The Danger of a Childhood Game We've All Played

Swimming and having fun in the water is part of summer in Australia for many of us. Besides being a great way to cool down on a hot day, swimming is an excellent all-over body workout for people of any age; it tones and strengthens muscles, builds endurance and cardiovascular fitness, improves flexibility, helps us to maintain a healthy weight and reduces mental stress.

Teaching our children to swim is a high priority life skill for most parents and I well remember the sense of relief when all three of my boys achieved a competent level in the water.

Last month on the 29^th January in Wollongong, twelve year old Jack MacMillan drowned in a metre of water in his family’s backyard pool. Jack was a very capable swimmer who loved being in the pool; at the time he was swimming under the supervision of his mother. What could possibly have gone so wrong?

Jack had been enjoying a game most of us have participated in either as children or adults; seeing how many laps he could do while holding his breath and swimming underwater. His mum noticed he had stopped swimming and was lying motionless on the bottom of the pool. Initially thinking he was just mucking around, she quickly realised the situation was much more serious but by then it was too late.

Jack MacMillan died from shallow water hypoxia also known as shallow water blackout (SWB).

Shallow water blackout occurs when the swimmer loses consciousness due to a severe lack of oxygen to the brain. Under normal circumstances our natural inclination to breathe is caused not from a lack of oxygen but from an increase in the levels of carbon dioxide in our bloodstream.

Prolonged or repetitive breath-holding or hyperventilating decreases the amount of carbon dioxide circulating through the bloodstream, slowing down the body’s natural urge to breathe. With a decreased desire to breathe, the underwater swimmer mistakenly believes they are able to hold their breath longer than they safely can. Starved of oxygen, the swimmer loses consciousness without warning and drifts towards the bottom of the pool. With the loss of consciousness the body reacts automatically and recommences breathing, filling the lungs with water. Quietly, without fuss or drawing attention to themselves, the swimmer very quickly drowns.

Prior to hearing the news story on the MacMillan family’s tragic loss of their son Jack, I had never heard of shallow water blackout.

While today may be the official end to summer, locally our warm climate can see us enjoying our swimming well into April. Take the time to talk about shallow water blackout with your family and friends and raise the awareness of the danger of prolonged or repetitive breath-holding in water. One lap down the pool holding your breath might not do you any harm but ongoing laps holding your breath underwater increases your chances of suffering from a potentially fatal shallow water blackout.

More information can be found on the website: www.shallowwaterblackout.org