A surgeon and the Nelson Marlborough District Health Board have been criticised over the death of an elderly man on the operating table in 2012.
Listen to Health Correspondent Karen Brown discuss the report
The public health watchdog has not named the surgeon, but Radio New Zealand understands he is Michael Parry.
In a report, Health and Disability Commissioner Anthony Hill said the surgeon carried out open surgery to remove the gallbladder, and repair a hernia, on an 80-year-old man with significant medical problems.
The surgeon thought this operation went well, but an artery was damaged, the patient lost blood and a second operation was needed urgently.
Damage to another vein occurred during this operation, and the man died of shock and major blood loss.
Listen to DHB chief Chris Flemingon Checkpoint
Mr Hill said the surgeon made serious errors and may face legal action.
He said the performance by others in the team was sub-optimal.
DHB chief executive Chris Fleming would not confirm the surgeon's name, but told Checkpoint the surgeon had agreed not to perform keyhole gallbladder surgery, and probably should not have been doing open surgery either.
He said it was unacceptable for a surgeon to leave a dying patient.
"I think that's completely unacceptable, the senior consultant that's the surgeon in charge in the case, should be staying until everything is sorted."