Emergency Medicine

ALTERED CONSCIOUS LEVEL

General Medical Emergencies 85

Alcohol-related medical problems

Acute alcohol intoxication is causally related to all types of trauma, including
motor vehicle crashes, incidents in the home, deliberate self-harm, assaults,
drownings, child abuse and falls in the elderly. Chronic use also predisposes to a
variety of medical conditions, and sudden reduction in intake causes withdrawal
problems.

MEASUREMENT OF ALCOHOL LEVEL

● Various methods are available, including a breath test, a urine test, and a
blood level test. None is admissible in a court of law, unless special forensic
kits are used under police direction (see p. 453).
● The Australian legal limit to drive is 0.05 g/100 mL in every state or territory.
● The British legal limit for driving is a blood alcohol level below 80 mg%
(0.08 g/100mL). Intoxication is marked above a level of 150 mg%
(0.15 g/100mL), and coma usually occurs above a level of 300 mg%
(0.30 g/100mL).

Patient with an altered conscious level and smelling of alcohol

DIAGNOSIS AND MANAGEMENT

Never assume that a confused, obtunded or unconscious patient smelling of
alcohol is simply ‘drunk’ until you have considered and excluded all of the
following:

1 Hypoglycaemia
(i) Check a blood sugar, and give 50% dextrose 50 mL i.v. if it is low.
(ii) This may precipitate worsening of the confusion due to a
Wernicke’s encephalopathy.
(iii) Wernicke’s is associated with alcohol abuse and malnutrition,
and causes confusion, ataxia, nystagmus, and bilateral lateral
rectus palsy
(a) give thiamine 100 mg i.v. immediately
(b) this should be routine in suspected alcoholism and in the
malnourished patient receiving dextrose.

2 Head injury
(i) Always remember the possibility of an extradural or subdural
haematoma from a head injury.
(ii) Commence neurological observations and perform a CT head
scan if confusion persists or there is a deteriorating conscious
level (see p. 31).
(a) a skull X-ray is reasonable only in the absence of a CT scan
and may show a fracture, but if normal it does not exclude
intracranial injury.