What is Dry Drowning?
In 2008, a ten-year-old boy in South Carolina died in his bed an hour after swimming in a pool for the first time. His death was attributed to a phenomenon known as dry drowning. Dry drowning is believed to be responsible for an estimated 10%-15% of all reported drownings, although it can be notoriously difficult to diagnose during the essential first hour after onset of symptoms.
Contrary to popular belief, drowning does not necessarily involve a wholesale ingestion or aspiration of water or other fluids. During cases of dry drowning, very little fluid is actually present in the victim's lungs. The problem is that the lungs are no longer able to deliver life-sustaining oxygen to the bloodstream, and the victim eventually succumbs to the lack of oxygenated blood. Death is generally attributed to a pulmonary edema, similar to the effects of acute pneumonia or wet drowning.
One thing which makes dry drowning so difficult to detect is the slow acting nature of the condition. A victim may breathe in a very small amount of fluid and believe he or she has successfully expelled it through coughing. In reality, the water may fill up some of the oxygen-rich pores of the lungs, reducing the lungs' ability to oxygenate the blood as it passes through. The heart does not slow down appreciably during this process, so the victim can still walk and talk. The only symptoms may be a sudden change in personality or level of awareness as the blood oxygen level drops over time.
Another complication which makes treatment of dry drowning difficult is a reflex action known as a laryngospasm. Some people experience an involuntary closing of the larynx when water or other fluids are breathed in. Ordinarily, this laryngospasm should only last 30 to 60 seconds, but in the case of dry drowning, it can continue for several minutes. Meanwhile, the diaphragm drops, creating a partial vacuum in the lungs. Instead of drawing in a breath of outside air, however, this action pulls more oxygen-starved blood into the lungs.
Eventually this overabundance of blood and the inability to draw in or expel air causes the victim to literally drown in his or her fluids. Even if a victim can force some air past the closed larynx, it would not improve the situation. Ordinary CPR or a standard oxygen mask would also have little effect on a dry drowning situation. The only treatment possible would be to create a high-pressure environment in which the vacuum in the lungs is eased and normal respiration can be restored safely.
Because victims may or may not feel the effects of dry drowning immediately, others may need to be more observant after a child leaves a swimming area. Vomiting or involuntary defecation immediately following a swimming session should be considered a red flag. A sudden change in personality or energy level, such as agitation or extreme lethargy, may be a sign of oxygen deprivation. If a child has aspirated water while swimming, he or she should be observed for several hours for signs of labored breathing or altered mental status. Successful treatment for dry drowning victims depends heavily on a swift response and a quick diagnosis by trained medical personnel.
Written by Michael Pollick
