I've received several e-mails about a child who died from a drowning several hours after his submersion event. The event is being called a parking lot or secondary drowning. With drowning in general, a patient has three chances to die.
First, to drown means death after submersion and a loss of consciousness. Since you can't breathe underwater, your only chance of survival after you lose consciousness and stop breathing is rapid extrication followed by outstanding BLS and ALS care. If you aren't successfully resuscitated, you have drowned (cause of death #1).
Even if you're successfully resuscitated after a loss of consciousness underwater, you aren't in the clear yet. Patients who had water flow into their lower airway passages and through the alveoli can experience a rapid and worsening onset of pulmonary edema. The accumulation of edema obstructs oxygenation of red blood cells. This is sometimes known as a parking lot, or secondary, drowning. The patient's condition could rapidly deteriorate over several hours, eventually leading to death (cause of death #2).
If you survive the submersion and the edema, your prognosis is still as murky as a barnyard puddle. The infection likely to proceed from water and emesis aspiration -- assume all patients will vomit during resuscitation -- is high. Death can result from the ensuing infection (cause of death #3).
Our best defense against drowning is prevention. The following are simple rules for drowning prevention.
- Know your limits.
- Learn to swim.
- Swim with a buddy.
- Do not mix swimming and boating with drugs and alcohol.
- Wear a personal flotation device when using small boats.
- Monitor children in or near water.
- Block child access to pools.
- Do not play breath-holding games.
If a patient has lost consciousness after submersion, they need rapid extrication, outstanding BLS, rapid ALS interventions on scene, transport to a hospital equipped to deal with the immediate, short-term, and long-term complications, and a lot of luck. Remember, patients who don't have a pulse back by the time they reach the emergency department don't survive.