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Palliative care updates |
March heralded the 13th Annual Symposium of the Sydney Institute of Palliative Medicine. This is an annual meeting for palliative care specialists from Sydney and New South Wales to meet and discuss what is emerging in the world of palliative care.
The research workshop discussed several interesting projects underway. Paul Glare discussed the diagnostic accuracy of PaP score, which is a means of estimating prognosis in the cancer population. The most positive predictors include the development of anorexia, dyspnoea, a low performance status, increase in white cell count, decrease in lymphocyte count and a clinician estimate. The tool was developed in Italy as an aid to clinical decision-making in patients with advanced disease (please contact me for full reference).
There was also discussion regarding the use of nebulised Frusemide for the relief of dyspnoea. Anecdotal evidence suggests that this is an efficacious method although there is no clear guide to the mechanism involved. However, a randomised control study to evaluate this with collaboration between Australian and UK partners is in development.
Dr JanMaree Davis (St George Hospital and Calvery Hospital, Sydney) gave a presentation regarding new drugs in palliative medicine. There has been more discussion about the mechanism of pain in bony metastases. This is thought to be from osteoclastic bone resorption as well as a central and peripheral nervous system sensitisation. There is also thought to be an inflammatory process via prostaglandins on the peripheral nerves. Treatment mainstays remain radiotherapy as well as biphosphonates, Cox 2 inhibitors, but consideration should also be given to classically neuropathic pain, and in resistant cases, calcitonin.
Incident pain, i.e. pain only with movement, is notoriously difficult to treat and will often result in the development of opioid toxicity in patients. Newer agents on the market include transmucosal Fentanyl (Actiq lozenges available on SAS Scheme). The transmucosal route of absorption means that the analgesic is absorbed quickly and, in theory, should be short acting hence reducing the risk of accumulation of the opioid.
There has also been some preliminary work on topical opioids, especially for use on pressure areas, which anecdotally have been found to be helpful. This is of interest as opioid receptors were previously thought to be only in the central nervous system and would therefore require presence in the peripheral nervous system in order to work at a local level. There has been some research from Stein (1995) suggesting that opioid receptors are synthesised in the dorsal route and migrate to the periphery, hence the effectiveness of topical opioids. However, doses have yet to be standardised.
There was some discussion re cannabinoids. Currently there is no Level 1 evidence to support the use of cannabinoids in pain management. There has been no further information from the NSW Government regarding cannabis trials for patients with refractory pain.
There was also discussion regarding aprepitant and its use for nausea and appetite stimulation. This is available for three days only via the SAS Scheme.
Olanzepine and nausea and vomiting
There has been some preliminary work regarding Olanzepine, which is an atypical neuroleptic. It has been found to be effective in some instances of refractory nausea and vomiting and the establishment of weight gain.
Levomepromazine
Levomepromazine is available via the SAS scheme. It resembles Chlorpromazine and has its use as a potent broad spectrum anti emetic and sedative. It is not a new drug to palliative care but is a new drug to Australia. It is most likely to be used for intractable nausea and vomiting in the inpatient setting.
Opioid rotation
Associate Professor Janet Hardy discussed the merits of opioid rotation whereby you have improved pain control and reduced toxicity by swapping from one opioid to another or by changing from one route to another, i.e. oral to parenteral route. This has been a contentious issue in palliative care and is carried out with a frequency of 10 to 80%, i.e. there is a wide variation in personal practice. There have been no randomised controlled trials confirming the benefits of opioid rotation, although there has been a large number of retrospective and prospective uncontrolled studies. In conclusion to her talk, Associate Professor Hardy felt that there was no evidence to support opioid rotation, even though it forms part of common practise.
In summary, there are many new innovations going on in palliative care. However, as ever, palliative care is dogged by the lack of hard evidence in the form of randomised control trials due to the inherent difficulties in studying the palliative care population.
If there are any questions about the above measures please do not hesitate to contact me.
Joanne Doran is the area medical director of palliative care for the Northern Rivers Area Health Service based at St Vincent’s Hospital.
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