Is CPR performed any differently for victims of drowning?
With summer on the way (or in Seattle, already here, based on the weather), people are spending more time in or near the water. Whether it be the ocean, a lake or river, or swimming pool, more folks are hopping in. While this is a great recreational opportunity, it also presents additional dangers.
King County last compiled preventable drowning death statistics for the years 2008-2012 (link to pdf here). These statistics covered 92 cases. Statistics indicated that drownings peaked in the period from July to September, the victims were most often male Caucasians between 25 and 44 years old, and in 46% of the cases, alcohol and/or drugs were involved. The highest number of incidents occurred in open water, with private pools/tub being the second most common.
“Is CPR performed any differently for victims of drowning?” is a question our instructors often field during CPR classes at CPR Seattle. The most important thing to remember is that for anyone who is unresponsive and isn’t breathing, CPR needs to be started immediately. Following the specific priorities learned during your CPR training is the easiest way to get CPR started for the drowning (or more accurately, near-drowning) victim. Make sure to always call 911 first before trying to rescue a victim and/or begin CPR. Rescuers must also keep themselves safe during any rescue attempt.
Near-drowning happens when a person is unable to breathe due to extended submersion in water. Just as in other respiratory-based issues, the body’s systems will shut down due to the lack of oxygen, and can easily result in the rapid onset of brain damage (this usually occurs faster in children than in adults). Even if a near-drowning victim has been submerged for a long period, CPR may still be effective – especially in cases where the water is cold.
One concern expressed by CPR Seattle students is what to do about the water that has entered the lungs, and how much the aspirated water will interfere with rescue breaths. When water enters the airway both conscious and unconscious victims will experience laryngospasm (the involuntary constriction of the larynx), which will seal off the airway. This means that water will enter into the stomach rather than the lungs. Around 7-10% of victims maintain this seal up to the point of cardiac arrest. Therefore there is usually no need to clear the airway of water, as only a small amount is aspirated, and that which is aspirated will normally be absorbed into the bloodstream.
Cardiac arrest in near-drowning victims is caused by lack of oxygen and physical changes to the blood.
In salt water, osmosis pulls water out of the bloodstream and into the lungs, making the blood thicker and taxing the heart. In fresh water, osmosis works in the opposite direction, diluting the blood, destroying red blood cells, and altering electrical activity in the heart. These can all result in cardiac arrest.
The current CPR guidelines indicate that CPR should begin with chest compressions. Due to the conditions associated with near-drowning, the AHA advises rescuers to deliver two rescue breaths first, and then begin the cycles of compressions and breaths as directed. This especially applies to BLS-trained EMS professionals, but is advised for all rescuers. Breaths may be given mouth-to-nose if the rescuer and victim are both still in the water, as mouth-to-mouth ventilations may be difficult to perform.
Victims of near-drowning who receive chest compressions might vomit. A ten-year Australian study showed that for the victims who received compressions, 86% vomited. Rescuers should turn the victim on his/her side and clear the airway with fingers or cloth.
As stated, rescuers of near-drowning victims should always ensure their own safety before attempting any rescue, especially an in-water rescue. Even strong swimmers can find it difficult to swim with an unconscious person.
2010 American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science Part 12: Cardiac Arrest in Special Situations http://circ.ahajournals.org/content/122/18_suppl_3/S829.full#sec-109
Seattle Children’s Hospital: Drowning Prevention Reports & Data http://www.seattlechildrens.org/classes-community/community-programs/drowning-prevention/data/
Drowning and near-drowning on Australian beaches patrolled by life-savers: a 10-year study, 1973-1983. http://europepmc.org/abstract/med/3340043
Published on June 9, 2015