Poor documentation and communication are believed to have led to a 75-year old patient's death in Whangarei Hospital.
The man, who died in February 2010, had undergone a total knee replacement surgery only days before his death.
The Health and Disability Commissioner said medical staff failed to respond to the man's deteriorating condition following the operation.
The man, referred to as Mr A, first sought knee joint replacement in 2006. At that time the anaesthetists considered it was not safe for him to have surgery because of his severe heart disease.
The man, who suffered from a severe heart condition and other diseases including type 2 diabetes.