Coma Near-Coma Research Articles

Psychometric Properties of the Coma Near-Coma Scale for Adults in Disordered States of Consciousness: A Rasch Analysis

ObjectivesTo examine the construct validity and measurement precision of the Coma Near-Coma scale (CNC) in measuring neurobehavioral function (NBF) in patients with disorders of consciousness receiving postacute care rehabilitation. DesignRasch analysis of retrospective data. ParticipantsParticipants (N=48) with disordered consciousness who were admitted to postacute care rehabilitation. InterventionsNot applicable. Main Outcome MeasureCNC. ResultsAssessment with CNC repeated weekly until the participant was conscious or discharged from the postacute care facility (451 participant records). Rating scale steps were ordered for all items. Eight of the 10 CNC items evaluated in this study fit the measurement model (χ2=5332.58; df=11; P=.17); pain items formed a distinct construct. The ordering of the 8 items from most to least challenging makes clinical sense and compares favorably with other published hierarchies of NBF. Tactile items are more easily responded to. Visual and auditory items requiring higher cognitive processing were more challenging. In the full sample, the CNC achieved good measurement precision, with a person separation reliability of 0.87. ConclusionsThe items of the CNC reflect good construct validity and acceptable interrater reliability. The measurement precision achieved indicates that the CNC may be used to make decisions about groups of individuals but that these items may not be sufficiently precise for individual patient treatment decision-making.

Evaluating the validity, reliability and clinical utility of the Music therapy Sensory Instrument for Cognition, Consciousness and Awareness (MuSICCA): protocol of a validation study

IntroductionA growing number of children and young people are surviving severe acquired brain injuries due to advances in healthcare. However, many fail to emerge from coma and continue to live...

The Coma-Near Coma Scale: An Examination of the Psychometric Properties Using Rasch Analysis

To examine the construct validity and measurement precision of the Coma-Near Coma Scale (CNC) in measuring neurobehavioral functioning (NBF) in patients with disorders of consciousness receiving post-acute rehabilitation.

Placebo-Controlled Trial of Familiar Auditory Sensory Training for Acute Severe Traumatic Brain Injury

Background. Sensory stimulation is often provided to persons incurring severe traumatic brain injury (TBI), but therapeutic effects are unclear. Objective. This preliminary study investigated neurobehavioral and neurophysiological effects related to sensory stimulation on global neurobehavioral functioning, arousal, and awareness. Methods. A double-blind randomized placebo-controlled trial where 15 participants in states of disordered consciousness (DOC), an average of 70 days after TBI, were provided either the Familiar Auditory Sensory Training (FAST) or Placebo of silence. Global neurobehavioral functioning was measured with the Disorders of Consciousness Scale (DOCS). Arousal and awareness were measured with the Coma-Near-Coma (CNC) scale. Neurophysiological effect was measured using functional magnetic resonance imaging (fMRI). Results. FAST (n = 8) and Placebo (n = 7) groups each showed neurobehavioral improvement. Mean DOCS change (FAST = 13.5, SD = 8.2; Placebo = 18.9, SD = 15.6) was not different, but FAST patients had significantly (P = .049; 95% confidence interval [CI] = −1.51, −.005) more CNC gains (FAST = 1.01, SD = 0.60; Placebo = 0.25, SD = 0.70). Mixed-effects models confirm CNC findings (P = .002). Treatment effect, based on CNC, is large (d = 1.88, 95% CI = 0.77, 3.00). Number needed to treat is 2. FAST patients had more fMRI activation in language regions and whole brain (P values <.05) resembling healthy controls’ activation. Conclusions. For persons with DOC 29 to 170 days after TBI, FAST resulted in CNC gains and increased neural responsivity to vocal stimuli in language regions. Clinicians should consider providing the FAST to support patient engagement in neurorehabilitation.

Continuous subcutaneous apomorphine for severe disorders of consciousness after traumatic brain injury

Background: The prognosis of long-term severe disorders of consciousness due to traumatic brain injury is discouraging. There is little definitive evidence of the underlying mechanisms, but a deficiency of the dopaminergic system may be involved.Methods: In a prospective open-labelled clinical study, the feasibility, relative efficacy and safety of continuous subcutaneous (s.c.) administration of apomorphine in Vegetative State (VS) or Minimally Conscious State (MCS) patients due to severe traumatic brain injury (TBI) was tested. Apomorphine was administered to eight patients. Outcome measures were the Coma Near-Coma Scale (CNCS) and Disability Rating Scale (DRS).Results: Drug management was implemented without any problems. There was improvement in the primary outcomes for all patients. Awakening was seen as rapidly as within the first 24 hours of drug administration and as late as 4 weeks. Seven of the patients had completely recovered consciousness. All improvements were sustained for at least 1 year, even after apomorphine was discontinued. Drug-related adverse events were all anticipated and resolved after the dose was reduced.Conclusion: Based on this open-label pilot study, continuous s.c. apomorphine infusion appears to be feasible, safe and potentially effective in improving consciousness in patients in VS and MCS due to severe TBI.

A comparison of a behavioural assessment tool and electrophysiological measures of recovery from coma

The Wessex Head Injury Matrix (WHIM) [1] is one of the rare behavioural scales that have been designed to follow the recovery of head-injured patients throughout the whole spectrum of altered states of consciousness, from exit of coma to complete recovery. In this study, we explored the validity of the WHIM in relation to other behavioural assessment tools – Glasgow–Liege Coma Scale (GLS) [2], Coma-Near Coma scale (CNC) [3], Western Neuro Sensory Stimulation Profile (WNSSP) [4] – as well as in relation to the Bi-Spectral Index (BIS), derived from electroencephalographic measures. Twenty-nine brain-injured comatose patients (aged 21–83 years) were followed longitudinally with these behavioural and electrophysiological measures. Overall, the evolution of the scores on the WHIM correlated significantly with the evolution of scores obtained by the GLS (r = 0.88; P < 0.01), the CNC (r = -0.8; P < 0.01), the WNSSP (r = 0.87; P < 0.01), as well as with the BIS measure (r = 0.58; P < 0.01). Relative to the GLS, CNC and WNSSP, the WHIM showed a particularly good sensitivity for documenting subtle changes in recovery for patients in a minimally conscious state. The BIS index globally evolved in parallel to the behavioural scales. However, it showed a very bad sensitivity as many patients in a coma or a vegetative state presented BIS scores that were as high as those observed for patients that had regained normal consciousness. The results confirm the usefulness of the WHIM, especially for the assessment of minimally conscious patients. However, even if a global relation is observed with behavioural scales, the validity of electrophysiological measures such as the BIS index is unsatisfactory for the assessment of altered states of consciousness.

Poster 131: Evaluation of anoxic brain injuries in children using the coma/near coma scale.

Objective: To evaluate the role that admission coma level plays in predicting recovery from coma secondary to anoxic brain injury. Design: Retrospective cohort review of pediatric anoxic brain injuries. Setting: Inpatient neurotrauma rehabilitation care unit. Participants: 13 patients identified on admission with a diagnosis of anoxic brain injury and in a state of “moderate” to “extreme” coma, as determined by evaluation using the Coma/Near Coma (CNC) Scale. Interventions: Not applicable. Main Outcome Measure: CNC score. Scoring system rates level of coma on a scale ranging from 4 (extreme) to 0 (no coma). Results: Patients in coma with a diagnosis of anoxic brain injury of varying etiology were scored on admission and at discharge. A discussion of extent of recovery between admission and discharge and how this relates to various parameters is presented. All 13 patients were in a state of moderate to extreme coma (CNC score, >2.01), with 70% (n=9) in the marked to extreme coma range (CNC score, >2.9). Regardless of their initial score, 46% (n=5) improved to a state of near to no coma (CNC score, <2). Of the 13 patients reviewed, 23% (n=3) made no improvements at all. Conclusions: In this small cohort, level of coma on admission was not predictive of recovery from a comatose state. A high percentage (46%) of these children were discharged in a state of near to no coma, independent of admission coma level. This does not suggest, however, that recovery from coma is predictive of long-term cognitive and motor recovery. Assessment of long-term outcomes to further evaluate the capacity for recovery from anoxic brain injury is indicated.

Motor profile of patients in minimally responsive and persistent vegetative states

The purpose of this descriptive clinical study is to document the motor characteristics of patients in minimally responsive and persistent vegetative states. Twelve subjects, presenting a prolonged altered state of consciousness (x = 7.82 years, range 2-27), aged 27-78 years (x = 50, SD = 15.26) were evaluated, using standardized protocols, on the following variables: passive range of motion, observed movements, reflexes, tonus, postural status and reactions. The subjects' level of awareness and responsivity were measured with the Coma/Near Coma (CNC) scale at each of the three data collection sessions. While group CNC scores were stable over the three sessions, fluctuations in the level of awareness of individual subjects was recorded, confirming the heterogeneity of this clientele. Abnormal primitive reflexes were present in all subjects, with the flexor withdrawal (75%), the tonic labyrinthine (36%) and the body-on-body righting reaction (25%) being the most frequently observed. All subjects presented altered tonus, considerable posturing and varied degrees of reduced range of joint motion. A range of abnormal (e.g. chewing, clonus) and normal patterned (e.g. bridging, scratching) movement behaviours was recorded, but these did not translate into functional use, such as rolling. Collectively, the findings stress the complexity of the motor profile of patients in minimally responsive and vegetative states, and suggest the need for physiotherapists to become more actively involved in the evaluation and treatment of this clientele.

Evaluation of coma and vegetative states.

The Coma/Near-Coma (CNC) scale was designed to measure small clinical changes in patients with severe traumatic and nontraumatic brain injuries who were functioning at very low levels characteristic of near-vegetative and vegetative states. In 20 patients followed for 16 weeks the scale identified 25% who ultimately showed modest improvement. Interrater reliability was high (r = .95); validity was supported by significant correlations between CNC- and brain-multimodality evoked potential abnormality scores as well as between scores on the CNC and the Disability Rating Scale. The CNC scale was easily learned and it could be completed quickly and cost effectively. Staff found it useful in recognizing among relatively homogeneous low-level patients those most likely to respond to further rehabilitation care. The CNC appears to be useful for justifying ongoing intensive rehabilitation and for preventing premature transfer to lower levels of care.