Cardiopulmonary resuscitation (CPR) is one of the foundations of emergency medical care. It is a required training for nearly all emergency medical providers in the U.S. and is widely taught to the public as part of secondary education.
As of 2017, in fact, all but 12 U.S. states (Alaska, California, Colorado, Florida, Hawaii, Kansas, Nebraska, New Hampshire, Maine, Massachusetts, Montana, and Wyoming) require that students be taught CPR before graduating high school.
When performed correctly, CPR can double or triple a person's chance of survival, according to statistics from the American Heart Association (AHA). However, in recent years, one facet of CPR, known as rescue breathing (or mouth-to-mouth resuscitation), has come under fire by those who believe that it can sometimes do more harm than good.
Since its introduction in the 1960s, CPR has gone through a number of incarnations. Today, most people associate it with two practices – mouth-to-mouth breathing and chest compression – which are sometimes performed in tandem on persons with cardiac arrest.
Of the two practices, mouth-to-mouth resuscitation was introduced first. It was the standard method for reviving victims of drowning well before the advent of CPR and has remained an integral part of the practice ever since.
However, the combination of the two has not been without its challenges both in how they are performed and how effective they are in improving survival.
Complications in Traditional CPR Training
One of the major barriers to teaching CPR is getting the ratio of rescue breathes to chest compression right. This is especially true if one person is performing both tasks. It requires a person to not only perform but remember each step of the process in the correct order to achieve the best results.
Prior to the introduction of newer guidelines, the following steps would be asked of the rescuer:
Determine if the victim is breathing.
Check for a pulse to see if the heart is beating.
Clear the victim's mouth of any obstruction.
Give the victim 15 chest compressions.
Pinch the victim's nostrils and give two rescue breaths.
Continuing giving 15 chest compressions followed by two rescue breaths until emergency help arrives.
All of these steps combined made CPR difficult to remember in high-stress situations. Even with two rescuers, remembering how the take a pulse, where to compress the chest, or how to give mouth-to-mouth could be challenging and increase the overall risk of error.
Research Lead to Changes in Guidelines
In light of growing evidence in support of chest compression, the AHA Committee on Emergency Cardiac Care made significant changes to the CPR guidelines in 2005. Among them, the committee recommended that more compressions be made between rescue breaths and advised that lay rescuers no longer check for a pulse before starting CPR.
The changes were initially met with harsh criticism by many in the emergency medical services (EMS) who considered mouth-to-mouth central to the CPR practice. Even electrical defibrillators were given a lesser role in the guidelines as chest compression took center stage as the technique most likely to save lives.
Despite the initial outcry, the AHA recommendations were supported by numerous studies which demonstrated that chest compression performed alone increased a person's chance of survival compared to combining compression and rescue breathing.
In 2010, a randomized study called the Dispatcher-Assisted Resuscitation Trial (DART) compared the two practices at EMS sites in Washington state and London. What the researchers found was that, in cases where a bystander performed CPR, victims given chest compressions alone had a 39 percent greater chance of survival compared to those given both compression and mouth-to-mouth.
This and other studies have largely concluded that the benefits of mouth-to-mouth in bystander emergencies remain questionable at best.
While the evidence doesn't entirely erase the value of traditional CPR (or halted its teaching in public schools), a modified form of CPR has since been introduced to simplify the process.
Dubbed as hands-only CPR, the revised practice is designed to give greater confidence to persons who need to perform life-saving efforts in persons with cardiac arrest. The simplified procedure involves just two steps:
Call 911 if a teen or adult suddenly collapses.
Push hard and fast in the center of the chest to the beat of a song that has 100 to 120 beats per minute, such as "Staying Alive" by the Bee Gees, “Crazy in Love” by Beyoncé, or "Walk the Line" by Johnny Cash.
By keeping the practice simple, the likelihood of error is decreased without reducing a person's chance of survival.