Instinctive Drowning Response
Dr. Francesco A. Pia coined the Instinctive Drowning Response, which ” represents a person’s attempts to avoid the actual or perceived suffocation in the water. The suffocation in water triggers a constellation of autonomic nervous system responses that result in external, unlearned, instinctive drowning movements that are easily recognizable by trained rescue crews.
This is not to say that a person in the water that is shouting and waving is fine and doesn’t need assistance. They are in what is known as aquatic distress. They are not drowning, but realize they are in trouble and still have the mental capacity (and lung capacity) to call for help.”
Characteristics of the Instinctive Drowning Response
Drowning people are physiologically unable to call out for help, except in rare circumstances. The respiratory system was designed for breathing. Speech is the secondary or overlaid function. Breathing must be fulfilled, before speech occurs.
Drowning people’s mouths alternately sink below and reappear above the surface of the water. The mouths of drowning people are not above the surface of the water long enough for them to exhale, inhale, and call out for help. When the drowning people’s mouths are above the surface, they exhale and inhale quickly as their mouths start to sink below the surface of the water.
Drowning people cannot wave for help. Nature instinctively forces them to extend their arms laterally and press down on the water’s surface. Pressing down on the surface of the water, permits drowning people to leverage their bodies so they can lift their mouths out of the water to breathe.
Drowning people cannot voluntarily control their arm movements. Physiologically, drowning people who are struggling on the surface of the water cannot stop drowning and perform voluntary movements such as waving for help, moving toward a rescuer, or reaching out for a piece of rescue equipment.
People’s bodies remain upright in the water, with no evidence of a supporting kick. Unless rescued by a trained lifeguard, these drowning people can only struggle on the surface of the water from 20 to 60 seconds before submersion occurs.
(Source: Coast Guard On Scene Magazine)