How can we identify if a person is suffering a stroke?

Stroke symptoms

Ask the person to raise both arms at the same time to check if anything unusual occurs. If the person is unable to lift one arm or the other due to weakness, this may be a sign of a stroke. If they feel weakness in the legs, ask them to sit down and lift both feet at the same time.

Ask them to smile to detect whether one corner of the mouth droops to one side (a crooked smile). Facial paralysis is related to stroke and may be accompanied by a tingling or numb sensation. Sometimes, vision loss may also occur.

Ask simple, specific questions such as what an object you are pointing at is, or what is happening around them. The aim is to observe whether they mix up syllables or mispronounce the name of the object (in the first case), and whether they respond in a fragmented way or speak incoherently (in the second). This helps check for difficulties in speech and understanding.

First aid

Every minute, 1.9 million neurons and 14 trillion neural connections are lost: one hour can mean the equivalent of 3.6 years of brain ageing and a loss of 120 million neurons.

If you suspect that a person may be suffering a stroke, call emergency services immediately (112 in Spain). While waiting for medical help to arrive:

Keep the patient calm and still.  
Ideally, lay them down to improve cerebral perfusion.  
If they are unconscious but breathing, place them in the recovery position.  
Keep the head flat (unless they are vomiting or having difficulty breathing).  
Do not administer any medication that has not been prescribed by a healthcare professional.  
Call emergency services to confirm the most appropriate hospital and allow pre-notification to the receiving centre.  
Avoid intermediate care levels (such as primary care centres or general practitioners), as they may delay the start of acute treatment.