Why is the pupillary reflex performed frequently in a comatose patient?
Pupillary light reflex (PLR) is simply the change in pupil size that occurs after a light stimulus. It provides information on the brainstem integrity in the comatose patients (15).
How do you assess a patient in a coma?
The key components of the neurological examination of the comatose patient are:
- level of consciousness (Glasgow Coma Score — list the components; e.g. E4V5M6 = GCS 15)
- the pattern of breathing.
- size and reactivity of the pupils.
- eye movements and oculovestibular responses.
- motor responses (tone, reflexes and posturing)
What does no pupil response mean?
Abnormalities such as an irregular pupil size or shape, or a delayed or nonreactive pupil can be indicative of significant head trauma. A score of 2 means both pupils are non-reactive to light; a score of 1 means one pupil is non-reactive; and a score of 0 means neither pupil is non-reactive. Improving GCS Score.
Do eyes respond to light in a coma?
How the eyes react to light will help the doctor determine the extent of brain damage. If the pupil does not constrict but remains dilated, there may be a large mass causing the brain damage. If the pupil reacts to light even though a person is in a deep coma, then a mass is not likely.
What part of the brain controls pupillary reflex?
The pupillary light reflex pathway lies at the level of the midbrain-diencephalic junction and involves the pretectal olivary nucleus of the pretectal area, which lies anterolateral to the superior pole of the superior colliculus; the posterior commissure, which forms the roof of the cerebral aqueduct (of Sylvius); the …
What is a key finding in the assessment of a patient in a coma?
The patient exhibits little or no spontaneous activity, and shows little motor or verbal activity once aroused. Coma indicates a state in which the patient is not arousable at all to verbal or physical stimuli, and no attempt is made to avoid painful or noxious stimuli.
Does dilated pupils mean brain dead?
Fully dilated pupils are evidence of preserved sympathetic outflow and are incompatible with the diagnosis of brain death as it is commonly understood (2). The pupils of the brain-dead patient are midposition (4 to 6 mm in diameter) and fixed to light (3).
Can a brain dead person blink their eyes?
Some of the signs of brain death include: The pupils don’t respond to light. The person shows no reaction to pain. The eyes don’t blink when the eye surface is touched (corneal reflex).
How is the neurological examination used in coma?
Introduction: The neurological examination is a resource used in evaluating patients who are in coma. Anaesthesia can be a factor that exerts an influence on the findings. We evaluated the examination of the comatose patient in the case of patients anaesthetised with propofol in order to define its clinical value.
What are the objectives of pupillary evaluation in coma?
Objectives: To determine the usefulness of bedside evaluation of pupils in determining the aetiology of coma by adopting a probabilistic approach.
What causes small reactive pupils in a coma?
Pupils (Fig. 1. 35): Metabolic causes of coma usually cause small reactive pupils. Many toxins and drugs administered may also have effects on the size of the pupils, and pharmacologic mydriasis can inadvertently occur in patients treated with aerosols after extubation.
How many patients have coma of unknown aetiology?
Overall, 60% of the patients had coma of a metabolic origin and 40% a structural origin. Two patients had coma of unknown aetiology; it was classified as of metabolic origin based on the final decision of the primary physician and the investigators.