Think you've had a bad day at the dentist?
Meet the tiger whose heart STOPPED while having a filling
Even the biggest creatures can be humbled by a toothache.
Vets had to perform CPR on a 160kg Siberian tiger after she suffered a cardiac arrest during a visit to the dentist.
Sayan was undergoing root canal surgery when she suffered a rare reaction two hours into the procedure.
Quick thinking medics at Yorkshire Wildlife Park gave the three-year-old heart massage and two shots of adrenaline and brought her back to life.
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Sayan is now recovering from the traumatic dentist experience.
Vet Alan Tevendale, 31, said: 'We noticed a change two hours into the operation and found no pulse or heart beat.
'We then immediately started cardiac massage and gave a shot of intravenous adrenaline. When this didn't work we had to give another shot of adrenaline directly into the heart whilst we continued cardiac massage.'
'When I checked again she had a pulse and heartbeat.
'Gradually, she returned to a steady rhythm. After five minutes we took her off ventilation and she managed to breathe herself.
The Siberian (amur) tiger
Adult size: 10.75ft (3.3m) Adult weight: 660lb (300kg)
Protection status: Endangered
The Siberian Tiger (also called the amur) is the largest big cat in the world. They live primarily in eastern Russia's birch forests, though some exist in China and North Korea. There are an estimated 400 to 500 remaining in the wild, making them an endangered species.
'This is very rare and was extremely stressful – the most stressful experience of my life. We are all so relieved she is now ok.'
Sayan, who weighs around 160 kilos, had been acting grumpily and keepers at the wildlife park in Doncaster decided to get her teeth examined in case they were causing her discomfort.
A specialist dentist was called in last week to examine the tiger’s teeth
After a full check up he opted to perform a root canal filling to a lower canine.
But the operation which should have been straightforward took a dramatic twist.
'There is always a risk with anaesthetics but I have not seen this reaction in a tiger in 27 years and I have worked on hundreds of big cats.,' said dentist Peter Kertesz, who has a practice in Central London.
'The good thing is that we had the expertise to cope with the emergency and, although her heart stopped for seven to ten minutes, Sayan was in good hands and she has made a great recovery.'
Sayan came to Yorkshire Wildlife Park to live in Land of the Tigers last year as part of the Siberian Tiger Breeding Programme.
Fewer than 400 Siberian tigers are left in the wild because of habitat loss and poachers.
She had been kept in a separate but adjacent enclosure to three year-old male Vladimir for eight months while they got acclimatised to each other before being introduced on Valentine’s Day.
Yorkshire Wildlife Park director Cheryl Williams said: 'We are extremely grateful for the expertise and speed of the whole medical team.
'They were brilliant in bringing Sayan back to life.'
'The welfare of our animals is our highest priority and I am delighted to report that Sayan is now back in the Land of The Tigers and seems much better tempered!'
Big cat: Siberian tigers are the world's largest cat. There are only an estimated 400 left in the wild
By IAN GARLAND
PUBLISHED: 08:09 EST, 25 May 2012 | UPDATED: 11:54 EST, 25 May 2012