The fibrinolytics have roughly 6% risk of causing a cerebral hemorrhage even if the diagnosis is correct and there is no bleeding to start with. Unfortunately their benefit is... usually less dramatic, according to the literature (with the initial NINDS study showing no benefit at all at 24 hours, with a change in the primary outcome to highlight the small benefit found at 30d).

A CNS hemorrhage can present similarly, but giving these meds would be a death sentence in this case.

I'm not sure I follow, does this imply fibrinolytics are dangerous drugs by default for the elderly population that tends to get strokes? Are they just dangerous in general?

>with a change in the primary outcome to highlight the small benefit found at 30d

So does that mean "time is brain" is a bit exaggerated then, if the benefits are small?

Fibrinolytics are indeed risky agents to use as they are non-selective in where clots are lysed. To give you a perspective, an injury from a fall from the initial stroke event is likely to re-bleed once fibrinolytics are administered. Patients sometimes bleed around the IV site when the med is running.

These meds need be given within 3-6 hours of stroke onset, depending on who you ask and what heroics you want to accomplish. After the six hour mark, you’re facing the same risks of disability from an iatrogenic bleed versus little gain from therapy because hypoxic tissue is dead at that point.

However, before that window closes, there is significant benefit in doing something versus nothing in stroke. It’s great when the use of the agent results in no deficits. The same can be said when the results are only limited deficits (i.e. use of a cane) versus a wheelchair or admission to long-term care.

> I'm not sure I follow, does this imply fibrinolytics are dangerous drugs by default for the elderly population that tends to get strokes? Are they just dangerous in general?

Dangerous in general, especially for patients with acute stroke. Thankfully the risk of an intracranial bleed is much lower for patients without a stroke (~1% IIRC), so if you get the diagnosis wrong (as there are many mimics) at least the risk isn't as high.

> So does that mean "time is brain" is a bit exaggerated then, if the benefits are small?

¯\_(ツ)_/¯ -- my impression is that the "time is brain" is emphasizing that "earlier is better," which is absolutely the case. Unfortunately, better is not always "good."

Thankfully, for massive strokes, we now have much more effective options (which are generally performed along with tPA). Unfortunately these options require highly trained subspecialists that my be practically unavailable to rural hospitals.

If the patient is having a hemorrhagic stroke, fibrinolytics could cause catastrophic bleeding. As soon as you’ve excluded hemorrhagic stroke (and other hard contraindications), you give fibrinolytics ASAP if you suspect an ischemic stroke.

The same symptoms can be caused by either a blood clot OR by hemorrhage in the brain. If you give a patient with a hemorrhage fibrinolytics, you killed him. That’s why you need the CT first: to rule out bleeding.