An Acute Stroke
An Acute Stroke
08.23.2023
Quick scene time and early recognition result in optimal outcomes
Dr. Jordan Singer
Case Summary:
An ALS crew was dispatched to a middle-aged man for a possible stroke. The found him outside on the grass. He reported that he had just finished cutting the grass and noticed that his left side suddenly became numb, and he could no longer hold himself up causing him to fall to the ground but not hit his head. This occurred 15 minutes before the crew arrived on scene. The crew quickly performed a Cincinnati stroke scale to screen for stroke which came back positive. They then quickly checked a glucose which came back at 102. They then extricated the patient to the rig and deferred all other evaluation and care until wheels were rolling towards the ED. The time between patient contact and wheels rolling was 5 minutes.
While in route, they notified the receiving hospital of a potential stroke patient to ensure they were ready to receive the patient. The also obtained a complete set of vitals, placed and IV and obtained a 12-lead EKG.
Vitals: BP 135/73, HR 101, RR 20, Sat 96% RA, ETCO2 22
The crew performed a more thorough neuro exam while in route and found that he had slurred speech but not aphasia, left sided weakness and sensory loss to the upper and lower extremities. The found him to be VAN negative and he reported he was not on any blood thinners. They also noticed that his weakness would was and wan but never fully resolve. The crew arrived at the receiving hospital and handed of care 15 minutes after patient contact.
Highlights of the case:
For acute strokes, the priority is transport.
Most medical patients are stay and play since immediate care and resuscitation on scene is more important than transport to the hospital. Acute stroke patients are an important exception to this rule. Once we perform our Cincinnati stroke scale and it is positive for concern for stroke AND the last known well is <24 hours, our goal is extrication. We want the time between patient contact and wheels rolling to the ED to be as soon as possible. The only things that should take priority to over transport is checking/treating the glucose if low and ensuring a radial pulse (implying good perfusion). Everything else: IV, EKG, VAN (or other stroke severity score), full set of vitals, ect, should happen while transporting. If you do not have time to do these things, that is fine as long as it was because you prioritized transport. The reason is that patients with acute strokes lose 100,000 neurons every minute they have not been treated. Most patients would prefer a couple 100,000 neurons to a prehospital IV, a full set of vitals or an EKG. The crew in this case performed textbook acute stroke care by prioritizing transport over almost everything to minimize the neuronal damage from the stroke. The only things the did prior to extrication was perform the Cincinnati stroke scale, check the patients glucose and ensure a radial pulse was present.
Determine an accurate last known well whenever possible.
For acute strokes, we only have two current ways of treating the stroke and both of these treatments can only be used within a certain timeframe from the patients last known well (LKW). One of the treatments is to give a medication that breaks down the clot, which is known as thrombolysis. This can only be done within 4.5 hours of last known well if the patient meets certain criteria. The other treatment is for a wire to be fed through his/her arteries into the brain and to have the clot removed, which is known as mechanical thrombectomy. This can be done for very specific, but severe, strokes within 24 hours of last known well. It is important to note that families/patients often mention the time that they first see something wrong as the LKW since that is the trigger for calling EMS, however, that is the "first known abnormal" time. “First known abnormal” time is a term I made up and is not useful in stroke care. We need to confirm and document that the family saw the patient at their neuro baseline at X time and that they were found in their new neuro state at Y time. This makes it clear. If a patient is witnessed to go from normal to abnormal at a specific time, then X and Y might be the exact same time. If the LKW time is <24 hours, the priority is rapid transport since this patient is having an acute stroke. If the last known well is >24 hours prior, there is no rush to get the patient to the hospital since the stroke is too old for us to treat the patient with any of the time sensitive treatments. It is still very important for the patient to be transported since the patient will need care to prevent another stroke as well as rehab services to help gain functionality back. This crew determined an accurate LKW since they explained that the patient remembered the exact moment he went from his neuro baseline to developing his symptoms.
Perform a stroke severity exam while in route.
Once we determine that a patient is having an acute stroke and initiate prompt transport to a stroke center, we should attempt to perform a stroke severity score to see if there is evidence of a large vessel occlusion (LVO). LVOs are severe strokes that may be a candidate for mechanical thrombectomy. The reason this is important is that only very specialized centers have the capability to perform this procedure. The two types of facilities that can do this are thrombectomy capable centers and comprehensive stroke centers. If you are heading towards a primary stroke center and your stroke severity exam points towards an LVO, it would be reasonable to divert to a thrombectomy capable or comprehensive stroke center if it is <15m further than the primary stroke center. This would mean a delay to thrombolysis but much quicker access to thrombectomy. Given that thrombectomy has been shown to be so successful in stroke management, this trade-off is well worth it. The stroke severity scale we use in our system is the VAN score. This crew performed a VAN score in route and found it to be negative meaning the patient in this case was unlikely to be having an LVO and that they should continue toward their initial destination which was a primary stroke center. While performing a stroke severity score is important, it should be done while in route and should not delay transport.