According to an inquest heard, a patient was given a lethal overdose of insulin by a tired junior doctor, after working more than 100 hours in a week.
Dr Helen Pike, 30, gave the injection herself, in spite of 2 nurses warning her. The patient, Tony Wright, 58 suffered a massive cardiac arrest just a few minutes later. 10 days later, he passed away in the hospital's ICU.
Once his wife heard about the gruelling work schedule of Dr.Pike, she did not hold Dr.Pike responsible for what happened.
During the hearing at Leeds Coroners' Court, Freda Wright, 71, told the hospital doctor: "I would just like to say that we do not attach any blame to you. You did your best."
The tragedy shows how inadequate rest and long work hours affect junior doctors while taking life and death decisions.
Michael Summers of the Patients' Association said: "Junior doctors work very, very long hours. With such a high bed-occupancy in hospitals, doctors are working extremely hard and on occasions longer hours than is acceptable, the problem is mistakes will be made as a result of those pressures.
"The rules are there but they are not necessarily being adhered to."
The tragedy happened in December 2003. Dr Pike was supposed to have been working six 13-hour shifts, but as a result of working extra hours and exchanging shifts with colleagues she worked for more than 100 hours in seven days during that time.
Most of the short naps were in the hospital staff room and usually interrupted by calls for her to return to the wards.
Dr Pike was a senior house officer at Leeds General Infirmary during that time. According to her police statement, she had been worried about the worsening of Mr Wright's condition after an artery bypass operation and she had tried to get him admitted to a high dependency unit.
The amount of potassium in his blood had increased to fatal levels and it were decided to give him insulin to bring them back to safe limits. Usually, 5-10ml was injected, but that day, Dr.Pike injected 50ml into his foot and he suffered a heart attack 10 minutes later.
The inquest was told, that 2 nurses Angeline Tie and Amanda Dana-Brandt had realised that the dosage was 10 times higher than usual amount and questioned Dr Pike, who took the syringe and administered it herself.
Miss Dana-Brandt said: "Angeline decided she was not going to give the injection and I would not have given it myself without confirming the dosage was correct. I said to her 'are you sure this is correct?' Dr Pike then took the syringe from Angeline and set off toward's Mr Wright's bed."
Miss Tie said the doctor was in a rush. "I followed her and stopped her along the ward. I wanted her to check what was in the syringe. I wanted to make sure she knew how much insulin was in there."
After a police inquiry, the decision was made not to press criminal charges on her. James Hopkins, the West Yorkshire police detective who looked into the case, was sympathetic towards the hard-working doctor.
He said: "We discussed the number of hours she worked that week and, to be honest, I empathise with her. I know what it's like to average about four hours sleep and work for days.
"At no time was there any attempt to cover up the fact that the doctor had prescribed this medicine and at no time did she try to place the blame on any member of staff. It was a full and frank admission with the mitigation of the hours she had worked."
Mr. Wright, from Leeds, had respiratory problems, kidney disease and furred arteries.
The impact of insulin injectionon Mr. Wright's death was confirmed by Pathologist Professor Alexander Forrest.
Commenting on the cause of death, he said: "It was not necessarily the primary cause but would Mr Wright have had a cardiac arrest at that time had the injection not been given? The level of probability is probably not. It is possible if he had not had a cardiac arrest he would have survived."
A narrative verdict in which Assistant Deputy Coroner Mary Burke gave the cause of death as brain damage due to cardiac arrest caused by complications of surgery, an insulin overdose and chronic obstructive airways disease was recorded.
After the hearing Mrs Wright, who has received £11,000 in an out-of-court settlement with the hospital trust, said: "It was a fair hearing. They have admitted that a mistake had been made and I accept that."
Less than a year after Mr. Wright's death, law under the European Working Time Directive restricted junior doctors hours, limiting them to a maximum 58 hours a week with set rest periods.
Dr Pike still works as a registrar at the hospital but was unavailable for comment yesterday.
A spokesman for the Leeds Teaching Hospitals NHS Trust said at the time Dr Pike was contracted to do a maximum 72 hours a week. "Although we carried out a full internal investigation following Mr Wright's death, we will study the coroner's findings thoroughly to see if any further action is required."
According to a BMA spokesman, junior doctors still work very long shifts and the rooms used by staff to take rest have been closed as per the new rules.
"It is common for junior doctors to work at full intensity for up to 13 hours, which can have an effect on their performance and decision-making."