The Nelson Marlborough District Health Board has refused to answer questions about how they reviewed procedures carried out by a surgeon who appears to have botched multiple operations at Wairau Hospital.
Board chief executive Chris Fleming said he could not comment as investigations were continuing.
However, he said the board would be reviewing the outcomes of the Health and Disability Commissioner's investigation and the coroner's inquest to ensure any issues identified would be taken into consideration.
Zimbabwe-born doctor Michael Parry had been under police investigation in connection with the death of a patient at the hospital but a crown solicitor concluded criminal charges would not be laid.
Fleming would not tell the Marlborough Express if they conducted a review into Parry's operations and what the outcome of the review was.
Fleming would not comment if they changed the way they monitored surgeons or if they had altered the hours surgeons worked in the aftermath of revelations around Parry's work.
The Medical Council said Parry would be subject to extraordinary restrictions if he returned to work.
Parry would need to undergo a performance assessment and if he passed he would only be able to perform minor procedures under supervision.
The council's education committee chairman Professor John Nacey said it was an unusual but necessary step.
"It's a very important move to ensure public safety."
Parry stood down from his post at Wairau Hospital after the death of Jim Nicholls, 81, during surgery to repair a hernia and remove his gall bladder in May 2012.
Parry was on paid leave until he resigned in May last year.
Another patient, Rachel Riddell, 31, died of blood loss in January 2011 after Parry removed her gall bladder.
A coroner's inquiry into the two deaths was put on hold in December 2012 when police launched a criminal investigation into one of the deaths.
The deaths, along with surgeries Parry performed on Angie Webber, 28, a 37-year-old Upper Hutt woman, and another patient, also came under scrutiny during the police inquiry.
On Wednesday police announced that evidence they gathered did not reach the threshold for prosecution and no charges would be laid.
Nacey said the case was among the most serious the Medical Council had investigated.
"It's a very, very serious case.
"[There have been] serious complications that have lead to patient injury and there's no dispute about that.
"Council will certainly be putting severe limitations on his procedures if he wants to return to work."
If Parry was able to gain employment in New Zealand his practise under supervision would be limited to endoscopy, removal of skin lesions and closure of wounds.
Beyond that the only procedures he would be able to under take would be as an assistant surgeon.
The Medical Council would not issue Parry a "certificate of good standing" unless he underwent a performance assessment. That would hamper his chances of gaining employment overseas, Nacey said.
"If he wanted to work in another country they would write to the Medical Council and ask for a certificate of good standing . . . and they would need to know about . . . the business to do with what's going on at the moment."
Riddell's sister, Lynn Weir, said she was shocked to learn charges would not be laid.
The Nelson Marlborough District Health Board had a lot to answer for because it was "fully informed after each of those misadventures" but allowed Parry to keep operating, Weir said.
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