Encephalopathies

In this lesson we're going to talk about encephalopathy. Remember that pathy means disease or disorder, and encephalo refers to the brain.

So in general encephalopathy is any disorder or disease of the brain. It typically covers chronic or degenerative conditions. But generally it is considered a syndrome of brain dysfunction. Encephalopathy can be caused by dozens of conditions. Anything that causes damage to the brain tissue can cause encephalopathy. These are just a few examples of some common ones you might see. Chronic traumatic encephalopathy is a relatively new term that refers to the Damage Done to brain tissue by repeated blows to the Head. This has come into the light more with all of the studies regarding repeated concussions in professional athletes. You can see in this image that a brain with Advanced chronic traumatic encephalopathy has significant atrophy and wasting away of this brain tissue. Over time these patients struggle more and more with memory loss and personality changes. Unfortunately, there’s no effective treatment at this time. A few other examples that we will talk about are hepatic encephalopathy and Wernicke's encephalopathy. There are also things like metabolic Encephalopathy, hypoxic ischemic encephalopathy, infectious encephalopathy, etc. For your NCLEX you will not need to know the specific details of all of the possible encephalopathies. The most important thing is that you understand that it indicates brain dysfunction. We are going to talk about the two most common encephalopathies that you might see in nursing school as well as on your NCLEX, which are hepatic encephalopathy and Wernicke's encephalopathy, then we’ll look at what they all have in common.

Just like the name suggests hepatic encephalopathy is caused by problems with the liver, specifically liver failure. You'll learn more about this in the liver module in the GI course, but when the liver fails to filter out toxins, they build up in the bloodstream. One of the most common toxins that builds up in the bloodstream is ammonia. That excess ammonia has the ability to cross the blood-brain barrier and cause significant swelling within the brain cells. This is what causes the neurological changes in these patients. You'll see everything from confusion, to restlessness and agitation, to seizures, lethargy, and even coma and death. The diagnosis is made by knowing that the patient has liver failure, and monitoring ammonia levels. To treat this we give a medication called lactulose, which binds to ammonia in the gut and forces it out by way of it's laxative effects. Patients will receive lactulose multiple times a day and therefore will need to use the bathroom multiple times a day. If the patient cannot take the lactulose orally, then we need to use an enema. Many liver failure patients have compliance issues because they don’t like having diarrhea all the time. Because Ammonia is a byproduct of protein breakdown, these patients will need to be on a low protein diet. Because of their altered mental status we also need to make sure that we protect their Airway and provide for safety so that they don't harm themselves or others in their confusion.

Wernicke's encephalopathy is caused by a deficiency in vitamin B1 or thiamine. This is common in anyone with malnutrition, as well as alcoholics. Alcoholics tend to drink instead of eat, and not only does it affect their liver, but the alcohol prevents appropriate absorption of any thiamine they do ingest. Any scans you can see these lighter areas around the midbrain that are showing damage due to thiamine deficiency. The most common symptoms of Wernicke's encephalopathy are Ataxia or uncoordination, confusion and altered mental status, and abnormal eye movements like nystagmus. Treating Wernicke's encephalopathy is simple. We give them more thiamine. Because of their altered mental status, as with all encephalopathies, we need to support their airway and provide for safety until we can reverse the condition.

So all encephalopathies have some symptoms in common. The number one symptom being altered loc or altered mental status. This ranges anywhere from slight confusion and forgetfulness to delirium, lethargy, and coma. Detailed neuro assessments are incredibly important in these patients. We also might see mood or memory changes, seizures, and issues with speech and swallowing due to muscle weakness. To diagnose an Encephalopathy, we will essentially work to identify the cause. We could do blood work to check levels of things like ammonia or thiamine or to look for infection. We will do a CT scan or MRI to look specifically at the brain tissue. And then we could also do a lumbar puncture to look for signs of infection. Ultimately, the goal is just to get a big picture of what's going on with the patient and what the source of the problem is so that we can treat it. As you saw with Wernicke's and hepatic encephalopathy, many of these conditions can be treated by reversing the cause. There are some, like chronic traumatic encephalopathy where the only thing we can do is prevent any further damage.

So again, encephalopathy is a syndrome of brain dysfunction that can be caused by multiple conditions which cause damage to the brain cells. The most common symptom is altered level of consciousness, which could be subtle so detailed assessments are important. We manage encephalopathies by treating the cause whenever possible, because many are preventable or reversible. And again our number one priority in addition to neuro assessments is going to be airway protection and safety.

So those are the basics of encephalopathies. Let us know if you have any questions. Now, go out and be your best self today. And, as always, happy nursing!