We're back at the Internet Book of Critical Care podcast. I'm here with Adam again. We're talking about meningitis and encephalitis today.

This is a bohemic. This is a cornerstone of critical care and really important for all of us to have dialed in.

So today we're going to cover in what patient populations should you suspect a

CNS infection. Then we're going to cover the management of that stuporous or comatose patient. What

antimicrobials or antiviral concoction you're going to throw at them and then how you're going to

interpret that CSF gold that takes you so much work to get. So Josh, why don't you start it off?

When should I suspect a CNS infection?

So first, let me take a step back and say that is an intensivist, this is actually easier

for me than it would be for like a frontline ED doc because by the time I'm getting called,

something is going pretty badly.

So they've already been screened in a way for meningitis and cephalitis. So this discussion may not apply perfectly for someone who walks into the emergency

department and is totally fine, but has a headache. I don't know, Josh. I think that diagnostic

approach is pretty difficult in the seizing individual who's intubated with that perpuretic rash.

That's pretty difficult diagnosis to make. It's incredibly subtle. Yeah. With that caveat, it's difficult. And this is something that

continually tortures us, I'll admit a patient. And then, you know, the next attending who comes

on will be like, well, did you get an LP? And I'm like, well, no, I didn't get an LP. So how are we

supposed to approach this? I think in general, you should probably think about a CNS infection for folks who have some evidence of

infection, fever, hypothermia, left shift, et cetera, et cetera, something going on neurologically,

altered mental status, nuclear rigidity, photophobia, headache, seizures, some sort of neurologic

badness, and no other alternative explanation that's accounting for everything else. And that's

pretty broad, unfortunately. And as you said, there's no single finding that's completely reliable. That nukeal rigidity we all depend on is only

80% sensitive. And Kernigs, that's all out there in the universe, but pretty useless tests. So when

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