevalence, type, and severity and the natural course of recovery within 12 months after OHCA, and to estimate neurorehabilitation needs.

Methods: Study participants were selected from OHCA survivors admitted consecutively to a cardiac intensive care unit (CICU) serving 250,000 of Warsaw's inhabitants, according to the following inclusion criteria: first ever nontraumatic, normothermic cardiac arrest, age ≤ 75 years; cardiology ward survival until discharge, and no history of pre-existing brain disease. Patients' cognitive and neurological status and disability were evaluated in the first days after onset and three, six and 12 months later. Neuropsychological assessment focused on attention, memory, executive, linguistic and visuo-spatial abilities. Neurological examination included assessment of cranial nerves, muscle strength and tone, deep tendon reflexes, cerebellar function, sensory function, and gait. The general psychophysical state was classified using the Disability Rating Scale. Patients' neurorehabilitation needs were determined using data collected three months post-OHCA. This data was used to estimate future demands for such resources in Poland.

Results: During a 28-month study period, of 69 OHCA patients admitted to the CICU, 29 met the study criteria (33 survived until discharge from cardiology unit; four did not meet further criteria). Severe consciousness disorders were most frequent in the early post-OHCA phase (28%); no unresponsive patients were identified 12 months later. Of responsive patients who were capable of at least minimal co-operation, 100% (early after OHCA) to 57% (12 months after OHCA) had cognitive impairment, usually with neurological symptoms. Memory impairment was the most common and severe problem, followed by executive, attentional, language and visuo-spatial dysfunctions. The prevalence of neurological deficits ranged from 88% (early after OHCA) to 43% (12 months after OHCA). Due to acquired deficits, between 71% (early post-OHCA) and 36% (12 months post-OHCA) of patients were significantly disabled and often dependent. Although dysfunctions tended to improve, over 50% of the patients remained impaired 12 months post-OHCA, and over 30% were significantly disabled. We estimated that about 800 OHCA survivors/year in Poland will develop symptoms requiring neurorehabilitation.

Conclusions: Cognitive and neurological symptoms are common after cardiac arrest brain injury. Establishing specialised neurorehabilitation centres is essential for treating these patients.