April 11, 2019

The shiny new toy in stroke treatment is endovascular therapy.  There have now been 12 randomized controlled trials (RCTs) on endovascular stroke therapy (EST), with eight of the last nine showing positive results – stunningly positive.  This flood of positive trials has led to new guidelines from the American Heart Association (AHA) and American Stroke Association (ASA)that extend the treatment window potentially as far out as 24 hours after last known well, and has spawned a movement to completely overhaul how we deliver care for patients with acute ischemic stroke (AIS). With all of the enthusiasm for EST, it is important to review the evolution of this new approach, to review and critique the evidence, and to evaluate what this means in clinical practice.

April 1, 2019

Background: No matter which side of the debate you sit on in regard to systemic thrombolysis in acute ischemic stroke (AIS), there is one truth: systems have undergone major changes to ensure tPA is offered to patients in the ≤4.5-hour window.  The debate surrounding tPA in AIS lies in the equipoise surrounding benefits while there are very real harms.  Advocates of tPA in AIS hang on to two trials that have never been replicated (i.e. NINDS and ECASS-III), and both have major methodological issues. Skeptics of tPA in AIS appropriately argue that there are 11 other randomized clinical trials which have shown almost no benefit, but come at the cost of early increased early mortality and symptomatic intracranial hemorrhage (sICH) (Nice breakdown of individual trials of thrombolysis in stroke can be found at First10EM).  Now there is a push to extend the window of tPA out to 9 hours in AIS with newer imaging modalities such as MRI diffusion-weighted studies in patients with unknown onset of symptoms. The push for this stems from the fact that patients with a visible ischemic lesion on diffusion-weighted imaging, combined with the absence of a clearly visible hyperintense signal in the same region on fluid-attenuated inversion recovery (FLAIR) is predictive of symptom onset within 4.5 hours before imaging.

October 24, 2018

Background: Headache is a common presentation to the emergency department  (ED) accounting for 2% of all visits [1].  Of the patients that present with headache,1 – 3% will be due to a subarachnoid hemorrhage (SAH) [1]. SAH is a true diagnostic dilemma as delays in diagnosis can lead to significant morbidity and mortality. Further complicating matters, almost half of patients will be alert and neurologically intact at first presentation [3].  Non-Contrast Head CT (NCHCT) is very sensitive when performed soon after headache. However, we don’t want to order unnecessary NCHCTs as that increase cost and radiation exposure. Invasive testing such as lumbar puncture, which in itself can be a painful procedure, can also cause headache.  The Ottawa SAH Clinical Decision Rule was designed to help facilitate the identification of SAH in alert, neurologically intact adults presenting to the ED with acute, non-traumatic headache, while minimizing expensive and invasive over testing.  This post will serve as a review of the current literature in the derivation and validation of the Ottawa SAH Clinical Decision Rule.

September 6, 2018

Background: Despite serious concerns about the role of alteplase in the management of acute ischemic stroke including, but not limited to, significant conflicts of interest, unbalanced baseline patient characteristics, systematic devaluation of contrary data, lack of reproduced benefit and low fragility index, it remains standard care for patients presenting with symptoms of acute ischemic stroke within 3 (or 4.5 depending on system) hours of onset of symptoms. Though the NINDS studies only showed benefit in a specific subgroup of patients, subsequent work has endeavored to expand the target group in a classic example of indication creep. Patients with minor CVA (NIHSS < 5 without disabling features or, essentially mRS 0-1) represent one such subgroup in which alteplase is often not employed due mainly in part to the perception of minimal benefit with continued potential for harm (i.e. anaphylaxis, intracranial hemorrhage). Alteplase supporters argue that minor stroke patients should still get the drug as it not only may reduce symptoms but can also prevent deterioration. The evidence for this viewpoint is both extremely limited and of poor methodologic quality.