And since this thread was posted, CPR has changed, for this very reason.
Now, unless you’re a medical professional (lifeguards are not) WITH appropriate safety equipment on you, CPR is “hands only”. Compressions to the chest, that’s it. No mouth to mouth, no rescue breaths. Turns out it’s more useful to circulate the oxygen that’s already in the system, rather than try to introduce more.
This is even MORE true, I believe, in a near-drowning case, when the lungs are presumably full of water and oxygen from rescue breaths would be unable to reach the alveoli anyhow.
Now, if you’re* trained in* conventional CPR and you have your mouthguard with you, it’s still best for children ages 1-8. If you don’t have your mouthguard with you, then it’s your call. But compression only CPR is better than nothing, even for children, and requires no equipment.
So…if you see a 3 year old in the water unresponsive, you pull her out, you call 911 (or whatever Emergency Number works in your area) and you pump on the center of her chest between the nipples, 2 inches deep (that’s 1/3 the depth of the chest cavity, deeper than most people think), to the beat of “Staying Alive”. That’s it. Easy peasy. (If you’re on a loose sand beach, you can put a hardcover book under her back to make it easier to push.)
When she starts to throw up, by the way, quickly roll her to one side so she doesn’t breathe the vomit/water back in. As soon as she’s done throwing up, see if she’s breathing now. If so, you’re done. If not, begin pushing again. Continue until help arrives.
(And I have absolutely no judgement against those lifeguards from 6 years ago, for the reasons already articulated here by medical professionals. I have a lot of anger against whomever hired those lifeguards, though, for not making sure they had all the training and gear they needed to do their jobs.)