FOUR Score in Children With Non-traumatic Impairment of Consciousness
Condition: Impaired Consciousness
Study type: Observational

Summary: 
      Hypothesis: FOUR score is a better predictor of outcome (in hospital mortality and functional
      outcome at discharge) than GCS in children 5- 18 years age admitted in pediatric ward/ ICU
      with non-traumatic impaired consciousness.

      The assessment of comatose patients is an important part of critical care. The assessment of
      the level of coma relies on clinical scores. The Glasgow Coma Scale (GCS),remains the most
      commonly used scoring system for altered state of consciousness. Despite its widespread use,
      a number of limitations have been identified with GCS like inability to assess verbal score
      in intubated patients and non-inclusion of vital brainstem functions. The FOUR (Full Outline
      of UnResponsiveness) score, a coma scale consisting of four components (eye response, motor
      response, brainstem reflexes, and respiration pattern) was recently proposed by investigators
      from the Mayo Clinic.keeping in view the limitations of GCS, this study was planned to
      compare the new FOUR score with GCS as a predictor of mortality and poor functional outcome
      at hospital discharge.
    

Detailed description: 
      This prospective observational study was carried out from May 2009 to June 2010 in the
      Department of Pediatrics, All India Institute of Medical Sciences, New Delhi. This study was
      approved by institutional ethics committee.

      Participants We enrolled children aged 5-18 years who presented with impaired consciousness
      of less than 7 days duration and were admitted in the pediatric ward or pediatric ICU.
      Children with traumatic brain injury, known vision/hearing impairment, cerebral palsy, mental
      retardation, degenerative brain disease; those already on sedatives or neuromuscular blockade
      and with ongoing seizure or seizure within last 1 hour were excluded from the study.

      Sample Size From the previous studies, it is known that ROC of GCS in children for prediction
      of mortality is 0.7.15 Assuming FOUR score to be better predictor of outcome (area under
      curve for FOUR score assumed to be 0.8), the sample size calculation was done using MedcalcR
      version 9.2.0.1. The correlation between both the scores and outcome was assumed to be 0.7.
      Keeping α-level as 0.05 and β-level as 0.20, the sample size was calculated to be 70.

      Assessment Procedure The investigator (GK) was trained with the standardized video examples
      included in a DVD prepared by the developers of the FOUR score (Wijdicks et al10). After
      training, the investigator demonstrated the score on 2 patients while being supervised by
      Pediatric Neurologist. There was periodic training of the investigator every month by
      reviewing the case examples in DVD and rechecking the score periodically.

      Written informed consent was obtained from the parents/ guardians for all patients. All the
      observations (required for the FOUR score and GCS) and investigations (required for PIM2) are
      done routinely in the children admitted in Pediatric ward/PICU. No additional investigations
      or interventions were done primarily for the study. Standardized care based on current
      guidelines was provided to all the patients.

      Rater (GK) was given one page hand-out with written instructions describing both the FOUR
      score and the GCS. The GCS and the FOUR score applied by the rater within two hours of
      admission and before starting sedatives or neuromuscular blockade. The rater was primary
      investigator in all the patients. The sequence of application of the scores was randomized
      using block randomization with block size of 10 patients.

      Severity of illness was assessed by PIM2 score16. For PIM2, the values of various variables
      at time of admission to Pediatric ward/PICU were recorded. PIM 2-based mortality index was
      evaluated based on the regression equation as published in the literature.The children with
      impaired consciousness and reduced mental state were classified as obtunded, stuporous or
      comatose based on classification given by Taylor et al.17 The etiology was determined based
      on review of the clinical, laboratory and imaging data by the Pediatric Neurologist.

      The patient was followed till discharge/ in-hospital mortality. The functional outcome of the
      patients was assessed by the Pediatric Overall Performance Category (POPC)18 at the time of
      PICU discharge or 1 month following admission whichever was earlier. This scale ranges in
      value from 1 to 6 with a value of 1 indicating normal functioning and a value of 6 indicating
      brain death. Children were considered to have poor outcomes if they scored 3-6 on the POPC
      scale, consistent with moderate to severe disability to vegetative state, coma or brain
      death. The POPC score was obtained through direct questions about the child's ability to
      perform age-appropriate activities, use of rehabilitative services, and physical
      disabilities.
    

Observational model: Case-Only
Time perspective: Prospective
Sampling method: Probability Sample
Study population: 
        Children aged 5-18 years, admitted in PICU or pediatric ward with impaired consciousness of
        less than 7 days duration