02.02 Levels of Consciousness (LOC)

Join NURSING.com to watch the full lesson now.

Included In This Lesson

Study Tools



Neurological changes can occur for various reasons – noticing small changes can mean the patient gets help sooner.

Nursing Points


  1. Priority assessments
    1. Alertness
    2. Orientation
    3. Response to Pain


  1. Normal
    1. Conscious
    2. Awake & Alert
    3. Awakens easily from sleep
    4. Oriented to:
      1. Person
      2. Place
      3. Time
      4. Situation
    5. Follows Commands
  2. Confused
    1. Awake, alert
    2. Unable to answer all orientation questions (i.e. A&O x 1-2)
    3. Difficulty following commands
    4. Slow thought process
    5. Memory loss
    6. Possible causes:
      1. Sleep deprivation
      2. Malnutrition
      3. Infection
      4. Toxemia / Acidosis
      5. Hypoglycemia
  3. Delirious
    1. Confused and disoriented AND:
    2. Restless or Agitated
    3. Possible hallucinations or delusions
    4. Trouble paying attention
    5. Possible causes:
      1. ICU delirium
      2. Sundowner’s
      3. Encephalopathies
  4. Somnolent
    1. Excessive drowsiness
    2. Can’t keep eyes open / stay awake
    3. Responds with mumbles only
    4. Require increasingly painful stimuli to arouse
  5. Obtunded
    1. Might be awake, but not alert
    2. No interest or response to surroundings
    3. Slowed responses
    4. “Looking right through you”
  6. Stuporous
    1. Sleep-like state
    2. Little to no spontaneous activity
    3. Respond only with grimacing
    4. Withdraw to pain
    5. Increase painful stimuli to obtain best response
  7. Comatose
    1. Unable to arouse
    2. NO response to stimuli
    3. Assess for cough/gag reflex
    4. Assess for airway protection

Therapeutic Management

  1. Change in LOC
    1. Check SpO2
    2. Check Blood glucose
    3. Intervene for those if needed
    4. Notify Provider if not or if airway concerns

Nursing Concepts

  1. Cognition
    1. Assess LOC
    2. Assess Pupils
    3. See Neuro Assessment lessons
  2. Intracranial Regulation
    1. Determine possible cause of ↓ LOC
      1. Infection
      2. Acidosis
      3. Stroke
      4. Hypoglycemia
      5. Hypoxia
  3. Clinical Judgment
    1. Applying O2 and giving oral sugar sources can and should be done without provider order
      1. Notify after intervention
    2. IV dextrose requires order – must notify provider if PRN order not available
    3. Call Rapid Response or Code Blue as appropriate

Patient Education

  1. Reassure family of purpose of painful stimuli
  2. Educate patient on importance of orientation questions with each assessment


In this lesson we’re going to talk about the different levels of consciousness. This, plus your pupillary assessment are going to be the staples of your neuro exam. We’ll talk more about the pupillary assessment in the routine neuro assessments lesson.

In order to understand the varying levels of consciousness, we need to know what normal is. So let’s talk about what a normal neuro exam would look like. This is someone who is considered conscious. This would be like you and me. We’re awake, alert, aware of our surroundings. We’re able to respond to stimuli around us and follow commands. If they’re asleep, give them a chance to wake up. If they arouse easily and are able to remain alert, that is normal. Then we’ll ask the patient four questions. “What’s your name?” “Where are we right now?” “What month is it?” and “Why are you here?”. This tells us orientation to person, place, time, and situation. If they get all 4 correct, we say they’re Alert and Oriented times four. Now, not all facilities use situation, so you would just say they’re oriented times 3, and that would still be acceptable.

The next two levels of consciousness are patients who are alert but are NOT oriented. People who are confused can’t answer all of the orientation questions. They might be alert and oriented times 1 or 2, or even 0. They have difficulty following commands and their thought processes tend to be slow. They may even have memory loss. This can be caused by sleep deprivation, which happens a lot in the hospital, or even infection. In fact the number one sign of infection in the elderly is confusion. And remember hypoglycemia can also cause confusion.

The next level down would be delirious. Someone who is delirious is confused and disoriented AND also restless or agitated. They struggle to pay attention to their surroundings and may even experience hallucinations or delusions. I had a patient with ICU delirium once who SWORE there were spiders crawling on the walls. ICU delirium happens because of sleep deprivation and sometimes the number of meds we are giving, patients begin to lose touch with reality. We also see delirium in Alzheimer’s patients when they are sundowning.

The next level would be patients who are only minimally responsive. They are not alert. Patients who are somnolent are extremely sleepy. Somnolent, Sleepy (both start with S). But this is like next-level sleepy – this isn’t you after you pulled an all nighter studying. These patients are hard to keep awake, they just keep falling back asleep. You try to arouse them and they might just mumble at you. This is the point at which we begin to use painful stimuli to try to elicit a response. We want to give them credit for the best response they can give, so we’ll start with maybe nail bed pressure, then we could try a trapezius squeeze, and move on to a sternal rub to see what kind of response we get from the patient. Usually somnolent patients will open their eyes, mumble at you, and maybe swat at you, then they go right back to sleep.

Now, obtunded is a little different. This is someone who might actually be awake, but they’re not alert to their surroundings at all. It’s like the lights are on but no one’s home. Their responses are slowed or the may not respond at all. Sometimes it’s like they’re staring right through you. They may also have some delirium with it. This could be caused by a stroke or by high ammonia levels.

From there, we move down to patients who really aren’t responding at all. Stuporous patients are in a sleep-like state. They aren’t moving around on their own, but they do respond SOME to stimuli. You will see grimacing on their face, and sometimes they’ll pull away from you when you cause a painful stimulus like nailbed pressure or a trapezius squeeze. That’s called withdrawing. Again, we use increasing levels of painful stimuli so we can give them credit for their best response.

And finally we use the term comatose for people who are completely unarousable. They don’t respond to any painful stimuli, even super deep sternal rubs. The other thing we want to assess on these patients is whether they have a gag or cough reflex. We use our yankauer to stick in the back of their throat to try to elicit a gag response. The number one concern here is that this patient might have trouble protecting their own airway, so we need to get help as soon as possible.

Now any of these neuro changes could be attributed to a number of diseases, from cardiac to respiratory to metabolic to neurological. The most important thing is to recognize the change and notify the provider so that we can begin to identify the cause. And if you remember from the cerebral metabolism lecture, the brain is very sensitive to a low O2 and a low glucose level. So check your patient’s SpO2 and blood glucose levels while you wait for the doctor to arrive!

So remember when we assess level of consciousness, we are first assessing whether they’re alert and awake, then we assess their orientation to person, place, time, and situation. So we’d report they’re Alert and Oriented times 1, 2, 3, or 4 or 0 if they’re completely disoriented. Then if they aren’t alert and oriented, we need to assess their response to painful stimuli. So your basic levels are alert and oriented, alert but not oriented, minimally responsive, and unresponsive. Remember that if you note any changes, you need to notify the provider right away.

Make sure you check out the next few lessons to learn about routine and adjunct neuro assessments! Go out and be your best selves today, and, as always, happy nursing!!