Monro-kellie Doctrine

00:00 What is this? Go on, any one of you, everybody knows the answer.

00:11 The cranial cavity.

00:15 Yes, very good.

00:23 Yeah, they had to compensate.

00:24 So, these three things are constant, brain, blood and CSF.

00:28 So, if there is edema, and the brain expands cerebral edema, then you're cerebral perfusion pressure will drop and that will lead to further compromise.

00:42 So Monro-Kellie principle is the cranial cavity is enclosed space which does not have any leeway to expand, leeway to compensate for an altered physiology, okay? So the three components of brain, blood, cerebral fluid, if one way to increase in size, or there was an addition of a mass then the other content has to be displaced to keep the ICP constant.

01:14 Okay? What's a normal ICP? Very good.

01:19 Result of raised ICP.

01:21 This is where you have the array and then you have cerebral herniation, respiratory failure and death.

01:27 Okay, management of raised ICP.

01:30 There are few things which can be asked but then you are just know what are the commonly used ones.

01:57 Okay, the question we have seen is related to steroids.

02:01 What's the role of steroids in head injury? Would you give steroids to reduce cerebral edema? No.

02:07 Okay, that's only if in cerebral tumors, it's effective but in trauma situation, steroids do not have a role.

02:16 CPP calculated, how do you measure cerebral perfusion pressure? ICP.

02:24 Yeah.

02:26 (Mean arterial pressure) - (ICP).

02:28 Okay, that's your cerebral perfusion pressure.

02:31 Cushing reflex is? Hypertension and bradycardia.

02:39 Okay.

02:40 So, it's a mixed vagal and sympathetic stimulation in response to an elevated ICP, leading to hypertension, to ensure increased cerebral perfusion pressure, that leads to bradycardia because vagal stimulation.

02:57 Yeah, same for neurogenic shock for, yeah.

03:08 Okay, do you know the answer to that? Okay.

03:38 This is from the NICE guidelines.

03:42 May be persistent headache.

03:44 I think it was that it mean, yeah.

03:46 Not simple headache.

03:47 Okay, okay.