Even experts can have a hard time determining the degree of consciousness that patients have following severe cranio-cerebral injuries. A team of researchers at the University of Liège in Belgium have discovered a new method for determining gradual degrees of consciousness. The major advantage of this method is that it is suitable for everyday use. Nursing staff and families can utilise it. Prof Steven Laureys, one of the leading coma researchers and head of the Coma Science Group, presented the new approach in Barcelona at the 23rd Meeting of the European Neurological Society (ENS). About 3,000 experts are discussing current developments in this field at this congress.
Resistance means consciousness
Many people with consciousness disorders can be observed to resist having their eyes opened by someone else’s fingers. In their study, Prof Laureys’ team investigated whether resistance in coma patients is a reflex such as eyelids shutting if overstimulated or whether it is a sign of deliberate defence and thus an indication of consciousness. To this end, resistance to eye-opening was recorded for one week at a time in 108 patients over a period of 28 months. Corneal reflexes and furrowed brows were recorded for nearly all subjects in the study but only 22 were identified as exhibiting resistance to eye-opening (REO).
The Belgian researcher drew the following conclusion: “A significant finding was that most patients exhibiting resistance to eye-opening are in a persistent vegetative state or in a state of minimal consciousness. After repeated checks, it turned out that they had a higher level of consciousness than originally assumed. It is highly improbable that resistance to eye-opening is strictly a reflex mechanism. It seems much more likely to be a sign that a command is being carried out. If a patient displays resistance to eye-opening in more than half of the checks, there are good chances that he or she can follow certain commands.”
Repeated checks necessary
Prof Laureys calls for repeated assessments of individual patients, noting that the level of consciousness fluctuates in most patients. “They are not necessarily at their best when being examined. Test methods nursing staff can easily repeat in everyday care might change the assessment of many comatose people under certain circumstances. No small number of coma patients has a higher degree of consciousness than originally assumed. The classification is difficult to reverse once they have been diagnosed as being in a persistent vegetative state. At that point they enter long-term care and are examined by neurologists rarely if not at all.”
Prof Laureys said that the question as to what further things REO could indicate cannot be sufficiently answered from today’s perspective. He added: “With patients exhibiting this form of resistance one must urgently ask in any case whether they are receiving adequate therapy, including pain therapy, and whether they have been prematurely abandoned medically or are being emotionally neglected.” Resistance to eye-opening would be a simple observation criterion for family and nursing staff.
23rd Meeting of the European Society of Neurology (ENS) 2013.
ENS Abstract O267: Resistance to eye opening in patients with disorders of consciousness: reflex or voluntary?
European Neurological Society