FOUR Score Coma Scale

Full Outline of Unresponsiveness

Geschiedenis

1974 Teasdale and Jenett

Attempt to bring uniformity to the clinical examination and clinical communication about the level of consciousness

GCS

Not designed to capture distinct details of the neurologic examination

FOUR

FOUR

FOUR

FOUR

Voordelen

Measurement of brainstemreflexes

Determination of eye opening, blinking and tracking

A broad spectrum of motor responses

Presence of abnormal breath rhythms and a respiratory drive

NO assessment of verbal responses (intubation)

Eye response

Differentiation betweenVegetative state

(eyes open but do not track)

Locked in syndrome(eyes open, blink and track vertically on command)

Motor assessment

Combination:Withdrawal reflex

Decorticate rigidity

Complex command (alert)

Severe cerebral dysfunction

(Myoclonic status epilepticus)

Brainstem components

Pons

Mesencephalon

Medulla oblongata

Various combinations

Breathing components

Cheyne-Stokes respiration

Irregular breathing

Bihemispheric or lower brainstem

dysfunction

Intubation: presence or absence of a

respiratory drive

Studie

Different types of examinersWatched a 20min instruction on the FOUR

score (videos with patient examples)

Exclusie sedation/neuromuscular function blockers

Studie

4 categories:Alert

Drowsy

Stuporous

Comatose

Each patient was rated on both scales by

two different raters (1 hours)

Outcome assessment

A robust predictor of: In-hospital mortality (withdrawal of life support)

Functional outcome at hospital discharge

Clinical diagnosis of brain death

Morbidity at 3 months

Modified Rankin Scale

Rankin score

0 : No symptoms

1 : No evident disability despite symptoms

2 : Slight disability, with an inability to carry

out all previous activities

3 : Moderate disability, with the need for

some help but the ability to walk without

assistance

Rankin score

4 : Moderately severe disability, with the

inability to walk without assistance or to

attend to bodily needs without assistance

5 : Severe disability, with the patient being

bedridden and incontinent and requiring

constant nursing care

6 : Death

Ideal coma scale

Reliable (measures what it is supposed to measure)

Valid (yields the same results with repeated testing)

Linear (gives all component equal weight)

Easy to use (provides simple instructions without the need for tools or cards)

Shortcomings GCS

Verbal componentOrientationQuickly abnormal (agitation/confusion)

Conversely no respose alert

Intubation

Poorly assessing patients with less severe degrees of coma

Shortcomings GCS

No assessment of brainstem reflexes(eye movements, complex motor responses)

Reliability

Numerically toward motor responses

Linearity

May not detect subtle changes

Attempts to improve GCS (lengthy)

FOUR: Voordelen

High degree of: Internal consistency

Interrater reliability (interobserver agreement)*

Intubated patients

Brainstem reflexes

Respiratory patterns

Further characterizes the severity of the comatose state in patients with lowest GCS (Mortality)

* High proportion alert patient (ER)

FOUR: Voordelen

Detects early changes in consciousness

(Acute metabolic derangements, sepsis, shock, other nonstructural brain injuries)

Frequent use of mild sedation affects: Eye opening

Motor response

NOT:Brainstem reflexes

Respiration.

Limitations

4 maal: familiarity

Number of patients

Nurse/nurse

Target enrollment cohort

Alert patients

Single center study

Conclusion

Easily taught, simple to administer and provides essentiel neurologic information

limited experience neuroscience

Accurately predicts pour outcome

Interobserver agreement (GCS)

Detect occurence of brain death

Diagnose a locked-in syndrome

Referenties

Vivek et all. Validity of the FOUR score coma scale in the medical intensive care unit. Mayo Clinic Proc. 2009;84(8):694-701

Latha et all. Validation of a new coma scale, the FOUR score, in the emergency department. Neurocrit Care. 2009; 10:50-54

Chris et all. Further validation of the FOUR score coma scale by intensive care nurses. Mayo Clin Proc. 2007; 82(4):435-438

Eelco et all. Validation of a new coma scale: the FOUR score. Ann Neurol. 2005;58:585-593