In this video, we are going to review the glasgow coma scale, or GCS. If you already know about the GCS and want to review how to calculate it for the OT Boards, click the timestamp link below to jump right ahead.
Healthcare workers frequently use the GCS as a scoring tool to assess for level of consciousness.
When I was an EMT, I used the GCS with every patient and in documentation to communicate with the healthcare team such as nurses and doctors. In reality, in the field you don’t really need to remember how to calculate every section because you will have charts or you can use calculators to get the score.
While occupational therapists do not directly calculate GCS for patients, if you are working with the adult population, you are likely to encounter GCS in your day to day work. For example, in the hospital in acute care, occupational therapists may read a patient’s medical history and find the GCS score reported by EMTs and paramedics for a medical emergency or for trauma. Knowing what the score was can provide some insight into how impaired the patient was prior to admission to the hospital.
Unfortunately, you will have to know to calculate GCS during your OT board exam and know it by heart. The OT Board exam may ask you about GCS, either to interpret the GCS score or to calculate the GCS itself.
Since you will get a whiteboard or piece of paper, I recommend that you write out the GCS and calculate the score visually instead of mentally in your head when you are under the stress of taking the exam. While it may take some practice to learn how to calculate GCS, it is not a question you should be missing on the exam.
A GCS score is comprised of three areas – eye movement, verbal response, and motor function. A score is assigned to the performance of each to get the total. While the GCS has become widely used, it is not very user friendly. The GCS has a confusing score range and ranges from 3 to 15. Therefore, the lowest score you can get for a patient is 3. Instead of the lowest score for each section, eyes, verbal, and motor being 0, it is 1. Therefore, 1 + 1 + 1 = 3 for the lowest score. How do you get 15 then for a normal functioning adult like you and me?
The mnemonic to remember is 4 eyes, like the name you call someone who wears glasses. Interesting fact, 4 eyes is a nursing term for how and when they can document a patient’s skin integrity for pressure sores. So for the eyes part of GCS, you can score from 1, lowest, to 4, highest.
The second way I remember how to add up the GCS is 4, 5, 6. 4 for eye response. 5 for verbal response. 6 for motor response. Really, the GCS is an assessment of 3 different motor and sensory systems. Therefore, a person calculating a GCS needs to interact with the patient to see their eyes, verbal, and motor response. What’s nice about the GCS is your interaction with the patient is quick to allow you to get a GCS score. Calculating the score itself is a little trickier. So adding 4 + 5 + 6 gives your 15.
How do we interpret the scores?
A score of 13-15 would be mild brain injury. You and I are in this score range.
A score of 9-12 would be moderate brain injury.
If you have a score of 8 or less, the person would likely be unconscious or in a coma.
Let’s calculate GCS.
We start with eye response.
Eyes can be spontaneously open, like how I have them open. That’s a 4.
However, they can open to a stimuli such as you calling their name. That would be a 3.
Keep in mind that a person sleeping is not considered a deficit, so they would still be 4 because when they are awake, their eyes are likely open.
What would be a 2? The person does not respond to your voice and you would have to pinch them for their eyes to open. This is considered a painful stimuli. Other things to introduce painful stimuli can be pinching a nailbed or doing a sternal rub.
Remember how 1 is our lowest score? That would mean that no matter what you do, their eyes won’t open and you would have to pry them open to look at them with a penlight for example.
If you introduce a painful stimuli such as pinch, don’t forget how they respond because it is used later in the motor response section, which is from 1 to 6, remember 4, 5, 6.
Although GCS is usually calculated in the order from eye response, then verbal response, and finally motor response, it would make more sense to explain motor response next, since we talked about the painful stimuli introduced if the person did have their eyes open and get a score of 4 or did not respond to your voice to get a score of 3 and would be a 2 for opening their eyes to a painful stimuli.
Motor response is how someone reacts to directions, and if they don’t to a painful stimuli. If you ask a person to raise their hand for example and they do, that would be a 6. Remember 4, 5, 6. Let’s say you had to pinch someone. The normal response would be to pull their hand away. That’s how you get a 5 for motor. A 4 would be responding in some way or another, but as directly such as pulling your arm away. Maybe they may move a little or make a face. When someone becomes even more impaired such as being comatose, they demonstrate specific patterns. This would be the next lower scores of 3 and 2. Just so you know, a score of 1 for motor would be no response and they just lay still. To make sense of 3 and 2 for motor we have to talk about decorticate and decerebrate posturing. Here are some pictures of each. You should also know how their extremities look like because the board may not necessarily mention decorticate or decerebrate.
One way I remember what they look like is imagining someone on their death bed. Before they die, they may be praying, therefore their elbows are flexed and shoulders internally rotated. This is decorticate posturing and would give you a score of 3 for motor response. For decerebrate posturing, you know those cartoons of someone on their deathbed and then their soul elevates towards heaven. This is what I imagine decerebrate to look like. They would be floating in the air and therefore their arms are to their side and extended because they would be weightless. That’s how you get a 2 for motor response. And obviously if they are dead or very comatose, they would have no response and you would get a 1 for motor response. I hope this makes sense, but it’s how I remember decorticate vs decerebrate and how their upper extremities look like.
The last score to calculate is verbal response. This is done by asking the A&O questions to see if someone is alert and oriented. What is your name? What city are we in right now? What year is it today? What happened to you to call 911? So 4,5,6, the most we can get is 5 for a verbal response. They would have to answer all your A&O questions correctly to get a 5. If they get at least 1 wrong, they would be a 4. If someone is not alert and oriented, for example, they say that we are in outer space, you would give them a 4. A 3 would be if someone responded inappropriately to your questions. For example, if you ask someone what year is it and they say something random like donald trump or they are not able to answer any of your A&O questions. I was taught to ask 4 A&O questions with the 4th one being to situation, such as what happened to you to call 911. Some nurses and doctors ask only 3 A&O questions, which is why you may see A&Ox3 or A&O4. This can be confusing because if you see A&Ox3, it does not necessarily mean that they got the 4th question wrong for situation, they were just not asked the 4th question. You’ll also see people ask other things like who is our president and things like that, but I was taught to always ask about the pertinent situation at hand. So a verbal response for 3 is if the person says something random. How would you get 2? That’s if they make sounds but they do not make sense. Someone who is having a stroke may produce sounds that is a 2. Last we have 1, if they cannot speak at all.
So putting this all together, we get the total scores for eye response, verbal response, and motor response. Another way to remember the 4,5,6 is starting with the top of your head and using your body as a landmark to remember the order. You have 4 eyes. Next you have your mouth which is below your eyes so that’s 5. Last you move your arms for motor response, which is below your mouth for the possible total of 6.
The OTDUDE website has a calculator that can quickly calculate GCS. I recommend that you play around with it to help understand how each eye, verbal, and motor add up to get your total GCS scores. This GCS calculator is nice because you can see in realtime how each section for eye, verbal, and motor response affects the total score. The calculator also provides the interpretation for mild, moderate, and severe brain injury.
Hope this video helps you understand GCS a little better. Even if you have a good understanding of what GCS is, I highly recommend calculating a score from the information given for each section.