New Zealand / Health

Woman overdosed after nurse gave five times more fentanyl in error

16:21 pm on 27 February 2023

By Hannah Martin of

A woman was supposed to receive 20mcg of fentanyl, but was instead given 100mcg accidentally, a newly released report from the health watchdog states. Photo: 123rf

A dialysis patient was accidentally given an overdose of potent opioid fentanyl, after a nurse mixed it up with an anti-nausea medication.

Deputy Health and Disability Commissioner Dr Vanessa Caldwell found a registered nurse and Te Whatu Ora Counties Manukau in breach of the patients' rights code over its care of the woman aged in her 50s, who had routine dialysis at Middlemore Hospital for end-stage chronic kidney disease.

In October 2019, she was being cared for by nurse B, who gave her pain relief and anti-nausea medication before dialysis. Mrs A took controlled drug fentanyl and OxyNorm10 for ongoing chronic pain relief.

Counties Manukau's policy required controlled drugs to be checked by a second nurse prior to administration.

After Mrs A's medication was removed from the dispensing machine and checked by a second nurse (nurse C), the medication was taken to her ward and put aside.

Nurse C was busy with other patients, so nurse B decided to give the anti-nausea medication (ondansetron) first, before asking for nurse C's help.

Te Whatu Ora Counties Manukau (formerly the DHB) was told to provide a written apology to the woman, and had subsequently made a number of changes following the incident. Photo: RNZ / Marika Khabazi

About 7:35am, nurse B picked up the fentanyl ampoule from the dish, thinking it was ondansetron and drew up the entire amount - 100mcg​ - into a syringe, and administered it.

The correct dose of fentanyl would have been 10-20mcg​, the report stated.

It was not checked by another registered nurse, as nurse B believed he was giving ondansetron.

Nurse B realised the error and "immediately" reported the fentanyl overdose, before informing and apologising to Mrs A.

About 7.40am, Mrs A reported feeling dizzy and sleepy.

Renal registrar, Dr D's clinical notes state Mrs A "accidentally got 100mcg fentanyl instead of [20].... vague and appears drowsy".

She was given naloxone (used to rapidly reverse opioid overdose), resulting in a "cold-turkey" withdrawal.

Mrs A told HDC she was in "severe pain all over my body, screaming and throwing my body all over the bed ... I had gone into severe withdrawal symptoms".

"The pain in my body was off the wall. I just thrashed around while nurses tried to hold me down."

After the event, she was transferred to the emergency department for monitoring and discharged later that day.

Caldwell found nurse B in breach for multiple issues, including failing to prepare the fentanyl immediately, incorrectly administering fentanyl, not monitoring her respiratory rate and providing insufficient documentation.

"Fentanyl is a strong opioid that requires careful preparation and administration owing to its potency," Caldwell said.

"The [nurse] had a duty of care to the patient to prepare the fentanyl safely."

Caldwell also found Counties Manukau in breach, due to the practice of nursing staff on the dialysis unit inappropriately removing medication from the dispensing machine before it was required.

Multiple staff did not adequately document Mrs A's care and observations, and her pain was not assessed using an objective pain assessment tool, Caldwell noted.

She recommended the nurse and Counties Manukau provide written apologies to Mrs A.

The health board was advised to undertake a compliance audit of opioid and controlled drug policies, and provide training to ensure clinical staff are aware of the naloxone policy.

Since the complaint, Te Whatu Ora has mandated staff no longer remove medication from the dispenser before patients are physically in the unit, and medication is to be checked out as close to administration time as is practically possible, the report stated.

The nurse also made changes to his practice to ensure "that it is safe, competent, [and] professional", Caldwell said.

This story was originally published on Stuff.