Strokes occur when part of the brain’s blood supply is cut off. This can be caused by a local haemorrhage or a blood clot in one of the arteries supplying the brain. For more information, see Strokes.

Stroke symptoms include inability to speak, severe headache, confusion, and a pounding pulse. There may be weakness and numbness on one side of the body and unequal dilation of the pupils. In a major stroke, the casual quickly becomes unconscious.

Check breathing and heartbeat and if necessary give artificial respiration (see Breathing) and cardiac resuscitation (see Circulation). If the person is unconscious, place him or her in the recovery position (see Unconsciousness). If the person remains conscious, prop him or her up in a half-sitting position and give as much comfort and reassurance as you can. Dial 911.