The art of drowning

[DM]

For those of you are going to drown this season, here are a few factoids so you know what is happening.

On average, every year, around 500 people drown in England and Wales, 17 percent in the sea, the rest inland, baths, swimming pools etc. Many are competent swimmers.

Prolonged Immersion Collapse.

When a victim has been immersed for some time, floating vertically, water exerts a pressure on the legs which in turn massages the veins. This maintains an adequate return of venous blood to the heart. When rescued, this pressure is lost and gravity prevents blood returning to the heart causing a sudden drop in blood pressure resulting in a faint or even sudden death. To counter this, lay the victim flat and raise his legs. This is called autotransfusion and returns 2 litres of blood to the core system thereby helping to maintain blood pressure.

More to follow......

[Manos]

Very interesting indeed. Post some more

[DM]

Immersion into cold water, causes a sharp intake of breath resulting in panic breathing and frequent submersion. Compounded by respiratory distress, compromised buoyancy causes the victim to sink, at the same time, swallowing large volumes of water. In cold water, even strong swimmers may not be able to coordinate breathing and the muscular action of swimming. In these circumstances, water is prevented from entering the lungs by repeated swallowing and laryngeal spasm. This causes a loss of oxygen in the blood. (hypoxaemia) resulting in unconsciousness and eventually death. Water enters the lungs only at the point of death when the larynx relaxes. Drowning can be categorised under five headings.

near drowning
dry drowning
fresh water drowning
salt water drowning
secondary drowning

more to follow.........

[DM]

Near Drowning

If a victim is rescued before the point of death, or there is temporary survival, this is described as near drowning.

Dry drowning. (about 10 percent of cases)

As the victim sinks, and unconsciousness deepens, they continue to try and breathe. The impact of the incoming water stimulates the reflex which triggers the larynx and epiglottis to close. With the lungs protected by the epiglottis, water is diverted to the stomach. In most cases of drowning, only one litre of fluid has entered the lungs compared with several litres swallowed.

Fresh water drowning.

A volume of water entering the lungs interferes with the passage of gases between the lungs and bloodstream. This results in haemodilution (Dilution of the blood) and an interference in the acidity(ph) levels of the blood. Under these circumstances, a cardiac arrest may occur 2- 5 minutes after rescue.

more to follow.........

[DM]

Salt Water Drowning

This has the opposite effect of fresh water drowning but the same result. Salt water entering the lungs is more solute than blood, therefore water is drawn into the lungs increasing the volume of fluid therein. This, in turn, increases the viscosity of the blood causing sluggish circulation which slows the heart rate to the point of cardiac arrest. This may occur up to 12 minutes after rescue.

Secondary Drowning

Where a drowning victim has been successfully rescued/resuscitated, they may appear to be fully recovered. However, if water has entered the body, rapid absorption will take place, from the stomach into the blood stream, distorting the ph balance of the blood. Death could occur up to 72 hours later. In the case of salt water, residual water in the lungs draws fluid from the blood stream causing pulmonary oedema (shocked lung syndrome) This may occur many hours after rescue.

more to follow.......

[Manos]

Hope you don't mind me copying and saving your thread about drowning. Is good reading.

[DM]

Mammalian Diving Reflex.

This reflex is little understood and is particularly active in the very young. If a victim is plunged into cold/icy water face first, the result is a near total shutdown of the respiratory, circulatory and nervous systems to a point of suspended animation or apparent death. Victims of this phenomena have been known to recover after 38 minutes submerged and sixteen hours of resuscitation. The moral of this is to never give up resuscitating a drowning victim no matter how dead they look.

more to follow.......

[narked]

Freedivers make use of the diving reflex. The reflex does not take effect instantly, so you may need to spend some time in the water before it kicks in, but it helps to reduce your heart rate amongst other things, making the air in your lungs last slightly longer. But as said, not much is known about it's true nature.

Matt

[Manos]

I'm following this bit by bit LOLOL

[DM]

The Management of Drowning victims.

Ensure an open airway. Commence CPR, checking for pulses in two places, especially if hypothermia is present
To prevent the risk of post immersion collapse, lift the victim from the water horizontally if possible. Place the victim head down, feet raised and do not allow them to walk. Consider the possibility of spinal trauma.

DO NOT....

apply direct heat to a hypothermia victim, wrap in a space or hypothermia blanket. After prolonged immersion, warming should be a gradual process, however, if immersion was for a short period and the body's core temperature is unaffected, rewarming is less critical and can be carried out quicker.
Hypothermia must be considered in all cases of immersion in cold water. This is a serious complication of drowning which can mimic signs of cardiac arrest e.g. dilated pupils, imperceptible pulse and respirations

more to follow........