The Wairarapa District Health Board has been faulted over the death of an elderly man who was given the wrong drug to treat a stroke.
The case is detailed in a report released on Tuesday by Health and Disability Commissioner Antony Hill.
The 82-year-old was admitted to Masterton Hospital in 2011 following the stroke and it was determined that drugs, or thrombolysis, was needed to break down blood clots in his brain.
An unnamed house surgeon consulted a hospital protocol that spelt out the kind of drug to use, but not which exact drug.
The surgeon phoned Wellington's Capital and Coast DHB for advice, as it had written the guideline, but a miscommunication meant that a drug for heart attacks, not stroke, was given to the patient.
The elderly man died of a brain haemorrhage within days.
Mr Hill says mistakes by the doctor had a tragic outcome, but the Wairarapa DHB was responsible for system failures including an inadequate protocol.
Wairarapa DHB chief executive Graham Dyer says it accepts full responsibility for errors that resulted in the death.
Mr Dyer agrees with the commissioner that vital details to assist local staff were not included and changes have been made.
"We'd adopted but not adapted the protocol. In a larger organisation which has seen more of this type of case, the protocol was probably explanatory enough. In a smaller DHB, as has occurred here, there wasn't enough understanding and while the questions were asked, probably not the right question."
The commissioner says following a review by Masterton Hospital, changes have been made throughout New Zealand to improve stroke care for patients.
"Protocols have been corrected and clarified at both hospitals. The learnings from the case have been circulated throughout New Zealand.
"So the response has been a good response, the changes have been effective and have been transmitted through New Zealand and that does significantly reduce the chances of this occurring again."