A man in his 50s has died following complications related to a heart transplant. The man was one of two patients who, at the end of summer, were affected by a serious medication mix-up during surgery at Karolinska University Hospital.

On August 18, the two patients in the thoracic department were given the wrong medication. Instead of potassium chloride, which is used to temporarily stop the heart during surgery, they were given calcium chloride.

The surgeries were described as routine, but the error was discovered after one patient’s heart could not be restarted following the procedure. This information was provided by Eva Sundman Olofsson, head of intensive care and thoracic surgery at Karolinska, to Dagens Nyheter.

Both patients subsequently required ongoing care with the assistance of a heart-lung machine in an intensive care unit. They later underwent heart transplants in Lund.

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Now, one of the patients, a man in his 50s, has died. He reportedly passed away due to complications that arose after the heart transplant.

Karolinska University Hospital declined to comment on the death, citing patient confidentiality. The hospital’s own investigation into the medication mix-up is still ongoing.

The Swedish Accident Investigation Authority has also reviewed the incident. The agency launched its own investigation in September.

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