This cardiac arrest stops the flow of blood and thus stops the transport of oxygen to the brain. Cardiac arrest used to be the traditional point of death, but at this point, there is still a chance of recovery. The brain cannot survive long without oxygen, and the continued lack of oxygen in the blood, combined with the cardiac arrest, will lead to the deterioration of brain cells, causing first brain damage and eventually brain death from which recovery is generally considered impossible. The brain will die after approximately six minutes without oxygen at normal body temperature, but hypothermia of the central nervous system may prolong this.The extent of central nervous system injury to a large extent determines the survival and long term consequences of drowning, In the case of children, most survivors are found within 2 minutes of immersion, and most fatalities are found after 10 minutes or more. Water aspiration
If water enters the airways of a conscious person, the person will try to cough up the water or swallow it, often inhaling more water involuntarily. When water enters the larynx or trachea, both conscious and unconscious people experience laryngospasm, in which the vocal cords constrict, sealing the airway. This prevents water from entering the lungs. Because of this laryngospasm, in the initial phase of drowning, water generally enters the stomach, and very little water enters the lungs. Though laryngospasm prevents water from entering the lungs, it also interferes with breathing.
Geographic tongue, also known by several other terms, is a condition of the mucous membrane of the tongue, usually on the dorsal surface. It is a common condition, affecting approximately 2–3% of the general population. It is characterized by areas of smooth, red depapillation (loss of lingual papillae) which migrate over time. The name comes from the map-like appearance of the tongue, with the patches resembling the islands of an archipelago. The cause is unknown, but the condition is entirely benign (importantly, it does not represent oral cancer), and there is no curative treatment. Uncommonly, geographic tongue may cause a burning sensation on the tongue, for which various treatments have been described with little formal evidence of efficacy. Signs and symptoms
In health, the dorsal surface of the tongue is covered in tuft-like projections called lingual papillae (some of which are associated with taste buds), which give the tongue an irregular surface texture and a white-pink color. Geographic tongue is characterized by areas of atrophy and depapillation (loss of papillae), leaving an erythematous (darker red) and smoother surface than the unaffected areas. The depapillated areas are usually well-demarcated, and bordered by a slightly raised, white, yellow or grey, serpiginous (snaking) peripheral zone. A lesion of geographic tongue may start as a white patch before the depapillation occurs. In certain cases there may be only one lesion, but this is uncommon; the lesions will typically occur in multiple locations on the tongue and coalesce over time to form the typical map-like appearance.