Let's establish the terms that are currently used worldwide in the medical field. The following is readily available on UpToDate. 

The use of outdated terms such as "near-drowning," "secondary drowning," "wet drowning," and "dry drowning" is discouraged. Instead, the following definitions are recommended for clarity and accuracy:

• Drowning: Defined as "the process of experiencing respiratory impairment from submersion or immersion in liquid."
• Fatal Drowning: Describes a drowning event that results in death.
• Non-fatal Drowning: This term describes a situation where a drowning event is interrupted before it leads to death, allowing the victim to survive. According to a classification by the World Health Organization, non-fatal drowning is categorized based on the severity of respiratory impairment observed immediately after the incident has ceased:
  • Mild Impairment: The individual is fully alert, breathing normally but may exhibit involuntary distressed coughing.
  • Moderate Impairment: The victim experiences difficulty breathing, may appear disoriented, but remains conscious.
  • Severe Impairment: The person is either unconscious or not breathing, indicating critical respiratory distress.

A non-fatal drowning can result in nothing more than a cough, a short period of difficulty breathing, vomiting, and shivering. More serious injuries can present with hypothermia, persistent difficulty breathing, hypoxia, and respiratory and cardiac arrest.

If a patient is still in the water on arrival, remember that your first priority is your personal safety and the safety of your crew. Look for dangerous situations that may have led to the patient drowning in the first place. Assessing the quality of the water and the container it is in will clue you into most potential hazards.

The recommended water rescue model:
Reach- if the victim is close enough to shore. You can use an oar, pole, branch, or another rescue device if you can't reach them with your hand. 
Throw- a flotation device attached to a rope so the victim can be pulled to shore.
Row- if the previous methods are unsuccessful or the pt is unconscious, trained rescuers should row out to the pt if a boat is available. 
Go- if a boat is unavailable and the reach and throw methods don't work, trained rescuers should go to the pt by wading or swimming. 

Management

The management of a drowning patient is focused on assessing for any co-dominant injury, controlling the ABCs, and preventing further complications.

If the patient is still in the water and you suspect a spinal injury, manually stabilize the neck and spine. If the patient is adequately breathing on his/her own, place him/her in the recovery position and administer oxygen. Use a backboard to roll the victim partially on his/her side so that aspiration can be avoided if the patient vomits; use suctioning as necessary to clear any visible fluids from the airway.

If an AED is available, it is safe to discharge the unit if indicated as long as the patient is not in standing water.

New AHA guidelines advise starting chest compressions and rescue breaths in a 30:2 ratio at a rate of at least 100 compressions/minute, regardless of respiratory status. According to the AHA,

"As soon as the unresponsive victim is removed from the water, the rescuer should open the airway, check for breathing, and if there is no breathing, give 2 rescue breaths that make the chest rise (if this was not done previously in the water). After delivery of 2 effective breaths, if a pulse is not definitely felt, the healthcare provider should begin chest compressions and provide cycles of compressions and ventilation according to the BLS guidelines."

Special aquatic considerations

Beyond drowning, exposure to aquatic environments can result in health conditions that are not seen elsewhere; the most tested of these are decompression sickness, nitrogen narcosis, and barotrauma or "squeeze" injuries. 

Decompression sickness "The Bends" occurs when a SCUBA diver descends to a significant depth and is forced to surface without appropriate decompression stops to allow for nitrogen that dissolves in the blood under high pressure to naturally and slowly percolate out of the blood. This results in gas bubbles forming in the circulation and joints, causing incredibly painful arthralgia and potentially life-threatening respiratory distress. 

Nitrogen narcosis Results from a mix of gas in air tanks that has a high percentage of nitrogen. The symptoms of nitrogen narcosis are largely identical to alcohol intoxication. The management of this condition is limited to the application of oxygen and ruling out the presence of decompression sickness. 

Squeeze injuries are a type of barotrauma that occurs when pressure is placed on the face by a diving mask due to failure to exhale through the nose while diving, causing significant pressure to be placed on the eyes, sinuses, and facial bones. This can result in nosebleeds, eye injury, or sinus damage. Barotrauma refers to tissue damage caused by a difference in pressure between an air-filled space inside the body and the surrounding environment. This often occurs during activities such as diving, flying, or hyperbaric oxygen therapy when rapid changes in pressure are experienced. Common sites of barotrauma include the ears, sinuses, lungs, and gastrointestinal tract. Symptoms can range from mild discomfort and ear pain to severe complications such as ruptured eardrums, sinus injury, pulmonary barotrauma, or even an arterial gas embolism.