RAMB - Julho 2016

urrent

clinical

approach

patients

with

disorders

consciousness

ssoc

ras

2016; 62(4):377-384

379

istory

and

clinical

examination

The identification of the cause of the coma must be ini-

tiated by gathering information from family members

and people who may have witnessed the clinical progres-

sion of the patient. It is very important to obtain infor-

mation with respect to the start and progression of symp-

toms (sudden or gradual), life habits (possible use of drugs

or toxic substances), presence of fever, history of trauma,

previous symptoms or diseases, personal and psychiatric

history and medication in use.

The general clinical examination should seek evidence

of systemic conditions that could lead to changes in the

level of consciousness. Vital signs and the examination

of the cardiovascular, pulmonary and gastrointestinal

systems, skin and other systems may provide important

data regarding the etiology of the coma.

The approach should be carried out in a systematic

manner in order for it to be concise and efficient: check-

ing if the airways are patent; checking if breathing is pro-

viding adequate oxygenation (observing the respiratory

pattern, oxygen saturation). Oxygen should be provided

in cases of hypoxemia or establishing airway and ventila-

tory assistance if the GCS score is lower than nine points.

Blood pressure should be measured, verifying the heart

rate and obtaining intravenous access, as well as checking

blood glucose to exclude the suspicion of hypoglycemia.

Signs of trauma, evidence of recent epilepsy crises (tongue

lesions, sphincter release) should be sought, evaluating the

skin, ophthalmoscopy, evidence of exogenous poisoning

(needle marks suggesting drug use), evaluation of the breath,

presence of neck stiffness, and temperature assessment.

Fever is most common in systemic infections such as

pneumonia, bacterial meningitis or viral encephalitis. An

excessively high temperature is related to burns and poi-

sonings by drugs with anticholinergic effects. Hypother-

mia can occur in intoxicated patients, those in shock, in

barbiturate poisoning and myxedema.

An abnormally low pulse suggests a heart block by

medications such as tricyclic antidepressants or anticon-

vulsants. Severe hypertension is observed in intracranial

hemorrhage and hypertensive encephalopathy.

Cherry-red skin coloration is typical of carbon mon-

oxide poisoning. Abrasions, epistaxis and otorrhagia, and

hematoma in the cephalic region suggest a traumatic

cause of coma. Hyperemia of the face and conjunctiva is

a common finding in alcoholics. Maculopapular rash sug-

gests meningococcemia, staphylococcal endocarditis and

typhoid fever. Excessive sweating is found in hypoglyce-

mic patients or those in shock. Excessively dry skin is

found in diabetic ketoacidosis and uremia.

The simple assessment of breath odor can provide

the diagnosis of the cause of the coma. The odor of alco-

hol is easily recognized and in patients with symptoms

such as uremia, hepatic coma, diabetic ketoacidosis and

cyanide poisoning, typical odors can be distinguished by

an acute sense of smell.

eurological

examination

The most important data from the neurological exami-

nation for the location and prognosis include: level of

consciousness, size and pupillary response to light, spon-

taneous or reflex ocular motility, skeletal motor response

and breathing pattern.

Level of consciousness

The assessment of the level of consciousness should in-

clude a description of the patient’s alertness, and response

to verbal and painful stimuli. The goal is to determine

the degree of alteration to the level of consciousness and

have a clinical parameter for evolution and prognosis. It

should be carried out serially and following similar crite-

ria and standards among the examiners for comparative

purposes. It should begin with verbal stimulus and in the

absence of a response, followed by painful stimulus. The

painful stimulus can be applied to the supraorbital re-

gion, nail bed or sternum. Asymmetric motor responses

are suggestive of focal hemispheric damage.

The GCS is a standardized scale used to assess the

level of consciousness originally designed for patients

suffering traumatic injury, which, however, can also be

used to assess any disturbance of consciousness in the

acute phase.

Pupil size and reactivity to light

Pupil reactions have fundamental importance in the ex-

amination as well as the shape, size and symmetry pre-

sented by the pupils. A unilateral pupillary increase (>5.5

mm) is an early indicator of compression or stretching of

the oculomotor nerve (cranial nerve III) as a side effect of

an expansive unilateral process. Initially, there is a de-

crease in reaction to unilateral light.

Pupil size and reactivity are dependent on the action

of the sympathetic and parasympathetic neurons that in-

nervate the pupil dilation and constriction muscles. The

sympathetic system stimulates the contraction of the pu-

pil dilation muscles, causing mydriasis, while the para-

sympathetic system stimulates pupil contraction mus-

cles, leading to miosis. At rest, there is a continuous

tonic action of both the sympathetic and parasympathet-

ic systems. If there is impairment of the sympathetic or