In fact, drowning is the most likely cause of unintentional death in this population. Consumption of alcohol clearly increases the risk of drowning. Alcohol use is most likely in male, suicidal, boat or motor vehicle related, and off-season drownings. Although it adversely affects judgment and has multiple physiologic effects upon the body, alcohol s lethality may lie in its ability to induce or promote abnormal heart rhythms, which cause sudden cardiac arrest in submersion victims. Unfortunately, the mechanism attempting to keep water out of the lungs also interferes with the ability to breathe.
Water plays a limited role once the victim can no longer breathe.
Water washes out surfactant, a substance that allows our lungs to inflate easily and fully. Once this occurs, the smaller airways of the lungs collapse, further reducing the ability to breathe. Lack of oxygen lasting one to three minutes can shut down key organ systems, especially the brain and the heart. The victim loses consciousness, and the heart develops arrhythmias, leading to cardiac arrest. The most common and dreaded event following a severe drowning is the swelling of brain tissue resulting from damage caused by lack of oxygen during the submersion event.