Go Back

Altered mental status

24 Jul 2016

By: Karen Gray, RN, CCDS for IMCU

View as a webpage  

Encephalopathy is defined as an acute or sub-acute generalized alteration in brain function due to a systemic underlying cause. It is reversible and resolves when the underlying condition is corrected. There are several types of encephalopathy and with ICD 10 it is important to document the specific type. Here are a few:

  • Metabolic encephalopathy is usually due to things like fever, dehydration, electrolyte imbalances, acidosis, hypoxia, infection and organ failure.
  • Toxic/metabolic encephalopathy suggests a combination of toxic and metabolic factors.
  • Septic encephalopathy is a clinical term that represents a manifestation of severe sepsis.
  • Hepatic encephalopathy describes a spectrum of impairments in patients with severe liver disease. This can range from confusion to combativeness and may affect level of consciousness. An elevated ammonia level confirms this diagnosis, because ammonia is a neurotoxin.
  • Hypertensive encephalopathy is associated with hypertensive crisis.
  • Hypoxic or anoxic encephalopathy is usually permanent, chronic brain damage due to sustained hypoxia.

Delirium in ICD 10 is classified as a mental disorder or a symptom. It is defined as “A disturbance in attention and awareness that develops over a short time.” It is classified by the underlying cause (for example, delirium due to drug or chemical intoxication or withdrawal). It can be due to a physiological consequence of another medical condition (for example, acute delirium due to metabolic encephalopathy).

Dementia vs. encephalopathy
It is sometimes hard to validate the diagnosis of encephalopathy in a patient with known dementia. Just remember a dementia patient has encephalopathy when there is an acute or sub-acute mental status change that improves back to baseline once the underlying condition is treated. If the patient’s mental status does not improve it is not likely to be encephalopathy.

What does this mean for you?

Encephalopathy is a highly scrutinized diagnosis right now.

You are likely to be queried:

  1. If you document AMS (altered mental status) for a more specific diagnosis.
  2. If you document encephalopathy you will likely be queried about the type of encephalopathy.
  3. If you document delirium you will likely be queried for acuity and underlying cause.
  4. If the patient has sepsis and encephalopathy you will likely be queried to see if the encephalopathy is due to the sepsis or another condition.
  5. If you document hepatic encephalopathy it must state if it is with or without coma or you will likely be queried.

If you have any questions please feel free to discuss this with any clinical documentation specialist.