Barbara Darrell thought her life was at an end a few years ago. Doctors had diagnosed stage four COPD. The former smoker’s lungs were so bad she spent her days in bed, hooked up to an oxygen machine, unable to work or care for herself.

Then she connected with World Stem Cells. The 59-year-old believes the treatment she received at the Mexican clinic in 2013 saved her life.

“I’d taken cancer tests but nothing showed up,” she said. “If you would’ve seen me, you would’ve seen something was wrong. I was in a very bad condition. I just lay in bed with oxygen and my brother and my son had to help me do everything.

“I still have challenges — with the humidity it’s a struggle — but sometimes I feel almost normal. I still can’t walk far, but I can talk, I can wash my hair, I can do a bit of housework. It gave me a better quality of life; they extended my life.”

Ms Darrell started smoking in her early twenties.

“I was never a heavy smoker — a pack would last me a week — but my insides were very weak and COPD is a degenerative disease, it only gets worse,” she said. “I smoked for 18 years. I stopped on January 21, 2000, because I knew something was wrong. I bought patches, used them for two weeks and never smoked again.”

Doctors initially attributed her breathing problems to asthma. In 2005 she learnt she had chronic obstructive pulmonary disease.

She went to the United States for a second opinion because she felt she was “being overmedicated” by her doctor here. The pulmonologist switched prescriptions but warned that “nothing much more could be done”. She thought she would be bedridden for the rest of her life.

“In 2013 I lost both parents, nine months apart, and I had to take care of my special-needs brother,” she said. “Life was really bad. I couldn’t work, I couldn’t bathe, couldn’t even comb my hair. I could only lay in bed.

“My condition was getting worse and on September 5 I was hospitalised.”

Doctors told her both her lungs “were just about gone”. A transplant was the best option they gave her but there was a long waiting list.

Aside from that, the operation would cost “somewhere in the millions” and insurance would not cover this.

“Financially it was out,” Ms Darrell said. “I could literally feel myself dying.”

Her son, Chickaya Darrell, started surfing the internet “because he knew I didn’t have much time”.

“He was trying to look at natural cures for people,” Ms Darrell said. “When he noticed I wasn’t getting better he became desperate and started reading up on stem cells which, even today, are experimental.

I have a Mexican girlfriend and she said, ‘Why don’t you check out Central America? Hospitals and clinics there are rated as some of the best’.”

The search led to World Stem Cells in Cancun. The clinic asked for her medical records but made no promises. Ms Darrell said: “They told us I had to be eligible.

“Dr Mahesh Reddy at Dr [Ewart] Brown’s [Bermuda HealthCare Services] was so supportive. Because my condition was so bad, others said that if I went overseas there was a possibility I wouldn’t make it; they didn’t give me any hope.

“I talked it over with Dr Reddy and he supported me. I hope Government allows [stem cell treatment here] because it could save a lot of lives.”

Ms Darrell was thrilled when World Stem Cells told her she had been accepted for treatment. Her son held a benefit in her honour that allowed her to move her plans forward.

“I would like to thank all of the people who donated,” she said. “I thank them from the bottom of my heart. We raised $16,000, which covered the surgery but not the hotel and other expenses.

“Time wasn’t on my side. I would’ve been living on a machine while on a waiting list for a lung transplant I couldn’t afford. I really didn’t think I would make it.

“This was nowhere near as expensive. They gave us an appointment and decided I needed to get there right away.”

She flew to Mexico on October 13. A doctor there, Ernesto Gutierrez, had scheduled her for five days of stem cell treatments starting on October 21. Still, there was a big question mark over whether she would be able to reach her destination. Ms Darrell said: “The doctor was concerned about me flying out as I was on oxygen 24/7 and airlines don’t provide oxygen.

“I prayed about it; I’m a very spiritual person. That’s when the miracles began. I got on the plane and never needed it.

“We had to spend the night in Memphis. I went almost 48 hours without it. My son was so worried but, even in Mexico, once the oxygen was there, I didn’t use it. I was very weak, I couldn’t walk, but I didn’t need it.”

The transplant took place on October 23.

“They took the bone marrow from my hips,” Ms Darrell said. “They said they got 860,000 good cells out of me, which surprised [Dr Gutierrez] because my condition had deteriorated.

“They did the transplant and I woke up that night and just got up and used the bathroom. I couldn’t walk before. From that day on, I’ve never had oxygen since.”

Her advice to the public is twofold.

“Anyone who is smoking needs to stop,” she said. “After what I’ve been through, if it could save someone’s life, maybe it’s my calling to at least let people know [COPD] doesn’t have to be the way it is. I’m the example. To have this disease, it’s a struggle. People who see me today say I don’t look like anything is wrong.

“I tried to talk to a few people [who I thought might benefit from similar treatment] but people are frightened. It was painful. If you have lung disease, they can’t put you out. They numbed me as much as they could but I felt every bit of the extraction.

“I would do it again. I had the will to live. My son is my only child. I needed to be here for him and I had a four-year-old grandchild. I needed to be around to see her grow up.”

• For more information, visit worldstemcells.com