Abdominal thrusts

Abdominal thrusts, also known as the Heimlich maneuver or Heimlich manoeuvre, is a first-aid procedure used to treat upper-airway obstructions (or choking) by foreign objects. American doctor Henry Heimlich is often credited for its discovery. To perform abdominal thrusts, a rescuer stands behind a choking victim and using the hands to exert pressure on the bottom of the diaphragm. This compresses the lungs and exerts pressure on the object lodged in the trachea in an effort to expel it.

Most modern protocols, including those of the American Heart Association, American Red Cross and the European Resuscitation Council, recommend several stages for airway obstructions, designed to apply an increasing level of pressure. Most protocols recommend encouraging the victim to cough, followed by hard back slaps, and finally abdominal thrusts or chest thrusts as a final resort. Some guidelines also recommend alternating between abdominal thrusts and back slaps.

History
Thoracic surgeon and medical researcher Henry Heimlich, noted for promulgating abdominal thrusts, claimed that back slaps were proven to cause death by lodging foreign objects into the windpipe. A 1982 Yale study by Day, DuBois, and Crelin that persuaded the American Heart Association to stop recommending back blows for dealing with choking was partially funded by Heimlich's own foundation. According to Dr. Roger White of the Mayo Clinic and American Heart Association (AHA), "There was never any science here. Heimlich overpowered science all along the way with his slick tactics and intimidation, and everyone, including us at the AHA, caved in."

From 1985 to 2005, abdominal thrusts were the only recommended treatment for choking in the published guidelines of the American Heart Association and the American Red Cross. In 2006, both organizations drastically changed course and "downgraded" the use of the technique. For conscious victims, the new guidelines recommended first applying back slaps. If this method fails to remove the airway obstruction, rescuers are to then apply abdominal thrusts. For unconscious victims, the new guidelines recommended chest thrusts.

Henry Heimlich also promoted abdominal thrusts as a treatment for drowning and asthma attacks. The Red Cross now contests those claims. The Heimlich Institute has stopped advocating on their website for the Heimlich maneuver to be used as a first aid measure for drowning victims. Heimlich's son, Peter M. Heimlich, alleges that in August 1974 his father published the first of a series of fraudulent case reports in order to promote the use of abdominal thrusts for near-drowning rescue. The 2005 drowning rescue guidelines of the American Heart Association did not include citations of Heimlich's work, and warned against the use of the Heimlich maneuver for drowning rescue as unproven and dangerous, due to its risk of vomiting leading to aspiration.

In May 2016, Henry Heimlich, then age 96, claimed to have personally used the maneuver to save the life of a fellow resident at his retirement home in Cincinnati. It was alleged to be either the first or second time Heimlich himself used his namesake maneuver to save the life of someone in a non-simulated choking situation. According to Heimlich's son, Peter M. Heimlich, "both 'rescues' were bogus."

Universal sign of choking
A choking victim is usually unable to speak, and may not be able to make much sound. A universal sign of choking has been designated as a silent indication from a person who is unable to breathe, and consists of placing both hands on one's own throat while trying to attract the attention of others who might help.

Technique
Both the American Red Cross and UK National Health Service (NHS) advise that for a first attempt, a rescuer should encourage the patient to expel the obstruction by coughing. As a second measure, the rescuer should deliver five slaps to the back after bending the patient forward. Abdominal thrusts are recommended only if these methods fail.

The American Red Cross, the NHS, the European Resuscitation Council and the Mayo Clinic recommend a repeating cycle of five back slaps and five abdominal thrusts. They are not recommended on children below the age of one. In contrast to the prevailing American and European advice, the Australian Resuscitation Council recommends chest thrusts instead of abdominal thrusts.

To perform abdominal thrusts, a rescuer stands behind an upright patient, using the hands to exert forceful pressure on the bottom of the diaphragm. As an example, WebMD recommends making a fist with one hand and grasping the fist with the other in order press with both just above the patient's navel. This compresses the lungs and exerts pressure on any object lodged in the trachea in an effort to expel it. The pressure amounts to an artificially induced cough. To assist a larger person, more force may be needed. The Mayo Clinic recommends the same placement of fist and hand, with upward thrusts as if the rescuer is attempting to lift the victim.

If the victim cannot receive pressure on the abdomen (for example, in case of pregnancy or excessive obesity), chest thrusts are advised. These are applied on the lower half of the chest bone, but not in the very endpoint (the xiphoid process, which could be broken).

For victims who are not in an upright position, The American National Institutes of Health recommends positioning the victim on the back, then straddling the torso and employing chest thrusts.

It is possible for conscious choking victims to perform the procedure on themselves, without assistance.

Because of the forceful nature of the procedure, even when performed correctly, abdominal thrusts can injure the victim. Bruising to the abdomen is highly likely and more serious injuries can occur, including fracture of the xiphoid process or ribs. The NHS recommends that victims subjected to abdominal thrusts should seek medical attention after the event.

Researchers at Royal Brompton Hospital have demonstrated that levels of intrathoracic pressures (50–60 cmH2O) exerted by inward abdominal thrusts are similar to those produced when the force is directed both inward and upward. The researchers argue that this may be easier to perform with less concern for injury to the rib cage or upper abdominal organs. Self-administered abdominal thrusts by study participants produced similar pressures to those generated by administers of first aid. The highest pressures were produced by participants performing an abdominal thrust by pressing onto the back of a chair (115 cmH2O).