Most common cause of death in drowning is:
Ans) b (Hypoxemia) Ref: K.S. Narayan Reddy 21st EdnCommon cause of death in drowning is due to asphyxia. Asphyxia can lead to anoxia, hypoxia.Other causes include vagal inhibition, ventricular fibrillation, laryngeal spasm.A conscious victim will hold his or her breath and will try to access air, often resulting in panic, including rapid body movement. This uses up more oxygen in the blood stream and reduces the time to unconsciousness. The victim can voluntarily hold his or her breath for some time, but the breathing reflex will increase until the victim will try to breathe, even when submerged.The breathing reflex in the human body is weakly related to the amount of oxygen in the blood but strongly related to the amount of carbon dioxide. During apnea, the oxygen in the body is used by the cells, and excreted as carbon dioxide.Thus, the level of oxygen in the blood decreases and the level of carbon dioxide increases. Increasing carbon dioxide levels lead to a stronger and stronger breathing reflex, up to the breath-hold breakpoint, at which the victim can no longer voluntarily hold his or her breath. This typically occurs at an arterial partial pressure of carbon dioxide of 55 mm Hg, but may differ significantly from individual to individual and can be increased through training.In fresh water and brackish water drowning the aspirated water is rapidly absorbed from the alveoli into the circulation producing an expansion of blood volume,haemodilution and haemolysis.Circulatory overload, hyponatraemia and sodium/potassium imbalance together with myocardial hypoxia resulted in a dramatic collapse of systolic pressure quickly followed in the majority of cases by ventricular fibrillation.In salt water drowning the aspiration of water results in withdrawal of water from the pulmonary circulation into the alveolar spaces as a result of the osmotic differential while at the same time, electrolytes (sodium, chloride, magnesium) pass into the blood.There is haemo-concentration but not haemolysis and little change in the sodium/potassium balance. In both fresh water and salt water drowning there is terminal pulmonary oedema.
Hypocapnia
Hypoxemia
Hypothermia
Hypoglycemia
Asphyxial Deaths