PATHOPHYSIOLOGY  OF  DROWNING

Drowning occurs when water fills the airways for any reason. It is important to note that progressive aspiration of water can result in hypoxemia. If loss of consciousness occurs, the continued hypoxemia can result in bradycardia and cardiac arrest. In the lungs, aspiration can cause a washout and destruction of alveolar surfactant resulting in severe hypoxia, alveoli derecruitment, reduced pulmonary compliance and noncardiogenic pulmonary edema, all of which can complicate ventilator management. It should also be noted that there is no such thing as “Near Drowning.” Correct terminology includes “Non-Fatal Drowning” and “Fatal Drowning.”

Immersion in water when associated with panic, exhaustion, inadequate water competency, a medical emergency such as lethal cardiac dysrhythmia or seizure, or effects of hypo/hyperthermia can lead to drowning from one of the following mechanisms:10-15