Brainstorming

I want to talk about Paroxysmal Sympathetic Hyperactivity (PSH), or brainstorming as it’s sometimes called. This is something we see not uncommonly in neurocritical care, but I feel like it’s often misunderstood. I sometimes hear, “I think they’re brainstorming,” thrown around as a possible explanation to any number of symptoms in a patient with any kind of brain injury. But, not so fast. PSH has specific ways that it presents and is much less common in stroke and anoxic injuries than in TBI. So, let’s don’t be so quick to write those symptoms off.

TBI is the most common condition leading to PSH, with 80% of PSH cases happening in TBI patients. 10% in anoxic injury and 5% each in stroke and “other.” There is also no definitive test for PSH, so it’s largely a diagnosis of exclusion. the other thing to keep in mind is that PSH correlates at least somewhat with the degree of brain injury. So, if you have a patient with a relatively minor ICH but symptoms suggestive of severe acute PSH, that deserves some further investigation.

In the ICU, we mainly use 2 strategies to deal with PSH, stopping the episodes and preventing further ones. In terms of stopping or controlling episodes, propofol, opioids, and benzos are the mainstay. If you have a patient with severe storming, its likely that they’re intubated, so a propofol infusion can help to control the episodes along with providing sedation. Morphine is the commonly used opioid for stopping a storm, but fentanyl may work faster.

In addition to stopping storms, you want to prevent future ones. Propranolol is my first go to drug here, but you have to be careful in people with reasons to avoid beta-blockade(bradycardia, hypotension, heart blocks). Gabapentin can also be helpful, with the added benefit of helping in patients with neuropathic pain. If you don’t need to big gun sedation of propofol to stop a storm, dexmedetomidine can provide some lighter sedation and serve to prevent storms.

Bottom line, the most important take home message is, be sure that you’ve excluded other pathologies before settling in on PSH as the cause of your problems. Josh Farkas has a great article over at the IBCC on PSH. Check it out here.