Alcohol withdrawal
Definition
Condition that occurs in alcohol abusers as a result of decrease or cessation of alcohol drinking
Results in blood alcohol levels below the level to which the drinker has become habituated
Begins about 4 to 12 hours after the last drink and may progress to delirium tremens with seizures, hallucinations, coma, and death
Risk Factors
Abrupt withdrawal of alcohol
The severity of symptoms is proportional to the previous duration and level of alcohol consumed
Differential diagnosis
Sympathomimetic intoxication
Hepatic encephalopathy
Benzodiazepine withdrawal
Opioid withdrawal
Anticholinergic poisoning
Epidemiology
On a worldwide basis, alcohol misuse is responsible for 1.8 million deaths and 58.3 million disability-adjusted life years
In 2003, the prevalence of disorders related to alcohol use was 1.7% in developed countries
In England, 52,270 hospital admissions in 2005/2006 were directly related to alcohol abuse and there were 6,570 alcohol-related deaths
The reporting rate for alcohol-related deaths in the UK is rising, from 6.9 cases per 100,000 in 1991 to 13.4 per 100,000 in 2006
Aetiology
Aetiology is not known
Chronic alcohol use is associated with:
an up-regulation of postsynaptic glutamate receptors
or a down-regulation of postsynaptic gamma-amino butyric acid (GABA) receptors
Alcohol-related seizures are likely the result of a combination of brain pathology, irritability related to alcohol withdrawal, or trauma related to alcoholism
Alcoholic hallucinosis does not have a definitive aetiology; it is known to be related to the severity of dependence and frequency of major withdrawal
Clinical features
Alcohol use
Structured approach to drinking habits includes asking about alcohol use in the past year and using the CAGE questionnaire to assess whether the patient needs a referral
Patients are at risk for major withdrawals if they:
drink more than 2 litres of wine or equivalent quantity of hard liquor
have a history of heavy alcohol use for more than 5 years
usually drink throughout the day
have a prior history of withdrawal
Change in mental status
Patient has severe memory disturbances, remains disoriented to time, place, and person, and has waxing and waning in the level of consciousness
Seizures
Occurs in 1% to 3% of patients with alcohol withdrawal syndrome
Usually happens in the early phase of withdrawal (up to 2 days)
Most patients have one seizure that is usually tonic-clonic in nature
Focal onset and status epilepticus are rare
Hallucinations
Examples of visual hallucinations include insects crawling on self or animals circling the bed
Tactile hallucinations include sensation of pins or electric shocks all over the body and insects crawling on the skin
Associated with delirium tremens (DT), which occurs in 5% of patients hospitalised for alcohol withdrawal
Delusions
Associated with DT
Tremor
Associated with minor withdrawal
Also a feature of delirium tremens
Nausea and vomiting
Associated with minor withdrawal
Hypertension
Associated with minor withdrawal
Tachycardia
Associated with withdrawal of any severity
Fever
Associated with major withdrawal and DT
Pathophysiology
Prolonged exposure causes adaptive changes in the brain receptors and neurotransmitters
Responsible for various effects such as addiction, tolerance, and withdrawal
Frequent withdrawal episodes are associated with irreversible brain damage from cell death
This phenomenon has been demonstrated in animal studies
There are multiple neurotransmitters in the brain that play a role in alcohol withdrawal
Their effects are interactive, and some of the neurotransmitters involved include glutamate, GABA, opioid receptors, dopamine, and serotonin receptors
One of the excitatory neurotransmitters is glutamate, which acts through the fast-channel NMDA (N-methyl D-aspartate)
Alcohol inhibits glutamate, resulting in an increase in the NMDA receptors
When an individual stops drinking alcohol, inhibitory effects of alcohol on glutamate stop, and excitatory effects manifest clinically
One of the inhibitory chemical substances in the brain is GABA, which acts through the GABA-A receptor
It has been shown that increasing the concentration of GABA in the brain produces similar effects to alcohol intoxication
It has also been noted in studies that repeated exposure to alcohol can reduce GABA hyperpolarisation and neuronal inhibition, resulting in development of tolerance
Dopamine release has been noted in the brain when alcohol is ingested, and alcohol withdrawal is associated with inhibition of dopamine
Alcohol use is also associated with an increase in endorphins, and chronic use is associated with lower levels of endorphins
Studies show that an increase in serotonin has been noted with alcohol consumption
Has shown to be responsible for development of tolerance, intoxication, withdrawal, and regulation of alcohol consumption
Increased craving for alcohol after repeated detoxifications is referred to as kindling
This occurs as a result of long-term changes in neurons, and explains the progression of withdrawal
Investigations
Serum urea and creatinine
Elevated, normal, or reduced
Dehydration may occur in a delirious patient and may lead to impaired renal function
Uraemic encephalopathy can mimic alcohol withdrawal delirium because of change in mental status
LFTs
All parameters may be elevated
May suggest additional diagnoses such as alcoholic hepatitis
Toxicology screen
May be positive for other drugs of abuse
May be used to determine other causes for altered mental status or abnormal vital signs
Serum and urine drug testing (both quantitative and qualitative) should be based on clinical suspicion at time of decision making
Electrolyte panel
Metabolic acidosis
Lactic acidosis may be related to alcoholic seizures, ketoacidosis, or ingestion of other alcohols
CT head
To exclude other causes of the clinical presentation if indicated
Management
a) conservative
Supportive care
Vitamin supplementation
Thiamine supplementation is given if Wernicke’s encephalopathy is suspected
Other water-soluble vitamins that may need to be supplemented during hospital or emergency department course include folic acid and magnesium
b) medical
benzodiazepine or clomethiazole
25-100 mg orally/intravenously/intramuscularly every 4-6 hours, reduce dose as symptoms abate, maximum 300 mg/day
5-10 mg orally/intravenously/intramuscularly every 6-8 hours
1-4 mg orally/intravenously/intramuscularly every 6-8 hours
magnesium
Severe hypomagnesaemia (<1 mg/dL) and symptomatic patients in the emergency setting may need up to 2 g of magnesium sulphate given by intravenous infusion
c) surgical
n/a
Prognosis
Patients may complain of persistent insomnia and autonomic symptoms for a few months after acute withdrawal phase
These symptoms usually last about 6 months
About 50% of patients remain abstinent for a year
Relapse prevention can be achieved by counselling strategies, self-help groups (e.g., Alcoholics Anonymous), and pharmacotherapy