Power tools a risk to surgeons' hearing

By MARTIN JOHNSTON health reporter

Orthopaedic surgeons have been urged to wear earmuffs to protect their hearing from power tools almost as loud as chainsaws.

A trainee orthopaedic surgeon, Dr Hamish Love, measured the noise from surgical power instruments used to drill and cut human bone, "a very hard substance", at Tauranga Hospital last year.

He said that on hip and knee replacement operations the drill was about as loud as a motor-mower and the oscillating saw even louder at 100 to 110 decibels. "That's getting up towards chainsaw level."

Overall noise, measured at the surgeon, was within the workplace recommended limit of 110 decibels, he said, but transient peaks often exceeded the 140 decibels permitted. "This constitutes a noise hazard and carries a significant, but unquantified, risk for noise-induced hearing loss."

Earlier research had shown that up to half of health staff who had worked long-term in orthopaedic theatres had signs of early hearing loss. "No one has really looked before into how much noise we do experience."

Dr Love now wears earmuffs during the noisiest work with power instruments and urges other surgeons to do likewise. A nurse slips them on and off as needed.

"You can't wear them for the whole procedure because it would interfere with communication."

Andrew Norton, the human resources general manager of the Waitemata and Counties Manukau District Health Boards, said it sounded sensible to wear earmuffs if surgeons were at risk of hearing loss.

"We would look forward to reading his paper. I think we will be sitting down with our clinical directors of orthopaedics and looking at appropriate hazard minimisation.

"I don't know what the practicalities of earmuffs would be."

Dr Love, who will present his findings to the Orthopaedic Association conference in Rotorua today, said patients need not wear earmuffs as it was only the surgeon who was persistently close enough to the tools to be at risk.