Dog owners are being urged to learn how to perform the 'kiss of life' on their pets as experts warn that extreme temperatures can trigger life-threatening emergencies.

With Britain sweltering through its hottest May on record, vets say knowing how to give a dog CPR could make the difference between life and death if a pet collapses during hot weather.

Heat stroke is one of the leading causes of cardiac arrest in dogs during periods of high temperatures. 

Research from the Royal Veterinary College found that one in four dogs treated for heat-related illnesses does not survive.

Veterinary surgeon Dr Emma Chandley, who works with pet insurance company Petgevity, said many owners would know what to do if a person stopped breathing, but far fewer realise similar techniques can be used on animals.

'Acting fast in these situations, to keep air and blood circulating through the dog's body, could be what buys you enough time to reach a vet for the medical help they need,' Dr Chandley told The Telegraph.

'Having the basic knowledge can be very useful as early intervention before reaching a vet could be lifesaving.'

The warning comes after temperatures climbed to 35.1C at Kew Gardens in west London on Tuesday as the UK recorded its warmest May since records began.

Experts say the signs of a dog suffering a cardiac arrest are similar to those seen in humans. 

Owners should look for an animal that is unresponsive, not breathing normally, or has no detectable pulse or heartbeat.

However, there are several important differences when carrying out CPR on a pet.

Unlike humans, rescue breaths should be delivered through a dog's nostrils rather than its mouth. 

Owners should also check for a femoral pulse on the thigh, rather than feeling for a pulse in the neck or wrist.

According to guidance from the People's Dispensary for Sick Animals (PDSA), dogs should generally be laid on their right-hand side before CPR begins. 

Flat-chested breeds, including British Bulldogs, should instead be placed on their backs.

Owners should position their hands over the dog's heart and administer 30 chest compressions at a pace of around two per second - roughly matching the rhythm of the Bee Gees hit Stayin' Alive. 

This should be followed by two rescue breaths through the nose.

The cycle of 30 compressions and two breaths should continue for two minutes before checking for signs of a heartbeat. 

If there is still no heartbeat, CPR should be continued while arrangements are made to get the animal to a vet.

Dr Chandley stressed that emergency first aid should never replace professional treatment.

'It's important to also note that immediate veterinary care is still essential, even if the dog appears to recover, as the underlying cause still needs urgent treatment,' Dr Chandley said.

The RSPCA echoed the warning, saying that while first aid may help save an animal's life, 'it should never be considered a substitute for professional veterinary treatment'.

The charity added that CPR was 'not a guaranteed solution' and that owners 'should always call your vet first, or have someone call if you're trying first aid'.

For dogs suffering from heat stroke, the RSPCA recommends pouring cold water over the animal's body, avoiding the head, before transporting it to a veterinary clinic.

Some breeds are particularly vulnerable to heat-related complications and heart problems.

King Charles Cavalier Spaniels are known to be more prone to conditions including mitral heart disease, heart murmurs and leaky heart valves, all of which may require medication.

Dobermans are also considered higher risk because of their susceptibility to dilated cardiomyopathy, a disease that can lead to sudden cardiac arrest.

Meanwhile, breeds already prone to breathing difficulties, such as bulldogs and pugs, face additional dangers during hot weather.

Cats can also receive CPR if necessary. Vets advise ensuring the animal is unconscious before attempting rescue breaths through the nose to reduce the risk of being scratched.

As with dogs, cats should be placed on their side before receiving 30 chest compressions followed by two rescue breaths.

Interest in pet first-aid training has surged in recent years, with a growing number of veterinary practices offering dedicated courses. 

Online classes typically cost between £20 and £50, while face-to-face sessions can cost up to £100.

The Met Office said temperatures in London are expected to remain above 20C until Tuesday, although much of the country is forecast to see rain and cloud this weekend as the record-breaking heat gives way to more unsettled conditions.