For World Stroke Day 2018, we bring to you a comprehensive set of the latest 2018 recommendations/updated guidelines by the American Heart Association (AHA) / American Stroke Association (ASA) provided for clinicians managing adult patients with acute arterial ischaemic stroke.

These updated 2018 guidelines take into account findings from six positive “early window” mechanical thrombectomy trials (MR CLEAN, ESCAPE, EXTEND-IA, REVASCAT, SWIFT PRIME, and THRACE) that were done in 2015 and 2016, and two very recent 2018 trials (DAWN and DEFUSE 3) that showed a clear benefit of “extended window” mechanical thrombectomy for certain patients with large vessel occlusion who could be treated out to 16-24 hours. Here are the key points that should be remembered:

1. Intravenous (IV) tissue plasminogen activator (tPA) has time-dependent benefits and therefore, treatment should be started as early as possible in the eligible patients as well as in patients for mechanical thrombectomy.
2. All eligible acute stroke patients should be administered IV tPA within 3 hours of last known normal, and within 4.5 hours of last known normal to a more selective group based on ECASS III exclusion criteria. In ≥50% of stroke patients treated with IV tPA, centers should make an effort to attain door-to-needle (DTN) time of less than 60 minutes.
3. A DTN times of 45 minutes or less in 50% of patients with acute ischaemic stroke as a secondary goal is most significant as it helps to maximise the critical timeline in stroke triage and initiation of treatment with tPA.
4. A non contrast head computed tomography (CT) and glucose are the only tests required before the start of IV tPA in the majority of patients. If underlying coagulopathy is not suspected, there is no need to get results of the international normalised ratio, partial thromboplastin time, and platelet count before the initiation of tPA.
5. In ≥50% of stroke patients, centers should strive for a non contrast head CT within 20 minutes of patient arrival as the patient may require IV tPA or mechanical thrombectomy. In ≥50% of patients for whom IV alteplase and/or thrombectomy may be indicated, centres should have systems in place that make it possible to perform brain imaging studies within 20 minutes of arrival to the ED.
6. An urgent CT angiogram or magnetic resonance (MR) angiogram which can be used for detect large vessel occlusion is recommended for patients requiring mechanical thrombectomy but if IV tPA is indicated, this investigation should not delay treatment.
7. Mechanical thrombectomy with a stent retriever should be done in the patients of greater than 18 years of age and if they possess minimum pre stroke disability, a causative occlusion of the internal carotid artery or proximal middle cerebral artery, a National Institutes of Health stroke scale score of ≥6, supportive non-contrast head CT (ASPECT score of ≥6) and if they can be treated within 6 hours of last known normal. These patients do not require perfusion imaging (CT-P or MR-P). Providers should not use the CT hyperdense middle cerebral artery sign as a criterion to withhold tPA from patients who would be candidates otherwise.
8. To determine whether the patient can undergo mechanical thrombectomy or not, perfusion imaging (CT-P or MR-P) or an MRI with diffusion-weighted imaging (DWI) sequence is recommended in selected acute stroke patients within 6-24 hours of last known normal who have confirmed large vessel occlusion in the anterior circulation and are eligible for DAWN or DEFUSE 3.
9. Mechanical thrombectomy is recommended in select acute stroke patients within 6-16 hours last known normal that have a large vessel occlusion in the anterior circulation and fulfill the DAWN or DEFUSE criteria. The use of a stent retriever for mechanical thrombectomy is reasonable in the select acute stroke patients within 6-24 hours of last known normal that have large vessel occlusion in the anterior circulation and fulfill the DAWN eligibility criteria.
10. Mechanical thrombectomy treatment should be started as early as possible as is done with IV tPA. In acute stroke patients, aspirin is recommended within 24-48 hours after the onset of stroke. A 24-hour delay in aspirin administration is recommended in IV tPA treated patients. In most stroke patients, urgent anti-coagulation via a heparin drip is contraindicated.
11. For all patients with acute stroke, the use of stroke units that include rehabilitation is recommended.
12. There is no surety of whether there is any benefit for emergency medical services to bypass a nearby IV tPA-capable hospital if favor of a thrombectomy-capable hospital. Doing so, may delay IV tPA administration in patients who may or may not be mechanical thrombectomy candidates, but this would hasten thrombectomy in potential mechanical thrombectomy patients.
13. Triage paradigms and protocols should be created after coordination between emergency medical services (EMS) leaders and local, regional, and state agency medical experts to assist in the rapid detection and evaluation of patients with stroke or suspected stroke. Validated stroke screening tools such as the Face Arm Speech Test (FAST), the Cincinnati Prehospital Stroke Scale, or the Los Angeles Prehospital Stroke Screen should be used.
14. The telemedicine section revision included the use of teleradiology and telestroke services for the faster assessment of neuroimaging at sites without such in-house capabilities, and for tPA administration and the decision to transfer patients for thrombectomy, telestroke support and guidance were suggested.
15. Developing a stroke data repository to promote compliance to present guidelines, better patient outcomes, and facilitate quality development was recommended to hospitals.

These guidelines, therefore, replace the guidelines given in 2013 and any updates given thereafter and can be used by pre-hospital care providers, physicians, allied health professionals, and hospital administrators.