A verdict of medical misadventure has been returned at the inquest into the death of a woman, who was discharged from hospital on two separate occasions in the days prior to her death in October 2016.

Anne Marie O'Brien presented at Mayo University Hospital with acute back pain in September 2016.

She died a number of days later, as a result of a heart attack, following complications caused by pneumonia.

The inquest heard that the 48-year-old had a number of pre-existing conditions, including Chronic Pulmonary Obstructive Disease.

Last May, Pathologist Dr Tomas Németh told the court that it was his view that Ms O'Brien had very serious pneumonia in the days before she died.

Today, Ms O'Brien's daughter, Laura, outlined how her mother had initially complained of back pain on the night of Saturday 24 September.

The following day she was brought to hospital, where some medication was prescribed before she was discharged.

Her condition deteriorated and by the following Thursday, 29 September 2016, she was in so much pain that Laura O'Brien called an ambulance and her mother was brought back to hospital.

Laura O'Brien said the staff there seemed to be ignoring her mother, who she said was in "agonising pain" and that no assistance was forthcoming to help manage her condition.

She told Coroner Pat O'Connor that she felt staff at the hospital seemed to think it was "fine to abandon her".

Ms O'Brien was discharged from hospital again the following morning, despite there being no improvement in her condition.

In the days that followed, she continued to feel unwell and her breathing became laboured.

Laura O'Brien said she was extremely worried about her mother's condition and that she felt she had nobody to turn to, as a result of the manner in which she had been treated in hospital in the preceding days.

She told the inquest how her aunt had called an ambulance to assist her mother on the afternoon of 2 October but that she had died on arrival at Mayo University Hospital.

Laura O'Brien said the last few days of her mother's life would remain with her forever.

She said she was haunted by what had happened and would never have peace of mind again, as a result.

In her evidence, Ms O'Brien's sister, Margaret Whelan, told the Coroner's Court how she travelled to the hospital on 29 September to see her sister.

She outlined how she saw two doctors attend to Ms O'Brien when she was lying on a trolley.

Ms Whelan said the two medics proceeded to argue about her sister's condition.

She said she had concerns about her oxygen levels and implored the hospital staff to assist her. She said her protestations were ignored and her sister fell from the trolley in what she described as horrifying scenes.

She said the entire situation was appalling and she queried why she had been sent home in a medicab, when she was so clearly in need of assistance.

Ms Whelan said that her sister had been treated more like an animal than a human being in the hospital.

On the night she presented at the Emergency Department for a second time, Ms O'Brien was seen Dr Babatunde Ayeni, who requested a series of blood tests.

One of these showed a CRP (C-Reactive Protein) reading of 183, when the normal range is between 0 and 5.

This test is used to check for the possibility of inflammation in the body.

When questioned by the solicitor for the O'Brien family, Damien Tansey, Dr Ayeni agreed this was "off the wall".

The doctor said he had a number of concerns about the patient on the basis of what he had seen - her CRP reading, shortness of breath and low oxygen levels.

He said all these contributed to his view that Ms O'Brien needed to be admitted for further medical management.

He told Mr Tansey that he spoke to a colleague in the Emergency Department on separate occasions and informed him of his concerns.

He said he was disappointed that what he had recommended was not acted upon.

Dr Awais Kahn said when he assessed Ms O'Brien, her orthopedic pain was his main focus.

Mr Tansey said he had "blindly accepted" this, despite the fact that the patient had COPD, was short of breath and had CRP readings that were a clear indicator of inflammation.

He denied there had been a heated discussion with Dr Ayeni about whether the patient should be admitted to hospital.

Dr Omotunde Oludayo Sanni - a locum Registrar who was on duty that night - said he did not want Ms O'Brien to be discharged.

He said it was extraordinary that this happened a few hours later.

In his summary, Mr Tansey said the inquest related to an extraordinary series of events, with tragic consequences.

He said the HSE could have intervened to address the relatively straightforward medical challenges Ms O'Brien presented with.

Mr Tansey said the evidence heard at the inquest showed Mayo University Hospital had neglected or failed to take appropriate action to intervene.

After considering the evidence, the coroner returned a verdict of medical misadventure.

He said it was an extremely difficult case for all concerned, especially the family of Ms O'Brien.

The Coroner said it was important to stress that there was no finding of culpability or responsibility attached to his verdict.

He said he hoped Mayo University Hospital would learn lessons from the incident.

The Health Service Executive has made an unreserved apology to the family of Ms O'Brien, for the standard of care provided to her, admitting it was not appropriate.

Sasha Gayer, SC for the HSE, read a letter of apology to the Court at the conclusion of today's proceedings.