The World Health Organization in 2005 defined<unk>  as "the process of experiencing respiratory impairment from submersion/immersion in liquid." This definition does not imply death or even the necessity for medical treatment after removing the cause, nor that any fluid enters the lungs. The WHO further recommended that outcomes should be classified as death, morbidity, and no morbidity. There was also consensus that the terms wet, dry, active, passive, silent, and secondary<unk>  should no longer be used. Experts differentiate between distress and<unk> . * Distress – people in trouble, but who can still float, signal for help, and take action. *<unk>  – people suffocating and in imminent danger of death within seconds. Forensics Forensic diagnosis of<unk>  is considered one of the most difficult in forensic medicine. External examination and autopsy findings are often non-specific, and the available laboratory tests are often inconclusive or controversial. The purpose of an investigation is generally to distinguish whether the death was due to immersion or whether the body was immersed postmortem. The mechanism in acute<unk>  is hypoxemia and irreversible cerebral anoxia due to submersion in liquid.<unk>  would be considered a possible cause of death if the body was recovered from a body of water, near a fluid that could plausibly have caused<unk> , or found with the head immersed in a fluid. A medical diagnosis of death by<unk>  is generally made after other possible causes of death have been excluded by a complete autopsy and toxicology tests. Indications of<unk>  are seldom completely unambiguous and may include bloody froth in the airway, water in the stomach, cerebral edema and petrous or mastoid hemorrhage. Some evidence of immersion may be unrelated to the cause of death, and lacerations and abrasions may have occurred before or after immersion or death. Diatoms should normally never be present in human tissue unless water was aspirated. Their presence in tissues such as bone marrow suggests<unk> ; however, they are present in soil and the atmosphere, and samples may easily be contaminated. An absence of diatoms does not rule out<unk> , as they are not always present in water. A match of diatom shells to those found in the water may provide supporting evidence of the place of death.<unk>  in saltwater can leave significantly different concentrations of sodium and chloride ions in the left and right chambers of the heart, but this will dissipate if the person survived for some time after the aspiration, or if CPR was attempted, and have been described in other causes of death. Most autopsy findings relate to asphyxia and are not specific to<unk> . The signs of<unk>  are degraded by decomposition. Large amounts of froth will be present around the mouth and nostrils and in the upper and lower airways in freshly drowned bodies. The volume of froth is generally much greater in<unk>  than from other origins. Lung density may be higher than normal, but normal weights are possible after cardiac arrest or vasovagal reflex. The lungs may be overinflated and waterlogged, filling the thoracic cavity. The surface may have a marbled appearance, with darker areas associated with collapsed alveoli interspersed with paler aerated areas. Fluid trapped in the lower airways may block the passive collapse that is normal after death. Hemorrhagic bullae of emphysema may be found. These are related to the rupture of alveolar walls. These signs, while suggestive of<unk> , are not conclusive.
Drowning
Arrhythmia
Heat stroke
Hypoglycemia
Sudden wealth syndrome
Murder
Heat exhaustion
Seizure