Last year, the U.K.'s St John Ambulance launched The Chokeables, an animated PSA that used humor to educate the public about how to save a choking baby. According to the charity, it's been a big success, with 46 children's lives saved as a result of the campaign.

The same tactic is repeated is its latest video, by BBH London, this time on how to resuscitate a baby giving CPR.

The animated campaign, aimed at women with children under three, portrays some well-known nursery rhyme characters-- Incy Wincy Spider, Humpty Dumpty, Jack and Jill, and the Cat and the Fiddle -- working at Nursery Rhymes, Inc. and trying to create a memorable rhyme to explain the technique. They struggle to find anything that rhymes with "ambulance," but they eventually settle on a catchy song, albeit with some terrible rhyming. The campaign, which features the voices of comedians Adam Buxton and Tim Key, was animated by Becky Sloan and Joseph Pelling at Blinkink.

As with the previous PSA, the serious subject matter and light-hearted tone might seem rather a clash -- but it's clearly a technique that works.

Ian Heartfield, creative director at BBH London, said in a statement: "Baby CPR is a difficult and scary thing to talk about. No one wants to think about it, let alone learn it. So we have to do everything we can to make people sit up and take notice. We hope that puppeteered nursery rhyme characters on the brink of a nervous breakdown will do the trick."