Coroner Dr Bernadette Boss has urged the private hospital to consider having two doctors, rather than one, rostered on to deal with emergencies at peak surgery times, among other recommendations.

She expressed "great concern" that a doctor who was going to make an emergency call in line with hospital procedures decided not to after saying nursing staff told him it would have little effect, seeing as he would be the first responder to his own call.

Dr Boss' findings on the death of Theodora Zaal, 75, were published on Thursday. Mrs Zaal suffered a cardiac arrest at the hospital on August 7, 2015, hours after undergoing surgery on an ulcer on her left ankle and leg.

Dr Boss outlined three occasions after the surgery when Mrs Zaal's blood pressure was found to be at levels which, according to the hospital's own procedures, should have resulted in a Medical Emergency Team call.

On each occasion, staff did not make the call. The hospital defended these decisions in each instance.

It submitted to the coroner that despite the guidelines, staff could apply discretion and acted appropriately.

On the instance where Dr Robert Pearlman said he was told making the call would have little effect, the hospital said an appropriate number of staff would have made themselves available to respond had the call been made.

Dr Boss said while she could not conclude that the failures of hospital staff to make these calls contributed to Mrs Zaal's death, she was "concerned that a system expressly designed to highlight early warning signs in patients was overridden without good evidence of the reasons why".

She recommended that where discretion was exercised in order to not make a Medical Emergency Team call, the reasons should be formally recorded "to put beyond doubt that patient warning signs have not been overlooked or disregarded".

While the hospital told Dr Boss most private hospitals only had one resident medical officer on duty to deal with emergencies, she also recommended that Calvary John James Hospital consider having two rostered on during peak surgery times, when most other doctors would be in surgery.

Nursing staff did eventually make a Medical Emergency Team call on the day of Mrs Zaal's death, but not until she went into cardiac arrest in the intensive care unit.

Dr Marta Kot, who led resuscitation efforts, told the coronial investigation the nurse initially allocated to use the defibrillator "was not able to manage [it] confidently".

"When I ordered to stop chest compressions, I observed the defibrillator was not ready to be used yet, so I ordered immediately to recommence effective chest compressions ... until the defibrillator was ready to use."

Dr Kot said she had to contact the intensive care unit manager to take over operating the defibrillator.

In her statement to the coroner, Dr Kot said the nursing staff's unfamiliarity with the defibrillation equipment and life support techniques was probably the result of limited exposure and a lack of frequent training.

She also said some relevant information about the resuscitation efforts was not recorded.

The hospital was critical of a number of aspects of Dr Kot's evidence, and said she was the only person to recall any difficulty or delay in using the defibrillator.

Dr Boss said she was unable to conclude that any delay in using the defibrillator contributed to the death of Mrs Zaal, who had suffered from heart conditions.

The coroner said she was satisfied the hospital had already addressed the risk to public safety in terms of the defibrillation process, having implemented plans to have all staff trained in advanced life support techniques by the end of 2019. The hospital had also provided a supplementary training session for intensive care unit staff after Mrs Zaal's death.

Dr Boss also recommended the hospital train staff on the importance of accurate record-keeping, and that it audit its central cardiac monitoring systems and defibrillators.

A hospital spokesman said it was reviewing the coroner's recommendations.

"However, during the process that was undertaken in relation to the coroner coming to their decision, Calvary has provided significant evidence in relation to inconsistencies in other evidence provided and maintains its position that the criticisms levelled at some staff members are not supported," he said.

The spokesman said all but two staff had completed advanced life support training, and they would finish it by the end of the year.