The Waikato District Health Board has been found to have breached the rights of an ovarian cancer patient who was given the wrong dose of chemotherapy drugs.
The 51-year-old woman originally weighed 84kg when she began her chemotherapy treatment in 2012, which included the drug carboplatin.
The woman's weight fluctuated, and a year later she weighed 65.6kg.
A scan showed the cancer had spread and the woman agreed to try a single agent carboplatin treatment.
However, the oncologist calculated the woman's first dose of single agent carboplatin based on her original weight of 84kg, because her weight loss had not been noted in the DHB's computer based calculator, called the Aesculapius programme.
The woman received treatment based on her 2012 weight and at her next consultation the oncologist recorded that the effect of the carboplatin seemed to be favourable.
Further doses of 600mg carboplatin were administered.
Health and Disability Commissioner Anthony Hill found the DHB was in breach of the Code of Health and Disability Services Consumers' Rights with respect to the woman's treatment.
Her weight loss had been noted by her oncologist but never entered into the Aesculapius programme because the oncologist had been working remotely and did not record the information when they returned to the DHB.
A chemotherapy nurse noticed that the woman had been receiving chemotherapy based on a weight of 84kg, 20kg more than her then actual weight of 65kg.
Commissioner Hill's report found systemic issues at the DHB contributed to this error.
These included patient information only being able to be recorded in the chemotherapy treatment computer system at the DHB, where it was based, and not by oncologists working at off-site clinics.
There were insufficient safeguards to identify the use of historic data, and whether the weight and creatinine levels on the day of delivery differed from that data, he said.
The oncologists were unable to update patient details remotely, and the patient's weight was not displayed prominently or consistently in the clinical file, which meant it was not necessarily brought to the clinician's attention at clinic appointments.
Hill was critical of the oncologist for not ensuring that the calculations for treatment, which he signed off, were correct.
Hill recommended the DHB provide HDC with a detailed update on how clinicians' ability to access the Aesculapius programme remotely was affecting their service delivery, the results of the review of both DHBs' models of service, and an assessment of the effectiveness of the changes made to its service delivery following the review.
Hill also asked the other DHBs to report to HDC on the effectiveness of the changes it has made, including the new practise by chemotherapy staff of weighing patients prior to treatment, and notifying a clinician at the other DHB if a discrepancy is detected against the script.