Drowning Facts

Drowning is the process of experiencing respiratory impairment from submersion/immersion in liquid. Drowning outcomes consist of death, morbidity, and no morbidity. This definition, along with other issues of terminology related to submersion incidents were determined by the experts who made up the 2002 World Conference on Drowning.

Drowning Terms -  Old and New

drowning3The delegates at the 2002 World Conference on Drowning agreed on new terminology for drowning so that generalized, imprecise terms (like some of the ones that follow) can be eliminated. Unfortunately, to drop outdated terms, we have to list them below so you know which they are (now, that’s irony!) In addition, discussion forums, lifesaving and water safety resources, and the media still use these terms, so it makes sense to know both the classic terms and the new equivalents.

  • Prior to 2002, drowning meant death by suffocation in water or other liquid within 24 hours. Near drowning described a submersion incident that did not lead to death during the first 24-hour period following recovery/rescue. Following the 2002 World Conference on Drowning, the new definition for drowning encompassed a broader range of outcomes: drowning with no morbidity, drowning with morbidity, and drowning-related death or fatal drowning. These are the preferred terms in use today.
  • Dry drowning refers to a drowning victim with an laryngospasm that remains in place until the victim stops breathing so very little water enters the lungs. The opposite of dry drowning is wet drowning, where the laryngospasm relaxes as the victim becomes hypoxic so water can enter the lungs as the victim takes his or her last breaths (fluids do not passively enter the lungs).
  • Secondary drowning refers to a drowning complication caused by breathing fluids into the lungs. This can cause acute secondary lung injury, noncardiogenic pulmonary edema, or acute respiratory distress syndrome (ARDS). A person with this complication can seem completely recovered from a drowning only to experience severe symptoms hours later, including coma and death. The term secondary drowning (also known as delayed drowning and, erroneously, as dry drowning) focuses on the suspected first cause for the complication and implies that this is a type of drowning, albeit delayed, dry, or secondary. Under the new definition of drowning, this complication is an outcome of drowning. ABCNews and Livestrong have published articles about this complication.
  • Active and passive drowning refer to victim states during the drowning process. Although these terms will probably continue to be used in the context of victim recognition, both are drowning victims who at the moment of rescue are in different drowning states.

Other terms related to drowning include:

  • Distressed swimmer is a term used in Red Cross Lifeguarding for someone (presumed to be a swimmer) who can support himself/herself at the surface but, due to illness, injury, or exhaustion, cannot make progress through the water to safety. The Red Cross definition is actually much too narrow. Nonswimmers can also be distressed victims; many have been rescued while holding onto an overturned boat in open water, a lane line or float in a swimming pool, etc.
  • Immersion syndrome is sudden death due to the shock of cold water, which can trigger hyperventilation, tachycardia, and sudden cardiac arrest.
  • The mammalian diving reflex is a phenomenon that enables some people to be revived after prolonged submersion in icy cold water. Click the link to learn more about the mammalian diving reflex. Click this link to see a brief experiment regarding the mammalian diving reflex.
  • Submersion injury is a first aid term that can be used to describe the detrimental effects of drowning on the patient (in other words, drowning with morbidity).
  • A victim is someone drowning or in distress who needs to be assisted or rescued

Drowning Facts/Stats

The Centers for Disease Control, the U.S. Consumer Product Safety Commission (CPSC), and the World Health Organization list drowning facts and statistics. The United States Lifesaving Association publishes rescue and drowning statistics for U.S. beaches. A study published in 2011 by the American Academy of Pediatrics identified activities and scenarios that precede the drowning of very young children.

Drowning statistics by state, county, country, or region::

Other sites for drowning facts include:

The Drowning Process

drowning1When a nonswimmer is immersed in water without support, he or she begins exhibiting the instinctive drowning response. The instinctive drowning response, a term coined by Frank Pia, Ph.D, is what a victim does in the water to avoid suffocation. The victim is vertical in the water with head held back and mouth open, arms are extended and may press down, and there is no supporting kick. The victim usually cannot wave or call out for help because he or she is unsupported and instinctively focusing all efforts on staying at the surface. The victim may sustain this for up to about 60 seconds before becoming exhausted and submerging.

When water covers the victim’s mouth and nose, breathing is compromised. The victim holds his or her breath for as long as possible, eventually gasping for air and instead swallowing water. Water rushes into the airway, irritating the back of the throat and causing laryngeal spasm, which blocks the airway and leads to hypercarbia, hypoxia, and acidosis. They may swallow large amounts of water.

In many cases, the laryngeal muscles relax, and the victim aspirates fluids into lungs, resulting in further hypoxia due to the destruction of sulfactant and massive pulmonary shunting. Without prompt rescue and resuscitation, the victim will soon suffer death due to hypoxia or secondary cardiac arrhythmias from diffuse acidosis. Following cardiac arrest (sometimes referred to as clinical death, based on Black’s Law Dictionary definition of death), irreversible brain damage due to hypoxia begins within as little as 4 to 6 minutes (sometimes called biological death). Even if the victim is revived before brain damage begins, the victim can suffer from secondary lung injury, renal failure, or disseminated intravascular coagulation. Other complications from drowning include ARDS and pneumonia.

NOTE: In 1968, an ad hoc committee of the Harvard Medical School redefined biological or brain death as an irreversible coma to make the harvesting of organs a more practical and less confusing and controversial practice. The common definitions of clinical and biological death may still be the most appropriate outside the hospital for lifesavers/lifeguards/EMS personnel to encourage CPR, oxygen administration, AED application, and advanced life support when faced with a seemingly lifeless patient.

In 2008, Emergency Physicians Monthly published an excellent article on drowning, called Drowning: A Brief Primer on Submerged Injuries. Other articles on the science of drowning follow: