Anaesthetist’s evidence at inquest

Press, 9 March 1988, Page 4

Anaesthetist’s evidence at inquest

Some aspects of an operation during .which a Rangipra woman suffered a caijciiac arrest and later ■ died {were "in hindsight" i not good practice, admitted the) anaesthetist, John Xavier j Louw, [in the Coroner's Court yesterday. Mr Louw also admitted in cross-examination that he held no post-graduate qualifications in anaesthesia. Mr! I Louw, who had earlierj gone to the High Couri! in an unsuccessful bid not to have to give evidence that might dis-> credit or incriminate him, entered the witness-box yesterday at the! inquest into lithe death of Nancy Ruth)| Hendrie, aged 53. Mrs i Hendrie had suffered' a cardiac arrest and hypoxia (lack of oxygen) during j minor surgery on the elbow and wrist of the right! arm on July 9 last. She )did not regain consciousness and died four days]' later in the Christchurch] Hospital intensivecare |i unit. Mr] Louw yesterday detailed the anaesthetic procedures and disclosed a

possible problem with the “endotracheal tube” inserted into the patient’s windpipe to administer anaesthetic gases. The tube is held in place by a little inflatable cuff which seals against the sides of the windpipe. Mr Louw said that he was at the time satisfied that it was not over-inflated. He was then not aware of anything which could inflate it further, “but I am now,” he said. He j became aware, through an article he received in August, that nitrous oxide could diffuse into the cuff, overinflating it. That was a possibility during Mrs Hendrie’s operation, said Mr Louw. Mr Louw told the Court that Mrs Hendrie had no previous history of {illness or allergy, and appeared normal in a pre-operative examination. About 9 a.m. she was anaesthetised with thiopentone, atropine and a muscle relaxant, suxamethonium, then maintained on oxygen, nitrous oxide and 0.5 per cent to

1 per cent halothane.

An excess pressure alarm on an automatic ventilator was triggered. Mr Louw said that he interpreted that as being caused by the patient’s "breathing against the machine,” and reset the alarm to a higher value. He told of diagnosing a cardiac arrest at) 9.40 a.m., when Mrs Hendrie had no pulse, and the drape was removed from her face to show cyanosis (blue-grey colour) and dilated pupils. Cross-examined by Mr Tim Gresson, for the Crown, Mr Louw said that the operation! could have been done with a- local anaesthetic but he wanted to make it jas easy as possible for the surgeon.

He said that he I made detailed checks on the anaesthetic machine and all was normal. There were no problems with inserting the endotracheal tube, although it was found to be too far in and was repositioned before being tied in! place.; {

Mrs Hendrie was’ being manually ventilated, but

Mr Louw did not recall noticing any difficulty or resistance in inflating her lungs. A short time after being put on an automatic ventilator, a “paw” alarm, indicating excess pressure, sounded. Mr Louw said he interpreted that as Mrs Hendrie, recovering from the effect of the relaxant, suxamethonium, beginning to breath spontaneously and | breathing "against the machine.”

The automatic ventilator had been brought into use because the patient had not recovered from the usually short-acting drug, he said. The normal setting for the alarm was a pressure of about 20cm to 30cm of water, and he turned it up to “about 50, possibly higher,” said Mr Louw. It was abnormally high, he admitted |in further questioning by Mr Gresson.

The automatic ventilator was switched off, to see whether Mrs Hendrie was able to breath spontaneously but the rebreathing bag (a rubber

bag like a football bladder) was not moving “adequately or frequently enough,” said Mr Louw.

The machine was switched on again, and Mr Louw checked the gauges on the anaesthetic machine and checked Mrs Hendrie’s pulse on a monitor.

Cross-examined as to the “distinct possibility” of an airway obstruction, Mr Louw said that that was not in his mind at the time. He was “not sore” about Mr Gresson’s suggestion that it would have been better to turn off the anaesthetic gases and try to ascertain what the problem was with her breathing., “I thought I had an adequate explanation. I thought the patient had started to breathe,” he said. l !

The operation began about 9.10 a.m. and from then until 9.30 a.m. Mrs Hendrie had to be manually or machine ventilated "most of the time,” he said.

He had not mentioned the breathing difficulties

to the surgeon until 9.40 a.m. when the drapes were removed from .Mrs Hendrie’s face for { the first time, all gases except oxygen were turned I off, and resuscitation began. The Court heard {that there was no blood-pres-sure monitoring, because the right arm was toeing operated on and the] left arm carried a pulse monitor which would have been interfered with ; had a pressure monitor been added.

Mr Louw agreed that a pressure cuff could have gone on an ankle, "but I didn’t realise the operation was going wronk to that extent.” He agreed that, in hindsight, it was not good practice to have left {Mrs Hendrie’s side, albeit; for "a minute at most,” to get a music tape fromi his locker. Nor, he agreed, was it good practice to have left her face draped for so long when she i had had breathing trouble virtually from the start of anaesthesia. “I wasn’t aware :how bad her ; condition was.

But in hindsight, no,” he said.

Cross-examined by Mr Brian McClelland, Q.C, counsel for the Hendrie family, Mr Louw said that he held no post-graduate qualifications in anaesthesia. Asked whether there were any qualified anaesthetists at Ashburton Hospital, he said there were from the point of view of experience but not in terms of formal qualifications. Mr McClelland also took issue with Mr Louw’s brief of evidence, which said that Mrs Hendrie was maintained on 0.5 per cent to 1 per cent of the anaesthetic . gas, halothane, when the anaesthetic report said that she was started off at 2 per cent.

The dosage was vital to the inquiry, said Mr McClelland.

Mr Louw agreed that Mrs Hendrie was originally going to have only a local anaesthetic but denied knowing that she had had difficulty previously with a general anaesthetic.