Bay of Plenty DHB told the Health and Disability Commissioner that the department was busy and at 150 per cent occupancy at 7pm that night.
About three hours after the man arrived, he was moved to a bed in the corridor and reviewed by a senior house officer.
He was assessed and treated for gastritis by the junior doctor who had been working in the department for six weeks.
"[The doctor] did not consider the possibility of the more serious vascular disorders. In this scenario, most ED doctors would consider doing a bedside ultrasound."
After about seven hours in the hospital, he was discharged at 10.47pm.
The man's pain worsened overnight and he was taken by ambulance to the emergency department the following morning in a serious condition.
He was then diagnosed with having reduced blood flow to his large intestine and a blockage to one of the main arteries that supply blood to the intestines.
Nothing could be done to treat the man and he died two days later.
A number of deficiencies in the man's care were identified including a four-hour delay in seeing a doctor after arriving at the ED and a five-hour delay in taking a complete set of vital signs for the man.
The report said there was also a lack of supervision of a junior doctor, as well as the man not being seen by a senior doctor, as well as the initial misdiagnosis.
Health and Disability Commissioner Anthony Hill acknowledged that the ED had been busy but he was critical that "the man was not assessed adequately and was discharged inappropriately".
"Opportunities were lost to identify and respond to his condition appropriately".
Hill considered that the errors that occurred indicated broader systems and resourcing issues at the DHB and found the DHB in breach of the Code.
Hill recommended that the DHB provide a written apology to the man's family, which it has done.
Hill also recommended that the DHB provide an update on the implementation of an Acute Abdominal Pathway document, conduct an audit of the past three months of ED wait times, and provide junior ED doctors with clinical documentation training.
In response to the report, Bay of Plenty District Health Board interim chief executive Simon Everitt said this was a "tragic case" for which the BOPDHB has "unreservedly apologised" to the family, both at the time three years ago, and again more recently.
"In the three years since the case, a number of measures have been implemented to help ensure this type of incident cannot happen again."
The measures included improving staffing levels in the Emergency Department, including an increased number of senior-level staff, which Everitt said meant more consultant level supervision for junior doctors.
"All junior ED doctors have also been provided with documentation training at the orientation stage, with an emphasis on improved communication.
"An admission proforma - which includes guidance on assessments and investigations on elderly patients who present with acute abdominal symptoms – has also been developed."
Everitt said in addition to this, ED waiting times relating to higher acuity patients like the one in this case have been, and are, regularly audited.
"Whilst we could not have changed the outcome for the patient in this case, we failed to provide him and his family with the appropriate end-of-life care he and they deserved. And for this we apologise once more."
