An emergency doctor has told an inquest "cognitive bias" played a role when he incorrectly diagnosed an Aboriginal man with a drug-induced syndrome, rather than identifying the stomach ulcers that led to his death.
The coronial inquest is investigating the circumstances surrounding the death of Kamilaroi-Dunghutti man Ricky 'Dougie' Hampson Jr after he presented to Dubbo hospital on August 14, 2021, feeling a popping sensation in his stomach and writhing in pain registered as "ten out of ten".
The 36-year-old died of perforated duodenal ulcers on August 16 at a friend's place, less than 24 hours after being discharged from hospital with over-the-counter painkillers. A witness observed he was in "obvious distress" when leaving.
Deputy State Coroner Erin Kennedy is being asked during the inquest to examine the factors that led to Mr Hampson Jr's death, including if racial bias played a role in his misdiagnosis.
He was diagnosed with cannabinoid hyperemesis syndrome (CHS), often seen in long-term cannabis users, and which displays symptoms such as nausea, vomiting and abdominal pain.
The court heard CHS was not uncommon at Dubbo hospital, with many of the patients diagnosed with the drug-induced syndrome identifying as Aboriginal.
The senior doctor, who cannot be named, admitted he incorrectly diagnosed Mr Hampson Jr with CHS, telling the court he first considered the diagnosis after the patient was brought to a bed in a wheelchair.
"It was the impression: the agitation, the writhing in pain," the doctor said.
The doctor said signs initially supported the CHS diagnosis. Mr Hampson Jr had told the doctor he had smoked a small amount of cannabis that morning, and his blood tests showed exhausted electrolyte levels, which could occur through vomiting.
The inquest has heard evidence that Mr Hampson Jr did not report either vomiting or nausea. He was treated with the droperidol - an intravenous drug used to reduce vomiting and nausea - along with morphine.
"It was the wrong diagnosis," the doctor said.
He said the diagnosis, along with no scans being ordered for Mr Hampson Jr, was a mistake, and a "matter of deep regret".
The doctor told the inquest his decisions were the result of "cognitive bias," explaining he had treated other patients with the same symptoms. As a result, he had mistakenly closed his mind off to other potential diagnoses.
"I accept that decision, it wasn't ideal," the doctor said.
Counsel assisting the coroner, Simeon Beckett SC, asked the doctor: "In that particular decision, [do] you accept there was cognitive bias?"
"Yes," he replied.
Asked if Mr Hampson Jr should have been referred for more abdomen scans, the doctor told the inquest: "In retrospect, absolutely."
The doctor said whilst he had treated Indigenous people for CHS at Dubbo previously, he denied the diagnosis for Mr Hampson Jr had anything to do with race.
"It was just the brain recognising the pattern when the patient came in," he told the inquest.
He was also adamant he wasn't made aware of any "popping" sensation in Mr Hampson Jr's stomach, arguing this would have been a red flag that resulted in a different treatment plan.
"One thing emergency physicians are scared of is someone saying they've got a popping feeling," the doctor said. "I would have remembered that information."
Earlier on Tuesday, the court heard from Dr Lisa Hu, a resident at the hospital who also examined Mr Hampson Jr. She said the senior doctor had diagnosed him with CHS, and noted it was not something she had seen much of before going to Dubbo.
"I would have only heard of it in passing…I have never really thought about it in a diagnosis," she said.
The use of droperidol on Mr Hampson Jr was also not recorded, with Dr Hu accepting this was unusual and not normal practice at the time.
Asked if she would change anything, the doctor told the inquest she wished she had been more "assertive" and "suggested some investigations".
The inquest continues.
13YARN 13 92 76
Aboriginal Counselling Services 0410 539 905
