Alcohol Withdrawal In ICU
In this article we are going to be discussing alcohol withdrawal in the ICU setting. All family physicians practicing hospital medicine will have to manage alcohol withdrawal. Our goal today is to discuss those cases that are more severe and require ICU level care.
Alcohol abuse and dependence is extraordinarily common in our society. It is estimated that there are roughly 8 million people who are dependent on alcohol in the United States. About 12% of American adults will have a problem with alcohol dependence at some point in their lifetime.
The healthcare implications of these numbers are tremendous. Every year about a half a million people are hospitalized for alcohol withdrawal. It certainly behoves providers to be comfortable with the management of this common condition.
Pathophysiology Of Alcohol Withdrawal
You may recall from medical school that ethanol stimulates GABA receptor complexes in the brain. GABA is the primary inhibitory neurotransmitter in the brain. By stimulating this complex ethanol causes central nervous system depression. Over prolonged periods of exposure, the theory is that the body down regulates GABA activity to balance this constant stimulation by ethanol
Additionally, ethanol also inhibits glutamate, which is one of the major excitatory neurotransmitters in the brain. With chronic alcohol exposure the body adapts by increasing sensitivity to glutamate to maintain CNS arousal.
When an alcohol dependent patient stops consuming, their nervous system still has down regulated GABA activity and up regulated glutamate activity. |This results in a state of over activity and hyper stimulation of the nervous system.
This hyperexcitability is what causes the symptoms of alcohol withdrawal. Symptoms may include mild excitatory effects such as tremor, insomnia, anxiety, nausea, diarrhea and diaphoresis. More severe symptoms include confusion, hallucinations, extreme agitation, combativeness psychosis seizures and death.
Symptoms of withdrawal can start in as little as six hours after cessation of drinking, but may sometimes be delayed up to 48 to 96 hours after the last drink.
Delirium tremens is a clinical state of delirium hallucinations, agitation, tachycardia, hypertension and fever. It typically begins 48 to 96 hours following cessation of drinking and may last up to seven days. Delirium tremens has a 5% mortality rate.
Clearly, alcohol withdrawal is a dangerous problem. What is our approach to treatment?
The first step is recognizing the condition, which isn't always easy. Some patients will present to the ER complaining that they are going through withdrawal requesting to be admitted for symptom management.
However, often patients may simply present with confusion and be unable to give a history. The symptoms of withdrawal can be nonspecific. If a patient can't give a history it's important to rule out other organic diseases.
Also, very often patients will present with complications of their withdrawal such as aspiration and pneumonia. It's up to the clinician to obtain a good substance use history.
The other situation in, which we frequently run into alcohol withdrawal particularly in the ICU, is when we don't realize that a patient was dependent on alcohol prior to admission. They may be admitted to the ICU intubated for a COPD exacerbation and suddenly 48 hours later become tachycardic tremulous confused and febrile.
This can become confusing because other conditions, such as infection or ICU delirium, can cause similar symptoms.
Clinicians must always think of alcohol withdrawal when a patient has an acute mental status change a couple days into their hospitalization.
When assessing pain with alcohol withdrawal, it's important to keep in mind that due to the high morbidity of the condition. Many patients will need to be monitored in the intensive care unit.
In general, patients going through alcohol withdrawal who also have significant comorbid medical conditions should be monitored in the ICU. This includes patients with significant cardiac disease, severe electrolyte disturbances, respiratory distress or GI bleeding.
You may also consider ICU admission if the patient has a history of significant withdrawal complications such as DTS or withdrawal seizures. Many patients wind up being transferred to the ICU because they require a continuous infusion of benzodiazepines to control their symptoms.
Finally, some patients also require ICU level care because they become so agitated and combative that they need to be chemically sedated and restrained to prevent them from injuring themselves.
Treatment Of Withdrawal
When it comes to treating withdrawal, our goals are to attenuate the CNS excitation, thereby making the patient more comfortable and also try to prevent seizures, metabolic derangements, and other more severe complications.
Patients should be supported with IV fluids and nutritional supplementation. Thiamine followed by glucose should be given to correct efficiency and prevent encephalopathy.
A multivitamin containing folate in either oral or IV form should also be administered.
Alcoholic patients also frequently have low potassium, magnesium and phosphate levels. Those should be measured and corrected as needed. Generally, we make patients and NPO because they are at risk of seizure and aspiration.
The pharmacologic mainstay to therapy for alcohol withdrawal is treatment with benzodiazepines. These medications work by enhancing inhibitory GABA effects, thereby lessening the CNS excitation that occurs in withdrawal.
Benzodiazepines help reduce the uncomfortable symptoms of withdrawal such as tremor and agitation. They can also help prevent the development of withdrawal seizures.
Diazepam and Lorazepam are frequently used. In significant withdrawal they are used in IV form but NPO may be used in more mile cases.
Benzodiazepine dosing is often determined using a standardized symptom scale called the CIWA scale. The CIWA scale is used to try to quantify the extent of a patient's symptoms.
The patient's nurse assesses these variables and then grades each of these symptoms on a numerical scale. Standard orders are usually written to administer a certain dose of benzodiazepine based on the patient's score. A nurse may do this assessment every 15 to 30 minutes initially then slowly reduce the frequency of checks based on the patient's clinical picture.
In ICU level patients that are at high risk of significant withdrawal, we often administer scheduled benzodiazepines in addition to this symptom driven protocol to ensure the patient is being adequately treated. We often find that patients with severe withdrawal are requiring large amounts of IV benzodiazepines very frequently.
When this occurs is most practical to switch the patient to a continuous IV infusion. This requires ICU monitoring at most institutions due to the frequent dose reassessment required as well as the risk of sedation.
Some patients continue to have significant symptoms despite treatment with high doses of benzodiazepines. For refractory agitation phenobarbital or propofol can be administered. These agents will cause significant sedation.
An intubation and mechanical ventilation is usually indicated when starting these medications.
For withdrawal seizures patients may receive additional doses of benzodiazepines or phenobarbital. For treatment of delirium and hallucinations, that often accompany alcohol withdrawal, antipsychotics can be quite affected adjuncts.
Haloperidol is frequently used. It is available in IV and IM forms. Haloperidol can lengthen the QT interval. Baseline EKG with periodic reassessment is recommended if this medication is going to be used repeatedly.
Keep in mind that none of these agents should be used as mono therapy for withdrawal. They are all adjunctive treatments. The safest and best study drugs to use alone are the benzodiazepines.
Resolution Of Withdrawal
Alcohol withdrawal usually resolves over several days. In some cases, particularly with delirium tremors, patients may have refractory symptoms for a week or more. As patients become gradually less symptomatic, the doses of benzodiazepines are slowly decreased until there is no further need.
All patients who have undergone alcohol withdrawal in the hospital should be offered AODA counseling and outpatient follow-up.
In summary, today we've discussed the pathophysiology and symptoms of alcohol withdrawal and how they are related to CNS excitation. We have discussed the indications for ICU monitoring and alcohol withdrawal.
Finally, the primary therapies for alcohol withdrawal are benzodiazepines for symptom control and prevention of seizures and nutritional and fluids support.