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Elizabeth John said the letter was like a "reaper's death sentence"
GP surgery apologized after sending a letter asking patients with life-limiting illnesses to complete a "do not resuscitate" form.
A letter from Llynfi Surgery, Maesteg, asks people to sign to ensure that emergency services are not called if their condition worsens due to the coronavirus.
"We are not going to abandon you. But we have to be frank and realistic," he said.
One patient said she left her feeling "worthless". Cwm Taf's health council issued an apology for the surgery.
A copy of the letter was tweeted
The letter says that, in an "ideal situation", the doctors would have talked in person, but had written to them because they feared they were carrying the virus and were asymptomatic.
"Completing a DNACPR will have several benefits," said the letter.
"1 / your GP and, more importantly, your friends and family will know not to call 999. 2 / scarce ambulance resources can be targeted at young people and in good shape who have a greater chance".
According Guardian's Journal, the letter was sent to a small number of patients and the surgery team was apologizing directly to the recipient.
Patient Elizabeth John, who has vaginal cancer that spreads to the lungs and is incurable, said the letter caused "great distress" for the family.
Elizabeth John was one of the patients who received a letter
"With treatment, my cancer can be kept away, so I am not ready to dig my grave, despite being a burden on society," she said.
"This letter made me feel worthless and I felt like I had received a death sentence from the reaper."
But the 61-year-old man, who has had the disease for eight years, added: "If there is the option of a 20-year-old with a fan and me with a fan, of course I would give that 20-year-old that fan . "
Cwm Taf said the board was not a recommendation from the health board.
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"The surgery was informed that the letter caused inconvenience to some of the patients who received it," said a statement.
"That was not their intention and they apologize for any suffering caused. The surgery staff are talking to the patients who received the letter to apologize directly and answer any concerns they may have."
Ogmore deputy Chris Elmore, whose constituency covers Maesteg, said: "There is no way around this content, it is deeply worrying."
"The member of the Wales Assembly in Ogmore, Huw Irranca-Davies, and I were informed of this on Monday night. We went straight to the health council to find out what had happened.
"The council investigated and it was not a standard letter, so the health council spoke directly with the surgery.
"They have now asked the surgery to contact the patients who received the letter to apologize and, most importantly, to offer appropriate advice on what could really happen in the circumstances of their specific health conditions."
"We are very concerned about the stress it has caused."
Helena Herklots, People's Commissioner for Wales, said she was "shocked" by the letter.
"This is shameful and unacceptable," he added.
"Although difficult and painful decisions need to be made in the coming weeks, they must be made on a case-by-case basis, through honest discussions between patients, doctors and their families who consider risks and benefits, as well as the people themselves." wishes."