Clinical paperLong-term neurological outcomes in out-of-hospital cardiac arrest patients treated with targeted-temperature management☆
Introduction
Hypoxic-ischemic brain injury encompasses a whole spectrum of lesions after out-of-hospital cardiac arrest (OHCA) [1]. In order to improve the neurological prognosis of OHCA patients, clinical guidelines recommend the use of targeted temperature management (TTM) after return of spontaneous circulation (ROSC) [2].
Ultimate assessment of neurological and functional outcomes in OHCA patients is usually based on simple scales, such as CPC or modified Rankin scale (mRS), which are not able to discriminate situations of mild or moderate cognitive impairment [3,4]. Therefore, these prognostic tools dichotomize the overall result of a given patient into two large groups: those who have suffered very serious sequelae and those who have not [5].
Few studies have focused on cognitive and functional outcomes of OHCA survivors, and clinical data are especially lacking of long-term prognosis information [6,7] even though some studies suggest that there may be a slowly progressive improvement after hospital discharge [[7], [8], [9]].
This study aimed to assess long-term cognitive and functional outcomes in OHCA patients treated with TTM surviving at least one year after the index event. The secondary objective was to investigate the relationship between these long-term outcomes and baseline characteristics, in order to identify the existence of prognostic factors that could be assessed during initial admission.
Section snippets
Patients
Patients admitted to the Coronary Unit due to OHCA with a Glasgow Coma Scale ≤8 after ROSC, from August 2007 to November 2015 and surviving at least one year after cardiac arrest were included. All patients received TTM according to the current protocol in our center. The targeted temperature (32–34 °C) was either selected at discretion of the treating physician or assigned by randomization as part of a clinical trial [10,11]. Those with a score equal to or greater than 3 in the CPC scale prior
Patients and baseline characteristics
During the study period, a total of 124 patients admitted after OHCA and surviving at least 1 year after the event, were identified. Finally, 79 patients were included in the study after being assessed through the corresponding structured interview (Flow chart is shown in Ref. [17]). The median follow-up time was 3.1 years (interquartile range 1.7–4.4 years). No significant correlations were observed between the quantitative results of cognitive assessment tests and this follow-up time.
The
Discussion
Mortality after OHCA remains very high, with a survival rate at hospital discharge of 11.4% [21]. Even among those patients who achieve ROSC, in-hospital mortality ranges from 20% to 50% depending on the study population (i.e. rate of bystander cardiopulmonary resuscitation, use of automated external defibrillators) [22,23], being hypoxic-ischemic brain injury the leading cause of death [24,25]. Post-cardiac arrest care includes a combination of strategies, including TTM, aimed to assess and
Conclusions
There is a high prevalence of long-term cognitive deficits in OHCA survivors. Even in a selected population, more than half of the patients experienced some degree of cognitive impairment, in addition to other functional and psychosocial limitations.
The cognitive scales most commonly used in clinical practice to assess the neurological outcomes after cardiac arrest (CPC and mRS) are crude and lack sensitivity to detect most of these deficits, occasionally subtle and difficult to appreciate on
Conflicts of interests
All the authors wish to confirm that there are no known conflicts of interest associated with this publication and there has been no significant financial support for this work that could have influenced its outcome.
Acknowledgment
The authors thank Jesús Díez Sebastían M.D. Ph.D., from the Biostatistics Department at Hospital Universitario La Paz, for assistance with statistical analysis.
References (37)
- et al.
Assessment of outcome after severe brain damage
Lancet
(1975) - et al.
Early neurologically-focused follow-up after cardiac arrest improves quality of life at one year: a randomised controlled trial
Int J Cardiol
(2015) - et al.
Cardiac arrest and hypothermia treatment-function and life satisfaction among survivors in the first 6 months
Resuscitation
(2014) Trail making test A and B: normative data stratified by age and education
Arch Clin Neuropsychol
(2004)- et al.
Estudios normativos españoles en población adulta joven (Proyecto NEURONORMA jóvenes): normas para las pruebas span verbal, span visuoespacial, letter-number sequencing, trail making test y symbol digit modalities test
Neurologia
(2012) - et al.
The influence of induced hypothermia and delayed prognostication on the mode of death after cardiac arrest
Resuscitation
(2013) - et al.
Quality-of-life and formal functional testing of survivors of out-of-hospital cardiac arrest correlates poorly with traditional neurologic outcome scales
Ann Emerg Med
(1996) - et al.
Association between cerebral performance category, modified Rankin Scale, and discharge disposition after cardiac arrest
Resuscitation
(2011) - et al.
Determinants of cognitive outcome in survivors of out-of-hospital cardiac arrest
Resuscitation
(2014) - et al.
Ischaemic brain damage after cardiac arrest and induced hypothermia-a systematic description of selective eosinophilic neuronal death. A neuropathologic study of 23 patients
Resuscitation
(2014)
Anxiety and depression among out-of-hospital cardiac arrest survivors
Resuscitation
Clinical pathophysiology of hypoxic ischemic brain injury after cardiac arrest: a “two-hit” model
Crit Care
Part 8: post-cardiac arrest care: 2015 American Heart Association guidelines update for cardiopulmonary resuscitation and emergency cardiovascular care
Circulation
The United Kingdom transient ischaemic attack (UK-TIA) aspirin trial: final results
J Neurol Neurosurg Psychiatry
Neurological prognostication after cardiac arrest
Curr Opin Crit Care
Surviving out-of-hospital cardiac arrest: the neurological and functional outcome and health-related quality of life one year later
Resuscitation
A neuropsychological and neurological sequelae of out-of-hospital cardiac arrest and the estimated need for neurorehabilitation: a prospective pilot study
Kardiol Pol
Hypothermia in comatose survivors from out-of-hospital cardiac arrest: pilot trial comparing 2 levels of target temperature
Circulation
Cited by (0)
- ☆
A Spanish translated version of the abstract of this article appears as Appendix in the final online version at https://doi.org/10.1016/j.resuscitation.2018.09.015.
- 1
These authors contributed equally to this paper.