Neurogenic Shock: Introduction (Nursing)

00:00 Hi, I'm Professor Lawes. And in this video series, we're going to look closer at Neurogenic Shock.

00:06 They've got several main types of shock: Cardiogenic, hypovolemic, anaphylactic, septic, and neurogenic.

00:15 And that's the one we're focusing on in this portion of the series, neurogenic.

00:20 Now, just to give you a heads up, we talked about the stages of shock.

00:24 Go into more detail in the hypovolemic shock video series.

00:28 So, I'm just going to show you what is different in Neurogenic shock in this video series.

00:34 Now, let's look at the causes of neurogenic shock.

00:38 Now, this will be familiar to you.

00:40 You've got a vertebral column, and within that column, it's meant to protect your spinal cord.

00:45 Now, neurogenic shock can last up to 6 weeks.

00:49 It can last quite a while with this type of injury.

00:53 If a patient has a spinal cord injury, we're usually talking about above T6.

00:58 This is what you might experience with them.

01:01 So, neurogenic shock starts within 30 minutes after a spinal cord injury.

01:06 But keep in mind, it can last up to six weeks.

01:09 So if you're caring for a patient who's in neurogenic shock, what should you expect? Well, we can't really talk about that until we go back and do just a quick review of the central nervous system.

01:19 Now, you've got the autonomic nervous system that has two branches, the parasympathetic nervous system and the sympathetic nervous system.

01:28 Do you remember the difference between the two? Well, this is a great example the artists made for you.

01:33 The sympathetic nervous system is like pushing your foot down on the gas pedal.

01:37 Everything goes faster.

01:39 You breathe faster, your heart rate goes faster, or beat stronger.

01:42 That's the sympathetic nervous system.

01:44 Now, what's gonna happen to my blood pressure and the sympathetic nervous system? With my heart beating faster, my blood pressure is going to go up.

01:52 So that's what you will see in the sympathetic nervous system.

01:56 But move your foot over to the brake.

01:59 What happens to the car? It slows down.

02:03 And this is the action of the parasympathetic nervous system.

02:06 So, let's break down what neurogenic shock is.

02:09 Because neurogenic shock is a combination of both primary and secondary injuries that lead to the loss of sympathetic tone.

02:18 Now, why did I slow down so much like that? Because I want you to keep in mind, what could possibly be going on, if I lose my sympathetic tone, that means I can't make a heartbeat faster.

02:30 I can't constrict my vessels to raise my blood pressure.

02:34 So, if I lost that tone, then the parasympathetic system is going to take over.

02:39 It's unopposed, we say.

02:41 So, in neurogenic shock, you lose sympathetic tone, and it's unopposed. So the parasympathetic goes crazy.

02:51 And that's driven by the vagus nerve.

02:53 So patients have instability and blood pressure, heart rate and temperature regulation.

02:59 So, neurogenic shock, three classic signs: instability of blood pressure, heart rate, and temperature regulation.

03:06 Now, when does it start? Within 30 minutes of the injury.

03:10 How long can it last? Wow, up to six weeks.

03:14 So think about what it feels like for your patient to experience that.

03:17 And let's break it down again, and look at the vessels.

03:20 Remember, the sympathetic nervous system causes vasoconstriction.

03:24 But since an neurogenic shock, you've lost that control.

03:29 You've lost that tone.

03:30 So, the parasympathetic is what causes that vasodilation.

03:34 But if I'm in neurogenic shock, from a spinal cord injury, I'm not able to have that vasoconstriction response.

03:41 So, I end up with massive vasodilation.

03:44 Now, what will that do to my blood pressure? It's going to lower it.

03:49 If I was vasoconstricted, more blood would be returning to the heart.

03:53 But with vasodilation, it's going to hang out in the periphery.

03:58 And remember, when more blood hangs out in the periphery, less blood is coming back to the heart.

04:05 So what happens to my stroke volume? Well, more blood is hanging out in the periphery.

04:10 So less blood is coming back to the heart, which is why my stroke volume is decreased, and my cardiac output is decreased.

04:18 Now, why is all that blood staying out in the periphery? Because I've lost my sympathetic nervous system tone, and the parasympathetic system is running unopposed.

04:29 So that's why everything is vesodilated and stays out in that system.