Coroner probes how man died during root canal procedure

His dentist Gregory Tilley then administered a local anaesthetic and began the root canal procedure.

Dr Singh observed that Mr Anderson’s heart rate and oxygen levels had dropped and ordered Dr Tilley to stop the procedure, while he performed a jaw thrust to open Mr Anderson’s airway and begin resuscitation. Mr Anderson’s breathing was shallow and by 9.15am no pulse could be detected.

In his evidence to the inquest, expert witness anaesthetist and intensive care physician Forbes McGain said he was concerned no trace of a record of Mr Anderson’s blood pressure levels could be found, despite it being common for blood pressure to fall dangerously once Propofol took effect.

“What troubles me is that the anaesthetist was delivering Propofol without checking the blood pressure at any point that I can see,” he said.

“The source of truth in my case would be the anesthetic chart because that’s where anaesthetists would normally document blood pressure. Nowhere can I find any documentation of a blood pressure. I can’t see evidence that [Mr Anderson’s] blood pressure has ever been documented or measured anywhere.”

He said while he felt the resuscitation measures were appropriate in the circumstances, he was concerned by Dr Singh’s lack of “constant vigilance” around the use of Propofol.

“It’s an incredibly dangerous drug that needs to be very, very carefully [used] with great attention to detail,” he said.

Barrister Paul Halley, who is representing Dr Singh, told the inquest his client had used an automated blood pressure monitoring device, but had failed to document it on a medical chart.

The inquest heard a triple zero call was made about 9.17am with the Metropolitan Fire Brigade arriving first at 9.23am.

An automated external defibrillator was used to shock Mr Anderson’s heart, while Dr Singh administered two doses of adrenalin.

The court was told a “bag valve mask” – or manual resuscitator – was used by Dr Singh, but he made no further attempts to intubate Mr Anderson.

“I was surprised that he [Dr Singh] didn’t try for a second time … to intubate the patient,” Professor McGain said. “He was evidentially the most experienced person able to do that … he was more experienced than the ambulance officers.”

The court heard that paramedics arrived at the Collins Street building at 9.26am, but it took them eight minutes to get to the dentistry clinic located on the eighth level of the busy complex. They later said the room was crammed and it had been difficult to access Mr Anderson.

The inquest was told that while Mr Anderson, who was 180 centimetres tall and weighed 120 kilograms at the time of his death, could be considered overweight, he was young and otherwise healthy.

“He walked into a dental office, he received Propofol and then he was dead within an hour,” Professor McGain said.

“What happened? What is the reason for that? Well, the thing is he received Propofol, which causes respiratory depression and it also causes cardiac depression so both of those things have contributed and he has died.”

Professor McGain said while Propofol was an appropriate drug to be used for sedation during a root canal, in his medical opinion Mr Anderson’s weight was a risk factor for complications and meant an anaesthetist should monitor his breathing and heart rate more closely.

Forensic pathologist from the Victorian Institute of Forensic Medicine, Matthew Lynch, told the inquest his examination of Mr Anderson had found his heart was slightly enlarged and upon microscopic examination he found a narrowing of a blood vessel in the heart that may have increased his vulnerability to cardiac arrhythmia.

Dr Lynch said he could not say with any certainty what role, if any, these abnormalities played in his death.