Record of Investigation into Death (Without Inquest)
Coroners Act 1995
Coroners Rules 2006
I, Glenn Hay, Coroner, having investigated the death of
Michael Laurence DEAN
WITHOUT HOLDING AN INQUEST
Michael Laurence Dean (Mr Dean) died on or about the 25 May 2008 at his residence in Glenorchy.
Mr Dean was born in Hobart, Tasmania and was aged 38 years. He was single and in receipt of a disability pension at the date of his death.
I find that Mr Dean died as a result of multiple drug toxicity (moclobemide, venlaxafine, zopiclone, fluoxetine, oxazepam).
At the time of the Mr Deans death he was being treated by general practitioner Dr Susan McKenzie of the Lindisfarne Clinic and psychiatrist Dr Brian Ferry of the Hobart Clinic.
Circumstances Surrounding the Death : -
Mr Dean had served briefly in the Royal Australian Navy up until 2004 when he was discharged and diagnosed as suffering Post-Traumatic Stress Disorder (PTSD). I note in a report from Consultant Psychiatrist Dr John Cronin that Mr Dean had become an informant in relation to a sex scandal while stationed at HMAS Cresswell in July 2004 and as a result he had received recurrent threats on his life which caused him severe anxiety and depression. Dr Cronin felt this was best described as PTSD. Mr Dean was hospitalised for this condition several times including in 2007 at the time Dr Cronins report was compiled. Dr Cronin comments that Mr Dean "suffered recurrent, intrusive and distressing recollections of the death threats," and that it was difficult for him to go to his house "for fear of what he will find there." He was also noted to have "moderately severe sleep disturbance, periodic episodes of irritability and difficulty concentrating, is hypervigilant and has an exaggerated startle response."
Following his discharge from the Navy, Mr Dean had lived in Melbourne at the Richmond Fellowship where he received further threats on his life. I also note that in 2006 Mr Dean had worked briefly as a ticket inspector for Connex and was informed that he had been overpaid by some $11 000 which he was required to repay. An assessment report compiled by Consultant Psychiatrist Dr Les Ding comments that this situation caused him intense concern, and consequently he was admitted on several occasions to the Victoria Clinic in Melbourne for treatment.
In late 2007 or early 2008 Mr Dean returned to Tasmania, where he resided alone in a unit in Glenorchy which was also associated with the Richmond Fellowship. During this time Mr Dean was receiving ongoing medical treatment from Dr Susan McKenzie for his PTSD, depression and also for alcohol dependence. He was also receiving treatment from psychiatrist Dr Russell Pargiter, and then briefly by psychiatrist Dr Brian Ferry.
Mr Dean was regularly checked on by carers and was also by his parents who would see him several times a week. Mr Deans father, Mr Laurence Dean recalls his son visiting him at his home on Sunday 25 May 2008, to get some assistance to hang a picture he had obtained. Mr Dean left his parents home at around 5:30pm which was the last known time he was seen alive.
At around 5:00pm on Monday 26 May 2008, a support worker for the Richmond Fellowship, Mr Charles McIntyre (Mr McIntyre) commenced work. He was informed by other staff that Mr Dean had not been seen on their routine checks that day, although he considered that this was not unusual on account of Mr Deans known unusual sleeping habits. There had been no answer to knocks on his door or telephone calls to his home up until 5:45pm that evening.
By 9:15pm Mr McIntyre had not had contact with Mr Dean, and after consulting with his Manager, at 9:35pm he attended Mr Deans unit where he entered using a key held by the Richmond Fellowship. On entering the unit, Mr Deans body was located face down in a pool of blood in the dining area. He was apparently deceased. Emergency services were contacted which arrived a short time later and confirmed that Mr Dean was in fact deceased.
Attending police noted that a note had been placed on the door to Mr Deans unit which stated:
"Good morning staff! Just letting you know that I am having a bit of a sleep-in. I didnt get much sleep last night / early this morning so I am pretty exhausted. Cheers, Michael."
The writing was subsequently identified by his father as being Mr Deans writing. An investigation of the scene by police established that there were no suspicious circumstances.
A post-mortem examination was conducted by Forensic Pathologist Dr Donald Ritchey. Dr Ritchey concluded that the cause of Mr Deans death was multiple drug toxicity (moclobemide, venlafaxine, zopiclone, fluoxetine, oxazepam). In particular, toxicology testing revealed a level of moclobemide within the reported fatal range, a greater than therapeutic level of venlaxafine and therapeutic levels of the other drugs detected. Dr Ritchey considered that there were two possible mechanisms of death in this case. The first is central nervous system depression, followed by respiratory arrest leading to death, and the second is "development of the serotonin syndrome, a potentially fatal drug interaction caused by mixing drugs of different classes that independently increase CNS serotonin levels by different mechanisms. Specifically, moclobemide (a monoamine oxidase inhibitor used as an antidepressant) should never be taken in combination with venlafaxine or fluoxetine (selective serotonin reuptake inhibitors "SSRIs") because of the possibility of developing this potentially fatal drug reaction. Serotonin syndrome is a clinical diagnosis that cannot be diagnosed or excluded post-mortem."
It is to be noted that toxicology test results were negative in relation to the presence of alcohol in Mr Dean's blood.
It is clear from all of the evidence that if Mr Dean intended to commit suicide then the combination of drugs detected in his system would certainly have been sufficient to have achieved that result. However if Mr Dean did not intend to commit suicide then his death should properly be viewed as accidental in manner.
During the course of my investigation I adopted several concerns raised regarding the circumstances of Mr Dean's death as they relate to the medical treatment he had been receiving and unresolved issues in regard to the possibility of an accidental death. The concerns were:
Was the combined drug toxicity due to medical error?
Was the combined drug toxicity due to a lack of understanding by Mr Dean about the dangers of mixing these drugs?
Was sufficient education provided by Mr Deans psychiatrists (specifically Drs Pargiter and Ferry) about the dangers of mixing these particular medications?
Did sufficient communication occur between Dr Pargiter and Dr Ferry regarding Mr Deans medication regime?
Was it reasonable for Dr Ferry to take Mr Deans word that he was on no medication prior to initiating a medicine regimen in this clinical context (first visit with Dr Ferry by a patient with a complex psychiatric history, etc)?
Dr Pargiter states that Mr Dean had been taking fluoxetine when he first saw him, but that this was ceased on 7 May 2008. When he next saw Mr Dean on 16 May 2008 it was discovered that he had mistakenly ceased taking two other medications (sodium valproate and zoplicone). Consequently he was re-commenced on these medications, and also he was also started on the anti-depressant moclobemide. Dr Pargiter did not see Mr Dean after this, as Mr Dean cancelled his appointment with the intention of seeing psychiatrist Dr Brian Ferry instead. In respect of the absence of a clinical handover of Mr Deans care between himself and Dr Ferry, Dr Pargiter comments that Mr Dean made a unilateral decision to seek treatment elsewhere and I did not have the opportunity to hand over his care to a colleague. It is noted that the error by Mr Dean in ceasing two medications did not cause Dr Pargiter to think that Mr Dean lacked understanding about the medications he was on. In fact conversely, Dr Pargiter considered that "…with his lengthy illness and its treatment he was sophisticated with regards to medications…and able to comprehend the dangers of unsupervised mixing of medication."
Following his last visit with Dr Pargiter, Mr Dean told both general practitioner Dr Susan McKenzie and also Dr Ferry that he was not taking any medications. Certainly, given Mr Deans complex history it would have been understandable to have been sceptical and cautious about such a statement, but in the circumstances I am satisfied that Mr Dean would have been fully aware that on ceasing treatment with one practitioner and commencing with another he needed to fully disclose to the new practitioner all the medications that he was still taking, and to cease taking any medications which were no longer being prescribed.
Dr Ferry prescribed Mr Dean the anti-depressant venlafaxine and also oxazepam for treatment of his anxiety, insomnia and alcohol withdrawal. Dr Ferry states that he advised Mr Dean of the side effects of these medications, and comments that "venlafaxine and oxazepam are a safe combination when done at the appropriate dosages." It is significant that not only did Mr Dean inform Dr Ferry that he was not taking medications, but the referral letter provided to Dr Ferry from Dr McKenzie also stated that Mr Dean was not taking any other medications.
While there is sufficient toxicological evidence available to establish that fluoxetine and moclobemide should not be prescribed or taken together and there needs to be a sufficient 'wash-out' period between the discontinuation of one drug and the initiation of the other and that in this case the possibility arises there was insufficient time allowed between those events, this alone did not result in Mr Dean's death.
I am of the opinion that no medical error occurred in the prescribing of medications to Mr Dean by any medical practitioner. While I accept that Mr Dean had some familiarity and experience with many of the medications he had been prescribed, I find that it is probable that Mr Dean did not understand or appreciate the risks of mixing the particular medications of venlafaxine or fluoxetine with moclobemide. However, as no medical practitioner had prescribed moclobemide in conjunction with either fluoxetine of venlafaxine it was not unreasonable that no warning or information was given to Mr Dean about the dangers of using these particular drugs in combination. While the absence of a more formal handover of Mr Deans care from Dr Pargiter to Dr Ferry was not ideal, Dr Ferry acted reasonably on the basis of the advice of both Mr Dean and Dr McKenzie that Mr Dean was not taking any other medications at the relevant time.
I am satisfied that a thorough and detailed investigation has occurred into the death of Mr Dean and that there are no suspicious circumstances. I accept the opinion of Dr Ritchey and find that Mr Dean died as a result of multiple drug toxicity (moclobemide, venlaxafine, zopiclone, fluoxetine, oxazepam). On the evidence I am unable to determine which of the two mechanisms of Mr Deans death identified by Dr Ritchey, in fact occurred.
As Dr Ritchey reported: "This case highlights the difficulties of managing patients that consult multiple practitioners for complex medical problems as well as the dangers of mixing these two classes of medications". Bearing that in mind, I recommend that specialist clinicians and medical practitioners in general continue to use caution when prescribing medications to those with mental illness, especially when their psychiatric history is extensive yet that patient may state they are taking no or have not been prescribed with any such medications. This caution may include communicating with previous specialist clinicians or pharmacists regarding medications previously prescribed and also clearly educating patients about the dangers of combining certain medications. Like other classes of medications, many drugs used to treat psychiatric/psychological conditions are potentially very dangerous at high levels and as this case has shown, there is a potential for a life-threatening situation to occur when certain drugs are used in combination with others.
I am informed that in the UK there is a requirement for patients to register with a single general practice and the entire medical history of the patient is transferred if there is a change of location/practice. While this may well limit patient choice, it is a system that may have some merit and go some way to overcoming the problems identified in Mr Deans death.
Further and while I am conscious of privacy and other issues, some form of centralised register of prescribed medications available only to medical practitioners or pharmacists treating a patient, especially those with psychiatric/psychological disabilities, may assist in limiting the risks clearly evidenced in this unfortunate death. I am informed the Federal Government is actively considering the implementation of a national and centralised register, but it may be many years before it is achieved. In my view this should be attended to urgently.
Mr Dean had suffered depression and most likely PTSD following an unfortunate incident whilst in the Navy, where he had been the target of disturbing and repeated threats on his life. This had a clear and profound effect on his ability to function normally, and as a result he had regrettably turned to alcohol as a coping strategy alongside the professional assistance he had been receiving.
Notwithstanding Mr Deans well documented problems and apparent candidacy for suicide, I cannot be satisfied on the evidence that it was certainly Mr Deans intention to end his life. While I cannot exclude this possibility entirely, I find on the available evidence that it is more probable that Mr Deans death was the unintended consequence of ingesting several drugs which in combination were sufficient to cause his death.
I wish to conclude by conveying my sincere condolences to the family of Mr Dean.
DATED: Friday, 23 April 2010 at Hobart in the State of Tasmania.