This tragic death in custody in 2017 of a 27 yo woman in Northern Territory highlights the thrombosis risks of using an intubation strategy with general anaesthesia as a form of chemical restraint for purposes of psychiatric aeromedical transfer.
Here is the coroners summary of the death
Over a decade ago when I was doing ketamine sedation research for psychiatric aeromedical retrieval , after a conference presentation of my work, a former ICU nurse from Alice Springs came up to me and thanked me for my research as she expressed regret at how whilst working at Alice Springs ICU she would have to regularly admit mental health patients to ICU for elective intubation and anaesthesia in ICU in preparation for aeromedical transfer to either Adelaide or Darwin for admission to psychiatric hospital there. These were usually calm cooperative persons, not acutely agitated. The intubation and anaesthesia were a regular form of chemical restraint for aeromedical transfer, required by the aeromedical service.
In the years since that ICU nurse spoke to me, I had thought that such a practice had been reduced at least if not eliminated as I was aware in my state of Queensland that ketamine sedation had lead to a significant reduction in intubation rates for psychiatric aeromedical retrieval. In communication with other colleagues in other states who had implemented similar ketamine protocols I was aware they had experienced similar reductions in intubation rates for this patient group. They have published their data and this has been cited previously on this blog.
So it was with some surprise reading the coroner report into Naomi Smith’s death in 2017 that I realised this regular practice of electively intubating mental health patients for psychiatric aeromedical transfer in Alice Springs ICU was still occurring. Was it the only way she could have been transferred to higher level psychiatric care? Would she still be alive today if intubation had not been performed? Why wasnt ketamine protocol trialled? I cant say with any certainty about these matters but the pathologist performing autopsy wrote this:
“Immobilisation, necessary for transfer to a secure facility for
psychiatric condition, in the form of induced coma may have been
a further contributing factor to the development of deep vein
thrombosis.“
Surviving Sedation is indeed not just only about losing airway and stopping breathing but now add the risk of thrombosis to that deadly calculus. It is true that ketamine sedation may pose as much a risk of immobilisation induced thrombosis as intubation and general anaesthesia but it is also true that waking someone up from ketamine infusion is easier and quicker than if they are intubated as well, and less risk in general. There is also the added evidence based benefit that ketamine provides an acute anti suicidal effect. The tragic learning point from this case is that with deep prolonged or recurrent sedation regardless of intubation or ketamine or whatever sedative is used, there is a thrombosis risk related to immobilisation, the very goal often of chemical restraint. Therefore it is our duty in providing sedation to minimise its use and reduce such risks of the sedation.