These go to 11

One of the ways you can diagnose a subarachnoid hemorrhage is by way of a Lumbar Puncture (LP in medical talk - not Long Playing - that's music talk). This is more commonly known as "bleeding in the brain"

Now, this type of malady is a serious medical emergency and can lead to death (the ultimate seriousness) or severe disability.

Colloquially, an LP, is known as a spinal tap.