Answer:

Whenever the stroke team calls during a Code Stroke, have a script in mind of what to say. Example: One liner, timing, last known normal, neuro deficits (NIHSS if able), INR/anticogulation, glucose, creatinine, and blood pressure. These are the components that will help the stroke team determine if this patient is a candidate for tPA or thrombectomy.

“Hi Dr. Broderick, I am a huge and of your work. This is a 69 y/o M with a history of Afib on Xarelto admitted for afib w/ RVR now rate controlled. On morning rounds he had new neuro deficits. Last known normal was 3 hours ago at last vitals check. His deficits are a slight left facial droop, no effort against gravity left upper extremity with, complete sensation loss, some left leg drift and ataxia. His INR is 1.3, he has his xarelto this am, his glucose is 172, Cr is 1.1, and his systolic blood pressure is 190mmHg.”

NIHSS:

4 - 1
6a - 1
7 - 1
11 - 1
8 - 2
5a - 3
Total: NIHSS 9

Answer:

We know that anticoagulation decreased risk of stroke based on RCTs that largely exclude ESRD patients, but there are a lot of physiologic differences in ESRD patients. A recent meta-analysis in JACC (Oral Anticoagulation for Patients With Atrial Fibrillation on Long-Term Dialysis) took a look at these patients. They were able to find 16 observational studies that compared various combinations of warfarin or DOAC vs placebo or other AC. They did not see any decrease in stroke risk in this subset of patients, with the caveat that it was a heterogeneous set of patients and studies.

“There were several potential explanations of these findings. First, patients on hemodialysis routinely received heparin during dialysis, which also increased the risk of bleeding and posed a questionable effect of warfarin against stroke prevention. Second, warfarin might accelerate vascular calcification by inhibiting matrix G1a protein and Gas-6, which lead to higher risk of calcific arteriolopathy (calciphylaxis), which might increase the risk of ischemic stroke. Third, uremia was shown to interfere with warfarin metabolism through hepatic P450, which made it difficult to control the international normalized ratio within the therapeutic range. For all of the preceding reasons, we speculated that the previous studies did not show the benefit of warfarin among patients with AF on longterm dialysis; however, frequent international normalized ratio monitoring could lead to a better time to the therapeutic international normalized ratio range and could potentially lead to better outcomes in this cohort.”

We need RCTs to truly answer this question. However, this is a great case in interpreting EBM and paying attention to the patient population studied.

Answer:

What could be going on in this patient? He is obvious septic, likely from a urinary tract infection, and should be treated for that. However, there is a tricky component of the exam - the mild facial droop and confusion. Given that this patient has no known previous normal, changes on his CT Head that are “favored to be chronic”, there is a chance that this is recrudescence. However, this is a difficult diagnosis to make without collateral from the family or previous documented exams with neurological deficits. Additionally, it is really important to differentiate if the patient is truly confused or if they are dysarthric or aphasic and are unable to answer. In patients who are altered and do not follow commands, it is hard to notice strength changes on exam, so it is important not to be reassured that the patient “moves all extremities.”

In the absence of collateral or known previous strokes that would increase suspicion for recrudescence, this patient should get at least get a neurological consultation to help risk stratify. In this setting, it would imperative to get family collateral and discuss with your ED providers regarding the neurologic exam findings. If you are truly concerned, it is not unreasonable to page the stroke team to discuss or call a code stroke.

This patient had an early stroke and progressed to complete hemi-paresis within a few hours. He was altered from his UTI and had not taken his anticoagulation for several days leading to a likely cardioembolic stroke. He was out of the window fro tPA (4.5 hours) but he was still a candidate for thrombectomy based on his CT Perfusion scan.

Below is a brief tutorial on CT Imaging in acute to chronic strokes from radiopaedia which will help you understand why we cannot be reassured by CTs in the acute setting: