Assessing Cognitive Outcomes in Coma Survivors: A Literature Review

Allison Frantz; Natalia Incio Serra; Aracely Lopez Almendariz; Catherine Duclos; Adrian M Owen; Stefanie Blain-Moraes

doi:10.3390/brainsci13010096

Assessing Cognitive Outcomes in Coma Survivors: A Literature Review

Brain Sci. 2023 Jan 4;13(1):96. doi: 10.3390/brainsci13010096.

Authors

Allison Frantz^{1

2}, Natalia Incio Serra¹, Aracely Lopez Almendariz³, Catherine Duclos^{4

5}, Adrian M Owen⁶, Stefanie Blain-Moraes²

Affiliations

¹ Montreal General Hospital, Research Institute of the McGill University Health Center, Montreal, QC H3G 1A4, Canada.
² Integrated Program in Neuroscience, Faculty of Medicine, McGill University, Montreal, QC H3A 1A1, Canada.
³ School of Physical and Occupational Therapy, Faculty of Medicine, McGill University, Montreal, QC H3G 1Y5, Canada.
⁴ Department of Anesthesiology and Pain Medicine, Université de Montréal, Montreal, QC H3C 3J7, Canada.
⁵ Hôpital du Sacré-Coeur de Montréal, Centre Intégré Universitaire de Santé de Services Sociaux du Nord-de-l'île-de-Montréal, Montreal, QC H3C 3J7, Canada.
⁶ Department of Physiology and Pharmacology and Department of Psychology, University of Western Ontario, London, ON N6A 5C2, Canada.

Abstract

(1) Background: Although cognitive impairments in coma survivors are common, methods of measuring long-term cognitive outcomes in this population are inconsistent, precluding the development of a strong evidence-base to support clinical decision making. In this literature review, we identify and characterize the measures used to track cognitive recovery in coma survivors to data. (2) Methods: We extracted the instrument used for cognitive assessment, the cognitive domains assessed, methods administration and scoring, and timing of assessment from 134 of 996 screened records. (3) Results: A total of 133 unique cognitive tests and cognitive testing batteries were identified, with 97 cognitive instruments used in less than three articles. The instruments assessed 20 different cognitive domains, with 73 articles also using tests that assess general "cognitive ability". Cognitive instruments ranged from subjective assessments to comprehensive cognitive batteries. There were inconsistent points of reference for the timing of assessment across studies, with few studies repeating assessments at more than one time point, and arbitrary time intervals between tests. (4) Conclusions: Overall, this review illustrates the enormous disparity between studies that track cognitive outcome in coma survivors, and the need for a systematic, patient-accessible method of assessing cognitive functioning in future studies with this population.

Keywords: brain injury; cognitive assessment; cognitive instrument; cognitive outcome; coma; critical care; intensive care; unconsciousness.

Publication types

Review

Grants and funding

This study was funded through the Healthy Brains for Healthy Lives and BrainsCAN McGill-Western Collaboration Grant Program (Grant ID: 1a-5a-01). SBM is supported by the Canada Research Chairs Program (Tier II) and the Natural Sciences and Engineering Research Council of Canada (RGPIN-2016-03817). CD is supported by a Postdoctoral Fellowship from the Canadian Institutes of Health Research (CIHR) (FRN 152564). AMO is supported by the Canadian Institutes of Health Research (CIHR, #408004), and the Natural Sciences and Engineering Research Council of Canada (RGPIN-2018-05878). AMO also receives support from the CIFAR Brain, Mind, and Consciousness Program.