Image copyright EPA Image caption Forensic staff examined the bodies of the victims after the bombing in August 2004
BBC East Midlands Tonighthas learned that two thirds of children and adults who received a new lung had died within five years of receiving their treatment.
Many had also suffered for years before the major operation to help them breathe more easily, but it failed to save them.
Eighty-seven people, including three girls aged just seven years old, died in the attack in Tavistock Square on 10 August 2004.
It was the biggest attack on the capital since World War II.
After the blasts, operating theatres at the city’s John Radcliffe Hospital were closed and intensive care staff hurriedly worked to deal with most of the victims who had been discharged.
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Every available hospital could not cope with the influx of victims, so doctors say they should have put the biggest effort into protecting the lives of those who had survived.
A thorough investigation by the Healthcare Commission into the bombings found that conditions were so bad that staff were delaying life-saving operations and diagnostics, and patients waiting for complex tests were left dying.
Hospital and government spokespeople say safety was never compromised and the HCC report revealed serious failings that had to be changed.
Image copyright Getty Images Image caption Many people suffered for years before the major operation
But many hospital staff have said patients could have survived if safety measures had been put in place.
Hospital trust leaders tell the BBC it is true that the way the hospital operates as it has always done for hundreds of years, means it can be slow to react to patients who need immediate attention.
They also stress that patients must be treated before they even arrive to the hospital.
However, there are measures that could be improved to make hospitals more prepared, such as having less patients arriving in the back of ambulances, moving around and appointments.
Hospital bosses are now being urged to work more closely with the NHS to co-ordinate teams to cope with people who need intensive care.
Patients are also likely to have to spend longer in hospital, and doctors have warned that overcrowding could cause problems down the line, adding that all patients in intensive care need 24-hour security.