In Response to Flush Drowning as a Cause of Whitewater Deaths: Targeting Prevention with Uniform Definitions

To the Editor:

We read with great interest “Flush Drowning as a Cause of Whitewater Deaths.” ¹ We applaud efforts to better define drowning and reduce its burden across diverse environments. The authors use the colloquial descriptor “flush drowning,” although they note it to be an obscure term without consensus definition. They describe it as an alternate cause of death during whitewater activity in which there was no prolonged underwater entrapment. We offer a more concise definition: simply that these patients are drowning.

A working group at the 2002 World Congress on Drowning proposed a uniform definition of drowning: “the process of experiencing respiratory impairment as a result of submersion or immersion in a liquid medium.” ² Explicit in this definition is the exclusion of such modifiers as “wet,” “dry,” “active,” “passive,” “silent,” and “secondary,” which we would expand to include “flush” drowning. This definition was further reinforced in 2003 and has been adopted globally by many organizations, including the World Health Organization, American Heart Association, European Resuscitation Council, Australia New Zealand Committee on Resuscitation, International Liaison Committee on Resuscitation, Wilderness Medical Society, International Lifesaving Federation, American Red Cross, Centers for Disease Control and Prevention, and American College of Emergency Physicians. ^{3 –}5 We suggest that the uniform definition would identify many of these events as “drowning” without additional modifiers.

There are only 3 outcomes of the drowning process: fatal, or nonfatal with or without morbidity. We recognize that identification of environmental circumstances is critical to whitewater safety education and incident prevention. We suggest that it would be more appropriate to describe these events as “fatal drowning caused by” or “nonfatal drowning associated with” and then use the whitewater-specific term as needed.

The authors correctly note that some people die in a whitewater setting while wearing appropriate flotation devices and without fixed, prolonged underwater submersion. The uniform definition of drowning describes respiratory impairment to be caused by immersion, which can be caused by intermittent airway obstruction and aspiration while wearing a personal flotation device in whitewater (eg, after an unplanned swim in rapids or recirculation in hydraulics).

More pointedly, there may be a subset of these drowning patients for whom airway compromise was secondary to loss of consciousness due to some other etiology. Emerging research into autonomic conflict, cold water shock, cardiac arrest, and other medical etiologies that precipitate drowning in otherwise healthy persons may provide future insight.

The authors address 2 important aspects of the drowning chain of survival in the whitewater setting: prevention and treatment.^1,4,6 Uniform terminology can improve classification of the events leading up to drowning. Identifying whether the cause of drowning is entrapment in a strainer, short flush entrapment, entrapment in boats or sieves, or loss of consciousness due to head trauma can identify opportunities for prevention, education, treatment, and the development of safety equipment. Classifying these incidents according to the uniform definition of drowning may allow for further multi-sectorial research, particularly in the ocean rescue, search and rescue, offshore, and aquatics industries.