Living around the lake with the recent low temperatures we’ve experienced lately makes it important to review how to survive immersion in cold water.
During exercise and high temperatures, our body dissipates heat by sweat and evaporation. Similarly, when immersed in cold water, the body loses heat through the contact of water with the skin. As surrounding water sucks heat away from the body, hypothermia (the lowering of the body’s core temperature) sets in, we become weak and lethargic, and we can quickly drown.
When the face is immersed in water that is seventy degrees Fahrenheit or less, the MDR (mammalian diving reflex) kicks in. So how does the MDR help us survive? The body automatically slows down our respiration and heartbeat to where they are nearly undetectable, constricts the muscles in our extremities, and directs oxygen-laden blood to our brain and critical organs. This is more pronounced in infants and children, where there have been cases of resuscitation after 40 minutes of submersion. In adults, survival for 25 minutes is possible.
There’s more to this story in the current issue of the Smith Mountain Eagle newspaper. Pick up a copy or subscribe at www.smithmountaineagle.com/subscriber_services to view the full article in the print and/or e-edition version.