In today’s micro lecture, Australian Paramedical College Hon. Snr. Lecturer Sam Willis discusses Head Injury; how it can be either minor or major plus how you’re going to see a lot of it as a Paramedic.
In today’s lecture we’re going to talk about head injury. My name is Sam Willis and I’m the Senior Lecturer for the Australian Paramedical College. Now, head injury can either be minor or major, and as a paramedic, you are going to see a lot of it. Now, think about the typical situations where you’re more likely to see head injury that can be anything from somebody who’s been hit by a motor vehicle, somebody who’s come off of a motorbike, somebody who’s fallen from a height. Maybe it’s an elderly person that’s fallen and hasn’t been able to put their hands out in front of them to stop the fall. Maybe Friday, Saturday night somebody’s been involved in an assault. So, so many different possibilities when it comes to head injury.
Now, the good news is, not all of it is major, but the other side of that is that even the minor injuries actually can look major and you really do have to go through a series of carefully considered steps to be able to identify whether it’s actually minor or major trauma and to try and establish how fast and how slow you actually need to work to be able to take the patient to the next place of treatment, if at all. So, we’re going to talk about head injury and trying to put it into context with paramedic practice.
So, we’re going to start by looking at the layers of the scalp because this really is where it shouldn’t start and end, because scalp injuries really can look actually much more serious than they are. So, that means that if you’re not aware of the fact that scalp injuries in the most part are quite minor, then you really are taking everybody to hospital quickly and it really just cause problems in the system.
We’re going to look at the functions of and purpose of cerebrospinal fluid because it really does play a huge role when it comes to cushioning and supporting the brain and preventing the brain from becoming injured. We’re going to look at a number of different types of head injuries and we’re going to discuss the principles of head injury management. Now, just remember guys, this is a very short lecture in the grand scheme of lectures, so we’re not going to be able to cover everything that you need to know about head injuries, and I don’t think there’s ever an expectation that these lectures ever do because even the top experts are constantly learning all the time.
So, let’s start with a case study then. This is a typical case study that you, one of many case studies that you are going to be faced with as a paramedic. So, you’ve been dispatched to a busy dual carriageway where there are reports of a male who has been hit by a car and is laying motionless in the street. As you pull up on the scene, bystanders looked panicked and approach you stating that the male was hit by a car travelling at least 80 kilometres an hour and sped off down the street. They say that the male was thrown into the air then came to rest where he is now and he hasn’t moved since.
Now, in this scenario, there’s a number of complexities. First and foremost, the people watching this are stressed, and that shows me a good indication as to how injured that person might be. Second there’s an automatic danger of a dual carriageway. Now there are occasions when the traffic has been stopped. Now, that’s going to cause you problems anyway, getting to the scene. Now, fingers crossed there’s a hard shoulder or another lane for you to be able to get to the scene otherwise you’re going to struggle to get there in the first place. What you’ll also find is that motor vehicles will jam up the smaller roads too. So just getting to the scene can be a problem.
Then of course, when you get to the scene and get to the patient, if this person has been thrown in the air, then there’s obviously enough energy to catapult that patient, and if they came to rest where he is now and hasn’t moved since, that can be for one of two reasons. Either they’re unconscious and haven’t been able to move, or they’re conscious and haven’t been able to move because of their injuries. Now, the third option actually is that, they’ve been told not to move by members of the public.
So, again, all of these considerations, with the biggest one being danger, the first thing you would always assess in your primary survey is, are there any dangers to you, your crew mate, your patient, and if you can move them because there’s a danger then move them, but if the dangers have been stopped, in other words, if the traffic has come to a standstill and there’s no danger now, then don’t rush to move this person.
So, we’ve already said that paramedics will attend to many patients who present with head injuries and we’ve given some examples of the typical nature of head injuries. We’ve already said that they can be minor or major, but how do we differentiate between the two? Now, a minor head injury is something that might look bad but actually doesn’t cause an ABC problem. There’s no loss of consciousness, and there’s no major hemorrhage. Whereas major problems are the flip side of that. A head injury that’s caused a possible internal bleed. Now, external bleeds are usually much messier than they look when it comes to scalp wound. So, for example, we’re going to look at the scalp and all the different layers in a moment, but with a major head injury, you’ve got some kind of internal bleed which is recognized by Cushing’s triad, which we’ll talk about in a moment, you might have some kind of loss of consciousness, and you might also have other types of signs of shock as well. These are the types of situations you would be worried about in terms of a major head injury.
And of course, there are fine lines between the minor and major because if you’ve arrived on scene and somebody has been hit by a vehicle or being assaulted from behind and they’re showing signs of concussion, now, concussion is something that should be temporary and should be restored within 24 hours. In other words, there shouldn’t be any long lasting signs after 24 hours. However, if the signs and symptoms have lasted more than 24 hours, that’s a problem. And again, as a paramedic, you will actually be able to recognize whether or not they’re going to last more than 24 hours or not because you’re not going to be around. Paramedics must be able to recognize the severity of head injury and treat it accordingly.
Okay, so let’s move on to our next slide. So, here we can see the layers of the scalp. All you need to know from this slide at this level is that the scalp has got five layers. S-C-A-L-P. You don’t need to know a massive amount about the different types of layers as we can see here, but just understand that on the surface of the skull, you’ve actually got five layers of tissue and it’s not just one layer. Now, beneath the layers of the scalp you then have the skull. You also have the brain and the meninges which is another slide which I’m going to show you in a moment.
Now, the reason you need to know this guys, is because when you go to people with scalp injuries they could have damaged one or all of these layers, and as you can see it’s the connective tissue the second layer that is highly vascular. So if you do see what appears to be serious bleeding, you’ve usually damaged down through this layer here and you’ve damaged this highly vascular layer here. The good news is you still got another three layers before it gets to the skull. So, you need to have that understanding that you’ve only really damaged the two layers. With scalp injuries what you tend to find is, depending on how big the wound is, is that the bleeding tends to go inside the hair and map the hair and it tends to come down the face.
So as the paramedic, it’s your job to first and foremost recognize that there’s five layers to the skull and it’s the second layer that’s got all the circulation, and when you actually move the hair out of the way, so you’re going to need to have your gloves on. And when you actually move all the hair out of the way, what you’ll probably find is the laceration is probably not that big, but it just so happens that you’ve [inaudible 00:08:20] one of the circulations, so having an understanding of the different five layers and it’s the second layer that’s got the circulation gives you an understanding about how serious this actually is. And what you’ll find is the blood that’s all over the face, once you’ve cleaned it off, the patient generally if they haven’t got any other signs or symptoms, has only really got a small wound. Yes, they might need to have it sutured or they might need to have it glued, but you’re generally not having to use blue lines and sirens to get to the hospital with this patient.
Again, this is just another image showing you the same thing. The difference being is here you can clearly see the scalp and then you get to see these are the layers of the brain. Now, what we’ve kind of touched on and started to allude to is that you’ve got the internal and the external injuries. With the external being what we’ve just talked about, the layers of the scalp, but also facial injuries as well. Now, typically the face has its own separate classification because you end up with what’s called Lefort fractures when there’s signs of trauma, but it’s all tend to be classified in the same way because it’s all the same tissue. If you cut here you could pull the whole thing off, but really the scalp is the tissue covering the head.
Then of course you’ve got the internal bleeding which is potentially going to cause raised intracranial pressure. We have these things called Coup and Contrecoup which is the movement of the brain too fast in one way than the other and it can be left to right or it can be forward to backwards, or it could be diagonally, and the typical mechanisms of injury that could cause this include high speed, road traffic collision, or any of the place where there’s excessive acceleration and deceleration forces.
Traumatic brain injury covers a range of different typical signs or symptoms and illnesses and injuries, depending on the location. All it means is there’s an underlying brain injury caused by trauma. So, we’re not going to cover too much of that in this session. Again, concussion, it’s a temporary set of signs and symptoms caused by a movement of the brain within the cranial vault and you end up with things like severe headaches, nausea, vomiting, you can end up with semi conscious states and dizziness as well.
So, let’s talk a little bit about cerebrospinal fluid. As the name suggests, cerebral is the brain, spine is the spine, and fluid. There are generally speaking a number of different functions of cerebrospinal fluid, but first, let’s show you where it is. So, here you have the main flow of cerebrospinal fluid. Notice how it moves into these different spaces all the way around the brain, all the way around the spine, and it acts as a shock absorber and it provides nutrition to the brain and the spinal column. Notice how, this is the skull here on this outer part here. If there were to be movement within the cranium within the skull, you’ve got this amount of movement. In other words, the brain can actually move if you have these excessive forces. There is space to move.
However, if there’s any bleeding that’s a problem because the only thing that should be in this space as you can see is the brain and the CSF, nothing else. So, functions of the CSF include shock absorber, a mechanical buffer, acts as a cushion between the cranium and the brain, acts as a reservoir and regulates the contents of the cranium. As we’ve said with that, the only thing that should be there is the CSF and the brain. Serves as a medium for nutritional exchange, so allows the brain and spinal cord to become nourished, and transports hormones and hormone releasing factors. So, it allows hormones to float around within the fluid. So, these things are normal and natural within the CSF. They don’t take extra space on top, all of these things act within the cerebrospinal fluid.
Now, let’s say for example you have a bleed within the brain and the brain bleeds externally into the space, into the subarachnoid hemorrhage, the subarachnoid, or any of the other spaces within the brain. You could end up with this here. This is an internal bleed that it been actually between the brain itself and the actual cranium. So, this is the skull here, this is the brain as you can see, and in this occasion you’ve got a bleed between the skull and the extradural space. Extra meaning outer.
What happens is, it pushes the brain and squashes the brain and as a result of that it increases the intracranial pressure. Now, this is called Cushing’s triad. With the Cushing’s triad, your blood pressure goes up, your heart rate goes down and you get altered resps. So as you can see here, your blood pressure goes up, so you take a blood pressure [inaudible 00:13:46] raised blood pressure, your heart rate goes down, so bradycardia and altered breathing patterns, and that’s called Cushing’s triad. Typically, you get to see these in patients who are presenting with stroke. So, one way of checking for an intracranial bleed is to do some blood pressure, take the heart rate and look at their respirations.
Now, we’ve mentioned Coup and Contrecoup. This is just what it looks like in an image format. So, here it’s saying the first contact the brain makes is with the back of the skull, but can also work forward. So, for example, if you’ve fallen from height and your head has hit the ground, the impact is going to be here. Therefore, the brain has moved backwards. But likewise, it can be forwards or backwards. It doesn’t actually matter which one hits first, what you’re noticing that you’ve got these two motion, an extension and reflection motion. So extension is this way. Remember when you did your basic life support and you talked about tipping the head backwards, that’s an extension. You extended the airway, you open the airway. Extension and flection.
What you end up with are bruising to these parts of the brain. And for you guys to really understand the types of signs or symptoms you will get, really does depend on the mechanisms of injury. For example, if you were to bruise this part and this part, you will expect to have differences in your personality and your balance. But of course, having an understanding of the different parts of the brain will give you an idea of the types of signs and symptoms depending on the impact.
Again, traumatic brain injury is a collective term for any type of injury to the brain caused by trauma. This is just a nice little pie chart that shows you the typical types. This was in Australia between 2012 and 2015, and you’ve got motor vehicle causes, motorcycle, cyclists, pedestrians, other transport related, low falls, high falls and other. That really just gives you an idea as a paramedic as to the types of cases you will be going to as a paramedic.
Now, here we’ve mixed two types of fractures. One is the skull fracture. One is the facial fracture. So two different types of fractures, but I’ve placed them into the same slides. So, these facial fractures are called Lefort fractures. Lefort I is when you have a fracture of the maxilla that goes up to the nose and down here. Now the problem with this type of injury is that it can actually dislodge and cause a lot of pain, possibly airway problems. Even worse is Lefort II which is an extension of this, so notice how it starts and ends in the same place but it goes up through the eyeballs through the orbital regions. Again, causing possible heavy bleedings into the eyes, possible dislodge of the eyes, possible cerebrospinal fluid leaks, and then Lefort III, this origin and ending has basically moved up and gone across the orbits. Again, you’re more likely to get cerebrospinal fluid leak with the Lefort III than with the other two, and of course as you know with cerebrospinal fluid you end up with the leaking of cerebrospinal fluid, you end up a bruised eyes, and battle signs behind the ears as well.
Then of course you’ve got these different types of skull fracture. Now unfortunately with all of these types of injuries, you can’t actually see the fractures without an X-ray but what you can see is a patient in a lot of pain, they might have reduced levels of consciousness, there might be cerebrospinal fluid and other signs and symptoms and it’s your job to treat those things and keep the airway clear.
Now, we’ve talked a little bit about scalp injuries. Just notice how the scalp has got all these different circulations. You’ve got venous circulation carrying blood back to the heart, and arterial circulation that carries blood to the scalp itself, and of course, we’ve mentioned that it’s the second layer that has got all the bleeding, possibly some bleeding has occurred here but now stopped, which is great. For this patient it’s your job to try and assess mechanisms of injury, do you need to perform C-Spine Immobilization, you certainly need to try and cover this for the purposes of infection. Some paramedics might even say, “Well, look, it’s actually stopped bleeding and it’s healed nicely, I’m not going to cover it because it creates a breeding ground for bacteria.”
But if there was oozing of blood or it was opened in any way, that wouldn’t be a question [inaudible 00:18:38] cover it. What you have got here is that is a particularly difficult type of injury to cover. I mean, I would use some kind of medline dressing and I would just take over the top. Remember that the emergency department is going to take the medline dressing off and take a look at it any way just to work out if it needs glue in or if it needs suturing and of course, on top of looking at the head’s injury, you need to be looking at any type of C-Spine injury and ABC problems.
Now, the treatment priorities always come down to primary survey first. Some head injuries will cause airway complications and therefore you need to managing ABCs. On some occasions, your patient needs to be knocked unconscious using a process called rapid sequence intubation and have their airway managed by intubation. Don’t miss C-Spine management because you’re distracted by a head injury, cover and keep the area clean, manage the pain to the best of your abilities using the drugs that you have in your scope. Undertake a full history including asking the patient to tell you what happened. And what I’d like to add into here is to do a mini neurological assessment. Do a GCS, do an MSC times four, and do your full primary survey. Establish any loss of consciousness which will help identify concussion or more serious underlying injury. Reassess, reassess, reassess continuously.
Okay, in the session, we’ve looked at the layers of the scalp. We’ve talked about CSF. We’ve looked at different types of head injuries and provided an overview of treatment management.