THE MINIMALLY CONSCIOUS STATE IN CHILDREN

Abstract

The minimally conscious state is a disorder of minimal but clearly discernible behavioral evidence of self or environmental awareness. MCS can occur in children with acute brain injuries, progressive neurometabolic disorders or nervous system malformations. MCS must be distinguished from the VS because the evaluation, care, medical decision-making and prognosis differs. It is assumed that the lower limit of MCS occurs when patients emerge from the VS and show evidence of awareness. It will be necessary to develop good bedside methods that are valid, reliable and easy to use so that those caring for such patients can employ them in a timely manner. Likewise, it will be necessary to define the upper limits of this condition. The term minimally conscious be restrictive so that it is clear that such patients do not have the ability to express preferences, use judgment or are capable of expressing choices about their care options or other quality of life issues. Clinicians will need to continue to relay on bedside clinical testing but recent advances in neuroimaging such as PET scanning may provide more objective methods to assess consciousness. Such testing will first be developed for adults; validating such technologies for pediatric use will be necessary. Until then, developing and validating clinical batteries of standardized tests in different age populations will be required. While it is unknown if and to what extent patients can emerge from MCS after 12 months post-injury, it appears that the majority of persons in MCS for 12 months remain severely disabled. Special care must be taken when evaluating infants and children under the age of three years who have sustained severe brain injury. In this age group, assessment of cognitive function is constrained by immature language and motor development. This limits the degree to which command-following, verbal expression and purposeful movement can be relied upon to determine whether the diagnostic criteria for MCS have been met Additional research concerning prognosis, long-term outcome and treatment effectiveness will be needed to help clarify many of the medical, ethical and legal issues surrounding the care of such patients.