First described by an American thoracic surgeon, Henry Heimlich, in 1974, this is a method of relieving choking from a blocked airway, for example when a large item of food has been inhaled instead of chewed and swallowed. It was reported, in 2016, that Dr Heimlich – then in his nineties successfully performed his manoeuvre on a fellow resident of a retirement complex.

The method is as follows:

• Stand behind the person and slightly to one side. Support their chest with one hand. Lean them forward so that the object blocking their airway will come out of their mouth, rather than moving further down.

• Give up to five sharp blows between the person's shoulder blades with the heel of your hand. (The heel is between the palm of your hand and your wrist).

• Check if the blockage has cleared.

• If not, give up to five abdominal thrusts (except in pregnant women or babies under 1 year)

• Stand behind the person who is choking.

• Place your arms around their waist and bend them forward.

• Clench one fist and place it right above their umbilicus. Put the other hand on top of your fist and pull sharply inwards and upwards. Repeat this movement up to five times.

• If the person's airway is still blocked after trying back blows and abdominal thrusts, call for emergency help and continue with the cycles of five back blows and five abdominal thrusts until it arrives.

• The manoeuvre can be performed on a recumbent, unconscious person by kneeling astride them or even on oneself, either with both fists or using the edge of a table or chair to exert the upward pressure.