0071643192.pdf

PSYCHOBEHAVIORAL DISORDERS

The blood alcohol concentration (BAC)

After the consumption of a standard drink (12 oz of beer, 5 oz of wine or 1.25 oz
of 80 proof liquor), the BAC will peak within 30 minutes. The resulting BAC
is determined by gender and weight. Two standard drinks will typically raise
the BAC to 0.05% in a 70-kg male (higher in females). In most states, 0.08%
is considered legally intoxicated.

A nontolerant patient’s BAC typically correlates with a particular presentation
(see Table 16.1). However, an alcohol-dependent person will exhibit toler-
ance to increased levels of blood alcohol.

Alcohol is metabolized at a constant rate, ie, zero order kinetics. A typical rate
of metabolism is 0.01–0.02% per hour. However, there is great variability in an
individual’s ability to metabolize alcohol. Experienced drinkers may metabolize
alcohol as fast as 0.04% per hour, but patients with advanced liver disease will
metabolize slower.

ALCOHOLINTOXICATION

SYMPTOMS/EXAM/DIAGNOSIS

■ Recent ingestion of alcohol
■ Maladaptive behavior such as sexual or aggressive behavior, impaired
judgment, labile mood, impaired social/occupational functioning
■ Physical signs such as slow or slurred speech, incoordination, unsteady
gait, nystagmus, impairment of attention or memory, stupor or coma
■ Rule out other medical conditions.

DIFFERENTIAL

Opioid intoxication, sedative/hypnotic use, toxic overdose (clonidine, organo-
phosphates, phenothiazines), carbon monoxide poisoning, hypoglycemia, hypoxia,
CNS infections, postictal states, pontine hemorrhage

TREATMENT

■ ABCs (intubate if airway not protected)
■ Supportive care: IV fluids or banana bag (magnesium, thiamine, folate,
multivitamin), dextrose, and electrolyte repletion if indicated
■ Imaging if trauma is suspected
■ Antipsychotic agent for behavioral control if indicated

TABLE 16.1. BAC Correlated With Typical Presentation in Nontolerant

Alcohol-Intoxicated Patient

BAC (mg/dL) CLINICALPRESENTATION

30 Attention difficulties, mild euphoria

50 Coordination problems

100 Typical drunk-driving parameter, ataxia

200 Confusion, decreased consciousness

>400 Seizure, coma, could result in death

(Reproduced, with permission, from Hillard R, et al. Emergency Psychiatry.

New York: McGraw-Hill, 2004:140.)