 Hi and welcome to Nursing School Explained and this video on cranial nerves. Now the neurologic assessment in general can be a little bit anxiety inducing because there is a lot to memorize. So with this video I'm hoping to give you little tidbits of information that will help you first of all with an acronym on how to memorize these cranial nerves and then second of all how to make sense of them if they are sensory or motor control nerves and then thirdly also hopefully by dissecting the names of the cranial nerves to give you a little bit more of information on how you can memorize them easier. So to start with here's an acronym that I learned in nursing school that I found very helpful over the years to remember the correct order of these cranial nerves and that acronym is kind of silly but it works O-O-O to touch and feel very green vegetables ah-ha. So the first letter of the the sentence of each word represents the cranial nerves all 12 of them. So if we look at that O-O-O or factory optic oculomotor to touch and feel trochlear, trigeminal, abducens, spacial and then here very green vegetables ah-ha which is vestibular cochlear or acoustic is also what it's called but you really have to memorize the V here for the vegetables and then glasopharyngeal, vagus, accessory which is also called spinal accessory as well as hypoglossal. Okay and then over here I have made a little legend S for sensory, M for motor control and B for both. As you can see we have three cranial nerves that control both and all the other ones just really logically think about it when there is sensory involved it's some sort of a sensation so is it either the patient can feel something, smell something, see something, taste something and then when it's motor it always has to do with movement so are they moving their tongue their eyes their cheeks any part of their face of their cranium that we can assess so that would be the motor motor nerves and then some nerves actually can do both and those are the trigeminal, facial and glasopharyngeal. So let's go over those here. So number one cranial nerve is olfactory which assesses the patient's sense of smell. Many times in the clinical setting or in the acute care setting it's not really done because there's just not time and it's not really that important but it's important to know how to do it in case it is required of you in the clinical setting so you can take anything that you find in the hospital to help assess the patient's sense of smell I would not go with an alcohol wipe because that can be kind of very shocking to the patient's nostrils if you've ever smelled that closely. Toothpaste typically works well mouthwash or if you have anything else like from a food tray that would maybe be cinnamon or something like that that'll work and you would always ask the patient to close their eyes and then occlude one nostril have them smell whatever you it is it is that you're using and then the same on the other one and you're done with your olfactory assessment the sense of smell. Number two optic optic nerve this assesses the visual acuity as well as the visual fields. Visual acuity is usually something where you stand 20 feet away and you look at the snarling chart and see whatever line the patient can read there are certain snarling charts that are to be used just in front of the patient and you hold them 14 feet out it has the same letters as the snarling chart has and the same legend as to how to identify the patient's vision because it might not be feasible for you to measure exactly 20 feet in the hospital setting if the patient is bed bound. So the visual acuity as well as the visual field and that means the peripheral vision and so if we look at our patient here we want to assess the peripheral vision from different angles as we're coming towards their face and so you're going to ask the patient to look directly at the tip of your nose you're going to use some object either a pen or maybe move use your two moving fingers and you're going to come from different angles and ask the patient while they look straight ahead when they can see this object to assess the peripheral vision and it should really be a pretty broad sense of vision you can try it on yourself almost like a halo around the patient that is just a little bit in front of their face which is where their normal visual acuity should visual field should be. So this was cranial nerve number one and two or factory and optic both sensory nerves only now our ocular motor cranial nerve number three motor like the name suggests has is a motor nerve so it has to do with movement so we want to assess the patient's are extra ocular movement EOM and keep in mind I have made asterisks is here for cranial nerve three four and six ocular motor trochlear as well as abducens because all three of them assess extra ocular movement therefore all three are motor nerves but they just move the eyeball in different directions so for ocular motor number three it's the eye movement up and also Perla so pupillary response to light and accommodation for trochlear number four it's the extra ocular movement down in the visual field as well as towards the nose and then abducens is the eye movement laterally out now we're not going to ask the patient to move their eyeballs out towards their ears it's going to be very hard to do so what we're going to do to assess cranial nerves three four and six is to assess their extra ocular movement by kind of making a star pattern in front of their face so you can just hold a pen in front of their face make sure it's not too close so they don't feel like threatened here maybe a foot and a half or so in front of them and ask them to focus on the pen and just with their eyes follow your pen that you can hold in front of them in the star-shaped pattern and while they are doing that you're going to observe their eyeballs to make sure that they're moving equally and that one is not delayed in movement or not moving at all and assess their extra ocular movement so just with one test we can knock out cranial nerve three four and six now then trideminal nerve is the first one or that has both sensory as well as motor control and so the trideminal nerve has three branches trideminal three branches and if we look at the patient's patient's face the three branches on each side are on the forehead the cheek and the jaw I like to show it in the clinical setting like this where you have three branches forehead cheek and jaw and so we have to assess their sensation their sensory response in this these three locations and so what you can do is take a cotton tip applicator where the cotton is on one side and the wooden stick is on the other so one of them would be dull the cotton and the other the wood end would be the sharp you would have to tell the patient first what it feels like each side and then touch them on each of those locations on both sides and see if they can correctly identify sharp and dull and that is the sensory of the trideminal nerve now for the motor response of the trideminal nerve you're going to ask them to open and close their mouth and then close their jaw and palpate the muscles make sure there is no tremors or that there's no weakness there as well as the corneal reflex now corneal reflex can kind of be scary for patients because it is the reflex that closes the eye when the eyeball feels like threatened when there's something coming at it now we want to be very careful that we don't harm the patient's eye so many times what you can do you can take a syringe and just put a little bit of air in there and just blow the air into the patients from the side so the patient's eyeball and they'll close their eye the other thing you can do is gently grab a cotton ball and come at them and they will close their eyeball in response of the eyelid trying to protect their eye so that's the corneal reflex it's pretty quick but make sure that you're very careful especially if you're suspecting that maybe that corneal reflex is not intact because you don't want to you know come at the patient with with an object even if it's just a cotton ball and they their reflex is not intact and then you just poke them in the eye with hopefully just a cotton ball but again maybe the air option with the syringes a little bit easier one so that was cranial nerve number five we've already talked about abducens number six for extra ocular movement number seven is facial and again here it has both sensory and motor innervation so for sensory for facial it does our sense of taste sweet and salty so you could take sugar and salt and see if they can taste it for a motor response we want to look at their facial symmetry this is the one that we always think about when assessing a patient for a stroke so we're going to ask them to smile frown puff their cheeks and then at the same time you can have them puff their cheeks and say hold the air in the in your cheeks and don't let me press them in making sure that the muscles there are intact and then close their eyes real tight and then you can try and open them so those will be the motor response of the facial nerve sensory as well as motor response here and then for number eight it's a it's a mouthful vestibular cochlear and just think about it vestibular has to do with your balance and cochlear is that little piece in your ear that helps you with your balance the other word for it is acoustic which acoustic you can think of has to do with hearing so either way you can remember the ear and the sense of hearing but the V vestibular cochlear just works a little bit better with the acronym so just keep that in mind otherwise the a you might get stumped up if you looking for the a but it's actually the V that's our vegetables here that's our very important green vegetables so anyhow by assessing the patient's hearing usually if you just talk into them you can kind of know that they understand you maybe one ear is not as good as the other one in perception so you could just go to the side of the patient whisper something in the ear like one two three and then have them repeat what they hear back to you and that's very easily done one side and then the other and you assess the patient's hearing then for pay for cranial nerves number nine and ten is glasopharyngeal and vagus and glasopharyngeal keep in mind that glasso has to do with the tongue and pharyngeal has to do with the fairings and the vagus nerve is the one that is mostly in charge of the parasympathetic nervous system that slows everything down so but we assess these two together and if you think about glasopharyngeal so tongue and pharynx we're gonna it's gonna have to do with assessing the back of their mouth as well their fairings and their tongue so what we're gonna do here this is the other side of the taste for sensory sour and bitter in comparison to sweet and salty for the facial nerve and then for motor we're going to ask them open your mouth say ah as they say ah we observe with your pen light you observe the rise of the uvula in the soft palate in the back of the throat and then check their gag or swallow reflex if the patient can swallow if you've already seen them drink a sip of water you've already assessed their swallow reflex there's no need to stick a tongue blade back there make them gag although it's sometimes important to do that especially if you may be thinking that their swallow ability is not up to par to do a evaluation of the gag reflex which would require a tongue blade so you would put the tongue blade in their mouth move the tongue down and then very gently touch the back of their throat next to the uvula and then see if they have a gag reflex by again the soft palate and the uvula rising so the and that's both cranial nerves number nine and ten glasopharyngeal as well as vagus and the keep in mind you the glasopharyngeal so we want to have the tongue and the pharynx move so that's a sense sensory as well as motor because the sensation is the taste but the vagus is only a sensory nerve which has to do with the taste here and then the spinal nerve number 11 is the spinal or accessory so I put the spinal in parentheses here accessory keep think about it this week the cranium and then the accessory as the shoulders because it's not really the cranium anymore for the cranial nerves so it's the accessory muscle to the cranium which assesses the shoulder shrug as well as the patient's ability to turn their head left and right so here we want to have them shrug their shoulders but we want to place our hands on top of the patient's shoulders and as they rise and we want to assess to make sure that the strength is equal as we always do check for equality and then turn head against resistance so you can just gently place your hand on the patient's cheek and ask them to press to one side and again you're going to feel for equality of that head movement last but not least we have the hypo glossal hypo low or below glossal the tongue so again this has to do with the tongue movement here and again this is a motor nerve just like the spinal accessory with the movement so for the hypo glossal we're going to ask the patient to stick their tongue out and then move it left and right and as they do that we observe for tremors and to see if the tongue as it comes out is at the midline or if it deviates to one side or the other so it looks like this stick out your tongue move it left and right very simple movement so if you think about it first of all in summary I think this acronym here is very helpful it's helped me over the years and even if I don't think about cranial nerves for several months or years I just think about the acronym and it'll all come back to me and then if you just think about what this tells you so trigeminal has three branches to know about the three sides of the face or glossopharyngeal has to do with the tongue and the pharynge so you kind of already know the general area that you need to assess and then you're going to know what it is that you need to do and then M for motor anything that moves and then sensory is where we assess a sense whether that's vision hearing smell taste or a sensation so all of those so thanks for watching this video on the cranial nerves also check out my other video that I have that actually where I demonstrate the cranial nerve assessment on an actual patient and also check out the other videos in my physical assessment playlist and I see you soon right here on nursing school explain thanks for watching