This question comes from one of our telephone triage nurses at Pediatric Alliance — Northland:

I have been receiving multiple calls from parents who are concerned with “dry drowning”. I spoke with one of our physicians here about the topic and I think parents are confusing “dry drowning” —  which seems to be a media term — for the significant events of “near drowning” and “drowning”. I was wondering if you could clear up the differences between a little gulp of water and a significant event. For example: I received a phone call from a mom who has a toddler who dumped a glass of water on themselves and has a croupy cough but no signs or symptoms of distress.

 

The medical terminology used to differentiate between different types of drowning (wet, dry, near, passive, secondary, silent, etc.) has been controversial for years. In 2005, after much debate by researchers and clinicians, the World Health Organization adopted the following definition:

“Drowning is the process of experiencing respiratory impairment from submersion/immersion in liquid.”

 

There are three possible outcomes that result from drowning: death; survival with complications (previously referred to as near drowning) causing physical impairment such as adult respiratory distress syndrome and/or mental impairment from hypoxic brain damage; and survival without complications (no impairment). Here are some not-so-fun-facts regarding drowning:

> Drowning is the third leading cause of accidental death worldwide.

> According to WHO, more than 350,000 people die every year from drowning, although this number may be grossly underestimated.

> China and India account for nearly half of all drownings worldwide.

> 90% of drownings occur in freshwater (rivers, lakes, swimming pools) and 10% take place in seawater.

> Populations at highest risk of drowning include children under the age of 5 years old; teenagers and young adults between 15-24 years old; males (80% of victims); adults who don’t know how to swim, including members of minority groups who lack access to learning basic swimming skills.

> Infants most commonly drown in bathtubs, children under 5 in residential swimming pools, and teenagers/young adults in larger bodies of water.

> Use of alcohol greatly increases the risk of drowning.

> Learning how to swim greatly reduces the risk of drowning.

> Ineffective adult supervision is commonly associated with drowning episodes in children.

> Failure to wear life jackets or have access to personal floatation devices was linked to 88% of boating accident drownings in the U.S. in 2010.

 

Emergency medicine physician Dr. Benjamin Wedro explains the mechanism of injury resulting from drowning in an interesting review article:

Drowning occurs when water comes into contact with the larynx (voice box).

  • After an initial gasp, there is a period of voluntary breath holding.
  • This is followed by spasm of the larynx and the development of hypoxemia… or decreased levels of oxygen in the bloodstream.
  • Lack of oxygen causes aerobicmetabolism to stop, and the body becomes acidotic. If not corrected quickly, the lack of oxygen in combination with too much acid may lead to problems with the electrical conduction system of the heart (cardiac arrest) and lack of blood supply to the brain.
  • As body function declines, aspiration may occur as the larynx relaxes allowing water to enter the lungs. However, up to 20% of drowning victims have persistent spasm of the larynx, and no water is aspirated (this was formerly known as “dry” drowning).

 

People who initially survive an acute drowning event can develop complications and become very sick over a period of 24-72 hours after being pulled from water, depending on the duration and extent of the hypoxia and the amount and effect of water aspirated into the lungs. In the example given at the top of this post, the toddler appears to have aspirated (choked) on a small amount of water, causing him to have a spasm of his vocal cords (laryngospasm), which resulted in a croupy-sounding cough. (You can read a personal story about laryngospasm here.) Since the volume of water was small and no respiratory impairment (hypoxia) developed as a result of the croupy cough, the toddler did not experience a drowning event — wet, dry, near, or otherwise.

 

(Google Images)