Long-term neurological outcomes in out-of-hospital cardiac arrest patients treated with targeted-temperature management

Abstract

Background: This study aimed to assess long-term cognitive and functional outcomes in out-of-hospital cardiac arrest (OHCA) patients treated with targeted-temperature management, investigate the existence of prognostic factors that could be assessed during initial admission and evaluate the usefulness of classic neurological scales in this clinical scenario.

Methods: Patients admitted due to OHCA from August 2007 to November 2015 and surviving at least one year were included. Each patient completed a structured interview focused on the collection of clinical, social and demographic data. All available information in clinical records was reviewed and a battery of neurocognitive and psychometric tests was performed.

Results: Seventy-nine patients were finally included in the analysis. Forty-three patients (54.4%) scored below the usual cut-off points for the diagnosis of mild cognitive impairment, even though most of these deficits went unnoticed when patients were assessed using CPC and modified Rankin scale. Nineteen (24%) developed certain degree of impairment in their attention capacity and executive functions. A significant proportion developed new memory-related disorders (43%), depressive symptoms (17.7%), aggressive/uninhibited behavior (12.7%) and emotional lability (8.9%). A greater number of weekly hours of intellectual activity and a qualified job were independent protective factors for the development of cognitive impairment. However, being older at the time of the cardiac arrest was identified as a poor prognostic factor.

Conclusions: There is a high prevalence of long-term cognitive deficits and functional limitations in OHCA survivors. Most commonly used clinical scales in clinical practice are crude and lack sensitivity to detect most of these deficits.

Keywords: Cardiac arrest; Cognitive scales; Hypoxic ischemic brain injury; Long-term outcomes; Targeted-temperature management.