A man who died following a lung operation was found to have had a lethal level of anaesthetic in his bloodstream, a forensic pathologist told an inquest on Friday.
Ricky Ho Kam-chuen, 64, died at Hong Kong Baptist Hospital in Kowloon Tong in 2013 following a pleurodesis procedure performed by cardiac surgery specialist Anthony Yim Ping-chuen. Yim is best known for being the doctor of late Canto-pop lyricist James Wong.
The medical procedure required an injection of a mixture of lidocaine, an anaesthetic, and sterile talc powder, in order to spark irritation to close off the space between layers in the lungs to cure the pneumothorax Ho suffered from.
Forensic pathologist Poon Wai-ming testified on Friday that his autopsy found a lethal level of lidocaine in the deceased’s blood, leading him to conclude the “adverse effect” of the substance directly caused the man’s death.
He told the Coroner’s Court, which was trying to determine the cause of death, that the level of anaesthetic reached 11 micrograms per millilitre in the man’s blood, twice the maximum therapeutic level of five.
The known lethal level ranged from 10 to 25 micrograms per millilitre, he said, according to figures from the International Association of Forensic Toxicologists.
He believed that on March 27 in 2013, the day the procedure was performed, Ho was hit by an overdose followed by convulsion and lack of blood supply, and then coronary occlusion – or blocking of the coronary arteries.
He said his heart was “the other significant condition contributing to the death” of Ho, who suffered from heart disease to begin with, but it was not the main cause.
But he noted every individual reacted differently to the anaesthetic. “[Ho] had serious heart disease, so it could have been lethal,” he said.
Barrister Alfred Fung Kwok-chor, for Yim, quoted an expert and the manual of Queen Elizabeth Hospital, saying the lethal level should be above 25 micrograms per millilitre.
Poon responded by saying the figures he cited were only in reference to past cases, and that people could die following an intake of as little as 10 micrograms per millilitre, and it was not a clear-cut figure.
Fung also suggested Ho eventually died of heart occlusion, even if the drug was at play.
Poon hit back and invited the court to imagine a man being stabbed before losing a lot of blood and eventually succumbing to his own heart condition.
“His cause of death would still be that he was stabbed,” Poon said.
The inquest continues before coroner Ho Chun-yiu on September 27.
Article source: http://www.scmp.com/news/hong-kong/health-environment/article/2022100/hongkonger-who-died-after-lung-operation-had