If applied incorrectly it may cause further injury, for instance inducing cardiac arrest by blunt trauma, or breaking the tip of the sternum, risking fatal damage to the liver or other abdominal organs.
[citation needed] At one time, the technique was also taught as part of standard CPR training with the requirement that it must be administered within 60 seconds of the onset of symptoms.
That time restriction, combined with a number of injuries caused by improper technique,[citation needed] resulted in the procedure being removed from CPR training.
In 1970, the Charlottesville-Albemarle Rescue Squad (VA) was transporting a patient with an unstable cardiac rhythm in what was then called a Mobile Coronary Care Unit.
When the vehicle inadvertently hit a speed bump in a shopping center parking lot, the patient's normal heart rhythm was restored.