In medicine and first aid the term ‘shock’ refers to a loss of effective circulating blood volume. This can be from severe bleeding, burns, diarrhoea and vomiting, sweating and dehydration (heat-stroke), severe infection, allergic reactions, or major or multiple fractures, spinal injury, heart disorder including a heart attack, abnormal dilation of blood vessels.

Signs and symptoms

• Dizziness

• Nausea

• Thirst

• Feeling cold

• Muscle weakness

• Shortness of breath

• Anxiety, restlessness

• Rapid pulse, fast heart rate

• Rapid breathing

• Cool sweating pale skin

• Collapse

• Confusion, deterioration of the level of consciousness

• Vomiting

First aid

Call the ambulance, send for resources. For the casualty:

• Rest comfortably, ideally lying down

• Control any bleeding

• Manage airways and unconsciousness

• If they vomit, place on their side

• Keep them warm and still

• Provide reassurance, monitor until the ambulance arrives