Choking: The Heimlich Abdominal Thrust vs. Back Blows: An Approach to Measurement of Forces.

Day RL, Crelin ES, DuBois AB Pediatrics 1982 Vol. 70 Pages 113-119

The authors used a number of techniques to compare pressures generated by the Heimlich maneuver to those found with back blows in four adult subjects. In contrast to previous results by Gordon et al, their data shows the Heimlich maneuver as a powerful one, producing at least twice as much pressure as previously believed. In one example, two back blows raised air pressure in the lungs by 7 and 13 mmHg respectively, while a single Heimlich maneuver raised pressure by 27 mmHg. The authors found that back blows produce less pressure than the Heimlich maneuvers in seated subjects. In addition, back blows throw the head and neck forward and upward due to straightening the spine. Such blows theoretically can displace supraglottic foreign bodies further downward and backward into the throat or larynx. The authors conclude that while their results cannot be considered final, they point to the effectiveness of the Heimlich maneuver under the experimental conditions described, and the potential of back blows to do harm.