Module 3.2
What drowning actually is
Drowning is consistently misrepresented — by films, by bystanders, and sometimes by people who haven't been trained in water rescue medicine. On a SAR vessel, that misunderstanding can cost a life. This module covers what actually happens physiologically during drowning, how to recognise someone who has been in the water long enough to be in danger, and the immediate steps that make a difference before your medical team takes over.
Most crew aboard a SAR vessel will never need to perform CPR — the medical team handles clinical interventions. But understanding the physiology and knowing the immediate reception priorities makes every crew member more effective when survivors arrive.
Medical team leads clinical care
On all SAR vessels with a medical team, clinical management of drowning casualties is the medics' responsibility. This module is designed to make non-medical crew aware of what is happening and why — not to train you to perform medical procedures. Follow your organisation's SOPs and your medical team's direction at all times.
What you'll cover
- What drowning is — and the common misconceptions about how it looks
- The physiological stages — what happens to the body during submersion
- Why resuscitation decisions are made by the medical team, not general crew
- The immediate crew response when a drowning casualty comes aboard
- The most dangerous myths about drowning treatment — and why they persist
Estimated time
10 minutes — followed by a knowledge check
Section 1 of 3
What happens to the body
The World Health Organisation defines drowning as respiratory impairment from submersion or immersion in liquid. That definition matters — drowning is not just about being underwater. It is about the airway, and what happens when water enters it.
The process unfolds in stages. Understanding these stages helps crew recognise the severity of a situation and communicate effectively with the medical team.
01
Breath-holding
Initial submersion triggers an instinctive breath-hold. The person may struggle and thrash. This stage is brief — typically 20–60 seconds. It is the stage most associated with the visible splashing seen in films, but it ends quickly.
02
Laryngospasm
As the breath-hold breaks, the larynx (the part of the airway just above the windpipe) reflexively spasms shut to prevent water entering the lungs. In some cases this prevents significant aspiration — but it also stops breathing entirely. This is sometimes called "dry drowning."
03
Water aspiration
As oxygen depletes, the laryngospasm relaxes and water is inhaled into the lungs. Even small amounts disrupt the lubricating substance (surfactant) that helps the lungs open and close, causing breathing failure.
04
Hypoxic arrest
Low oxygen levels (hypoxia) cause loss of consciousness and, if not interrupted, cardiac arrest — the heart stops. Speed depends on water temperature, the person's fitness, and whether they were able to keep their airway clear at any point.
Cold water and survivability
Cold water protective effects in cardiac arrest require water temperatures approaching 0°C and extremely rapid cooling — conditions that do not exist in the Mediterranean, which reaches around 15°C at its coldest. Do not assume cold water provides a protective benefit in this context. If a person is in cardiac arrest and was recently seen alive, resuscitation is attempted if resources allow — this decision is made by the medical team on a case-by-case basis.
What drowning actually looks like
Most drowning does not look like drowning in the media sense — thrashing, screaming, arm-waving. In reality, drowning people are usually quiet and vertical. They are using all their available physical effort to stay at the surface and breathe. They cannot call for help and cannot wave. They may slip beneath the surface while appearing merely to be treading water. Look for: head low in the water, mouth at or near water level, eyes unfocused or closed, no forward progress, not using legs effectively.
Section 2 of 3
Immediate response when a drowning casualty boards
If a survivor is recovered having been in the water for any significant time, or appears unresponsive or distressed, the following priorities guide the immediate crew response before and during handover to the medical team.
1
Alert the medical team immediately. Do not wait to assess the patient yourself. Call for medical support the moment any survivor shows signs of unresponsiveness, laboured breathing, blue or grey lips, or altered consciousness. Time matters above all else.
2
Maintain horizontal positioning during extraction where possible. Do not stand a drowning casualty up or seat them upright. The cardiovascular system has adapted to the pressure of immersion — sudden positional change can cause a significant drop in blood pressure. Horizontal or semi-horizontal until the medical team directs otherwise. In situations where horizontal extraction is not possible due to vessel layout or urgency, move the person as quickly as possible to horizontal once aboard.
3
Do not attempt to drain water from the lungs. This is a dangerous and medically unsupported intervention. It delays getting oxygen to the patient, risks the person inhaling vomit, and can cause internal injury. If the patient is breathing, position them in the recovery position. If not breathing, this requires CPR and airway management by trained personnel only.
4
Begin warming immediately. All drowning casualties should be treated as hypothermic until assessed otherwise. Remove wet clothing, provide blankets or a survival bag, and move to a sheltered area. Hypothermia and drowning frequently co-occur in the Mediterranean context.
5
Monitor for secondary drowning. A survivor who appears recovered may deteriorate hours later. Secondary drowning occurs when inhaled water causes fluid to build up in the lungs (the medical term is delayed pulmonary oedema). Symptoms include increasing shortness of breath, fatigue, and cough. Any survivor who was submerged should be monitored and any deterioration reported to the medical team immediately.
Do not attempt abdominal thrusts or "water removal" manoeuvres
Heimlich-style manoeuvres are not recommended in drowning treatment and are potentially harmful. They can cause internal injury, delay ventilation, and provoke vomiting with subsequent aspiration. The Wilderness Medical Society, ILCOR, and the European Resuscitation Council are all clear on this. If you encounter anyone attempting this on a survivor, alert the medical team.
Section 3 of 3
Common myths — and why they matter
Several persistent myths about drowning are not just inaccurate — they lead to harmful interventions and delayed appropriate care. Crew members who understand these myths are better equipped to support the medical team and avoid well-intentioned but counterproductive actions.
Myth
"You can tell someone is drowning because they're waving and shouting." In reality, most drowning people cannot call for help. They are in an instinctive survival response — they cannot voluntarily wave or shout because doing so would submerge them further.
Fact
Drowning is usually silent and vertical. Look for: head low in the water, mouth at or near water level, eyes unfocused or closed, hair over forehead, not using legs, no forward progress despite effort.
Myth
"If they're conscious, they're fine." Survivors who appear conscious and responsive may still have aspirated significant water and face risk of deterioration in the hours following rescue.
Fact
Secondary drowning — fluid building up in the lungs — can develop hours after rescue in survivors who seemed initially well. All survivors who entered the water should be medically assessed, not just those who appeared distressed at recovery.
Myth
"You have to get the water out of them first." Turning a non-breathing patient upside-down or performing abdominal thrusts delays the only intervention that can save them — oxygenation.
Fact
Water in the lungs is a clinical problem managed by the medical team. Your job is to keep the patient positioned correctly, keep them warm, and ensure rapid medical handover. Never attempt to "drain" a drowning patient.
Myth
"If too much time has passed, there's no point trying." In cold-water environments (near 0°C), cold water can have a protective effect. In the Mediterranean, water temperatures are never cold enough for this to apply. Whether to attempt resuscitation is always a medical decision.
Fact
In water rescue, resuscitation efforts continue until the patient is warm and unresponsive to resuscitation. The decision to cease resuscitation is always made by medical personnel, not by general crew.