An intensive care consultant wrote a letter to his wife titled "In case I die" at the start of the coronavirus outbreak.
Matt Morgan said the letter was not meant to instill fear but he wrote it because of the uncertainty surrounding the disease.
He also left his passwords and the location of important documents for his wife to access easily.
Mr Morgan, who is also the research and development lead for Critical Care at University Hospital of Wales, wrote: "I have had a bloody wonderful life, travelled, partied, had two amazing children, spent time with friends, family, and done things I never dreamed of.
"I love my job even though it can be hard and dangerous.
"Touching the lives of others is the best feeling in the world."
During the outbreak, his wife Alison, who is a teacher, has been at work to teach the children of other key workers who are still going to school.
Mr Morgan - who is a husband, a father-of-two and a son - previously wrote a letter to older people worried about getting the coronavirus, Wales Online reports.
He said: “I only really wrote that for the people in my family.
“My parents are in their 70s. It was late one night after a busy shift and the news was on in the background.
"What they were saying about the virus didn’t really reassure me as a son, so I wrote that letter.”
Mr Morgan works in Cardiff, a nine-mile drive from his home in Sully.
A month ago, in the unit where he works there was only one patient with coronavirus, but now it's full - almost exclusively with Covid-19 patients.
The consultant said: “The last four weeks have felt like four months.
"We are looking after the most critically ill patients and they are almost exclusively there because of Covid.
"The hospital now is unrecognisable - we have expanded the number of beds, there are new staff helping out.
"But what has changed the most is that there aren’t any family around.
"The corridors are usually buzzing with family and loved ones, but now they are empty.”
But life in the critical care unit is calm, he added. “Of course there are challenges - we are looking after more patients than we have ever looked after.
"But we have more equipment from other areas - the dental school or pediatrics-and we do have capacity and room for more patients.
"We do have space for critically ill patients, whether they be Covid-related or not.
“It doesn’t feel chaotic. Our role in ITU is to bring a pool of calm to a sea of chaos."
Matt said he regularly keeps in touch with colleagues in other countries.
He added: “We did learn lessons from China and Italy which gave us a head start in what would work.
“Right now, the international community talk to each other all the time via WhatsApp and email.
"Doctors from China and Italy share advice on equipment, such as the fact you can use one ventilator for multiple patients.
"They also help on the human level, with counsel that this is a marathon, not a sprint, and tips on how to speak to families.”
He also said kind gestures such as food donations and people clapping help him go through his long 13-hour shifts.
He said taking the kit off is very important: “When I leave this room, I remove my sweaty, uncomfortable protective clothing - gown, gloves, and a specific mask which filters viruses.
"If I do things in the wrong order, or touch my face with my hands, the greatest mask in the world will not save me.
"I take my mask off at the back, throw in in the bin with one smooth motion, and wash my hands.
"We developed this method during the Ebola scare, and use in now during seasonal flu outbreaks. It takes practice, and staff need training.”
Matt admitted it is hard to support the patients who have no family next to them.
He explained: "Family are as much part of things too, and critical care is stressful for family members as well as the patients.
"I speak to the patient’s family on the phone: it isn’t safe for them to come to the hospital.
"It’s difficult enough talking to the relatives of a critically ill person, even when you are able to look in their eyes.
"The only way to handle this is to be honest. 'Your relative is sick enough to die,' I say to them. 'But our passion in life is getting your loved one better, and back to you.'
"I like to call it ‘honest hope'."
