Alcohol Intoxication
Alcohol intoxication is one of the most common emergency presentations. Management involves ABCDE assessment, excluding co-existing pathology, treating complications, and addressing alcohol use disorder on discharge.
Key Facts
- Alcohol-related ED attendances account for approximately 12-15% of all presentations to UK emergency departments
- Blood alcohol level >400mg/dL (87 mmol/L) can be fatal; however, chronic drinkers may tolerate very high levels
- Key differential diagnoses to exclude: Head injury (intoxicated patients fall), hypoglycaemia, hepatic encephalopathy, Wernicke's encephalopathy, sepsis, overdose
- Wernicke's encephalopathy triad: Confusion, ataxia, ophthalmoplegia - treat with IV Pabrinex (thiamine) BEFORE glucose
- Pabrinex prophylaxis: IV pairs 1+2 TDS for 3-5 days if malnourished, chronic alcohol, suspected deficiency
- Alcohol withdrawal can be life-threatening - onset 6-24h; peak 24-72h; delirium tremens at 48-72h (mortality ~5%)
- CIWA-Ar score guides chlordiazepoxide dosing for alcohol withdrawal
- Always check blood glucose, consider head injury, and assess for concurrent drug ingestion in intoxicated patients
Overview
Key Facts
Alcohol intoxication and its complications represent a major burden on UK emergency services. The key challenge is not managing intoxication itself but identifying and treating co-existing or mimicking conditions that may be masked by alcohol.
Epidemiology
Alcohol-related hospital admissions in England exceed 1 million per year. ED attendances related to alcohol account for approximately 12-15% of all presentations (higher at weekends and overnight). Alcohol-related deaths in the UK: approximately 10,000 per year. Alcohol misuse costs the NHS approximately £3.5 billion annually.
Aetiology
- Acute intoxication: Binge drinking, chronic heavy drinking
- Alcohol use disorder: Affects approximately 6% of adults in England
- High-risk groups: Young adults (binge drinking), homeless populations, those with mental health comorbidity
Pathophysiology
Ethanol is a CNS depressant acting primarily via GABA-A receptor potentiation and NMDA receptor inhibition. It causes dose-dependent sedation, impaired coordination, slurred speech, and at high doses, respiratory depression and coma. Chronic use leads to neuroadaptation (GABA downregulation, NMDA upregulation), explaining tolerance and the potentially life-threatening withdrawal syndrome when alcohol is ceased.
Clinical Presentation
Stages of Intoxication
- Mild (50-150mg/dL): Disinhibition, impaired judgement, slurred speech
- Moderate (150-250mg/dL): Ataxia, dysarthria, emotional lability, nausea/vomiting
- Severe (250-400mg/dL): Stupor, marked ataxia, hypothermia, risk of aspiration
- Potentially fatal (>400mg/dL): Coma, respiratory depression, cardiovascular collapse
Red Flags
- Reduced GCS not proportionate to estimated alcohol intake - consider head injury, co-ingestion, metabolic cause
- Focal neurological signs - CT head to exclude intracranial pathology
- Hypoglycaemia - common in chronic drinkers and malnourished patients
- Hypothermia - particularly outdoor exposure while intoxicated
- Persistent vomiting - risk of Mallory-Weiss tear, aspiration, Boerhaave syndrome
- Confusion disproportionate to alcohol level - Wernicke's encephalopathy
Differential Diagnosis
| Diagnosis | Key Features | Investigation |
|---|---|---|
| Alcohol intoxication | History, smell, clinical features | Blood alcohol, clinical |
| Head injury | Fall, external signs, focal neurology | CT head |
| Hypoglycaemia | Sweating, tremor, confusion | Blood glucose |
| Wernicke's encephalopathy | Confusion, ataxia, ophthalmoplegia | Clinical (treat empirically) |
| Hepatic encephalopathy | Chronic liver disease, asterixis | Ammonia, clinical |
| Drug co-ingestion | Variable features | Drug screen, paracetamol level |
| Diabetic ketoacidosis | Kussmaul breathing, ketotic breath | Glucose, ketones, ABG |
| Methanol/ethylene glycol | Visual disturbance, severe acidosis, osmolal gap | ABG, osmolality |
Diagnosis / Investigation
Bedside
- ABCDE assessment: Airway protection is priority
- Blood glucose: Immediately - treat hypoglycaemia
- GCS: Serial monitoring - should improve over time; if not, investigate further
- Temperature: Hypothermia risk
- ECG: Arrhythmias (holiday heart syndrome - AF)
Bloods
- Blood alcohol level: Confirms intoxication; correlate with clinical state
- Blood glucose: Hypoglycaemia (impaired gluconeogenesis)
- U&Es: Electrolyte disturbance (hyponatraemia, hypokalaemia, hypomagnesaemia)
- LFTs: Acute/chronic liver damage
- FBC: Macrocytosis (chronic alcohol use), thrombocytopenia
- Paracetamol level: Always check for co-ingestion
- VBG/ABG: Lactate, pH, ketones
- Amylase/lipase: If abdominal pain (pancreatitis)
Imaging
- CT head: If head injury suspected, focal neurology, GCS not improving, anticoagulated
Special Tests
- AUDIT score: Alcohol Use Disorders Identification Test - screen before discharge
- Serum magnesium: Often low in chronic alcohol use
Management
Non-pharmacological
- Airway protection: Recovery position if unable to maintain airway; intubation if GCS ≤8 with no improvement
- Observation: Safe, monitored environment; serial GCS
- Rehydration: IV fluids (0.9% NaCl or Hartmann's) if dehydrated
- Warming: If hypothermic
- Brief intervention: For hazardous/harmful drinking - evidence-based approach at discharge
Pharmacological
- IV glucose: 100mL 20% glucose if hypoglycaemic - but give IV Pabrinex FIRST if Wernicke's suspected
- IV Pabrinex (high-potency B vitamins including thiamine): Pairs 1+2 TDS for 3-5 days if malnourished, suspected Wernicke's, or chronic alcohol use - BEFORE glucose administration
- Antiemetics: Ondansetron 4mg IV if significant vomiting
- Alcohol withdrawal management (if developing):
- Chlordiazepoxide reducing regimen (e.g., 30mg QDS day 1, reducing over 5-7 days) - guided by CIWA-Ar score
- Symptom-triggered dosing is safer than fixed-dose regimens
- Pabrinex throughout withdrawal period
Surgical/Interventional
- Not usually required; manage complications as they arise
Referral Criteria
- AUDIT score ≥8: Brief intervention; ≥16: Referral to alcohol services
- Dependent drinking: Alcohol liaison nurse, community alcohol team
- Recurrent presentations: Safeguarding, social services, dual diagnosis team if mental health comorbidity
- All deliberate self-harm with alcohol: Psychiatric assessment
Prognosis
- Acute intoxication: Self-limiting if uncomplicated; death from aspiration, respiratory depression, or hypothermia is preventable
- Alcohol-related liver disease: Leading cause of liver disease in the UK; ~6,000 deaths/year
- Alcohol withdrawal: Mortality from delirium tremens ~5% if untreated, <1% with treatment
- Brief interventions: NNT 8 to reduce hazardous drinking by 1 person
- Wernicke's encephalopathy: If untreated → 80% develop Korsakoff's syndrome (irreversible amnesia)
Other Relevant Information
CIWA-Ar Score Components
| Domain | Assessment |
|---|---|
| Nausea/vomiting | Severity 0-7 |
| Tremor | Severity 0-7 |
| Anxiety | Severity 0-7 |
| Agitation | Severity 0-7 |
| Paroxysmal sweats | Severity 0-7 |
| Orientation | Severity 0-4 |
| Tactile disturbances | Severity 0-7 |
| Auditory disturbances | Severity 0-7 |
| Visual disturbances | Severity 0-7 |
| Headache | Severity 0-7 |
Score >8: Treat; >15: Moderate withdrawal; >20: Severe withdrawal.
Alcohol Withdrawal Timeline
| Time After Last Drink | Features |
|---|---|
| 6-12 hours | Tremor, anxiety, sweating, tachycardia |
| 12-24 hours | Alcoholic hallucinosis (visual/auditory) |
| 24-48 hours | Withdrawal seizures (generalised tonic-clonic) |
| 48-72 hours | Delirium tremens (confusion, hallucinations, autonomic instability) |