Haematology

Fellowship Winner Sets His Sights On Stroke

Reducing Health Risks Linked To Obesity

Research To Prevent Renal Transplant Rejection

Focus on Falls

Raynaud's Disease

Fellowship Winner Sets His Sights On Stroke
First Published: Investigator - July 2008
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A Flinders Medical Centre consultant neurologist is spearheading a campaign to increase the efficiency of stroke diagnosis and treatment by emergency medical services.

Dr Andrew Lee will use a two year NICS Fellowship awarded by the National Health and Medical Research Council to improve formal stroke education among emergency department staff and paramedics.

‘If clot busting drugs can be given within three hours of the onset of stroke symptoms, the number of people dying or becoming disabled after suffering an ischaemic stroke (stroke caused by blood clots) can be reduced.’

‘But to achieve this we need ambulance paramedics trained in stroke treatment and the seamless transfer of these patients to stroke units.’

Andrew said formal stroke education for emergency department staff and paramedics was lacking in Australia.

‘The NICS Fellowship will allow me to develop and deliver this knowledge for ambulance paramedics. I’ll also implement standardised systems to assess stroke severity and provide pre-hospital notification of incoming stroke patients.’

Andrew said best practice therapy for patients who had experienced stroke within the previous three hours was to be administered clot-busting agents.

‘I want to translate that therapy - that has been proven from 10 years research – and implement it into normal clinical practice.

‘It’s not always easy to identify a stroke patient, because stroke can masquerade as many other conditions. That’s what I hope to change with education and systems, so that paramedics and emergency department staff can quickly and effectively recognise and treat stroke patients.’

Andrew said if stroke patients were treated with the appropriate therapy in the shortest time there was a 30 percent increased chance that they would recover without disabling side effects.

Reducing Health Risks Linked To Obesity
First Published: Investigator - July 2006
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Reducing the risk of heart attacks and other obesity related illnesses is of prime concern for a group of researchers at Flinders Medical Centre.

Prof Campbell Thompson and Dr Arduino Mangoni are attempting to understand the changes that take place within blood vessels during and after the weight loss that is associated with gastric banding surgery.

Gastric banding is a non-invasive surgery where an inflatable silicone band is implanted into the patient’s abdomen and fastened around the upper stomach. This limits the amount of food the patient can eat and creates a sense of fullness earlier, thereby encouraging weight loss.

Investigators have found that when weight is lost other health issues such as diabetes, high blood pressure, sleep apnoea and the risk of heart attack or disease is reduced. It is believed that this is linked to the reduction of “bad” visceral fat within the body which sits around the abdomen and intestinal areas and appears to be the main cause of other weight related health problems. Subcutaneous fat, which sits around the thighs and buttocks, is considered harmless.

Rapid weight loss on the other hand seems to cause harmful compounds, also known as fatty acids, to be released from the visceral fat into the circulation. The Flinders team are focusing on the effects that these compounds have on blood vessels. Fatty acids appear to cause blood vessels to become stiffer and lose their ability to modulate the flow of blood and oxygen through the body at an optimal level. This can potentially lead to many health problems such as high blood pressure and an increased risk of heart attacks.

The study aims at producing important information that will contribute to the treatment of obesity, particularly gastric banding surgery.

Currently within Australia over two thirds of adults and one third of children fall within the overweight/obese body mass index (BMI) brackets. BMI is a calculation of height in relation to weight to determine whether the subject is in a suitable weight zone for their height.

Those with a BMI of over 30 with another complication such as diabetes or anyone with a BMI of over 35 are eligible for gastric banding surgery.

“As obesity continues to rise worldwide, this information is of critical importance to create awareness and promote healthier lifestyles for those with an inclination to obesity,” says Professor Thompson.

Research To Prevent Renal Transplant Rejection
First Published: Investigator - April 2005
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Advanced renal failure carries a very high risk of death from heart attack and stroke.

Amongst other abnormalities in blood chemicals and hormones, patients with renal failure often have a hardening of their arterial vessels which, in turn, increase the blood pressure causing further damage to the kidneys.

The Flinders Medical Centre Foundation has provided funding to Flinders Department of Clinical Pharmacology for a pilot study aimed to investigate the effects of renal transplantation on the stiffening of the arterial vessels.

Renal transplant patients will be studied before and after the transplant operation to see if they show minimal change or significant improvement in their vascular outcome.

Through this study Drs Arduino Mangoni and Jeff Barbara hope to be able to identify vascular changes if any, just after transplant and therefore be in a better position to identify those at risk.

‘Unfortunately some renal transplant patients have some degree of early vascular disease with a high risk of rejection later on. If we can pick them up at an early stage, rejection may be prevented’, said Dr Mangoni.

“We will measure the stiffness of the vessels before and shortly after the operation with a simple, safe and non invasive test. This will assist us to better identify and characterize those patients showing minimal change or improvement in stiffness post-transplant. Some people do well, some people not so well. We want to see if different degrees of improvement of the transplant could be predicted for late rejection”

Dr Mangoni’s project will hopefully lead to a larger project to test the hypothesis that arterial stiffness is an independent predictor of renal transplant rejection.

Focus on Falls
First Published: Investigator - March 2005
Updated:

Syncope is a transient loss of consciousness (fainting) due to a lack of blood flow to the brain. One reason for this is linked to a condition called Carotid Sinus Syndrome (CSS) where the over activity of the carotid sinus can cause a pause in the heartbeat or low blood pressure leading to dizziness and blackouts.

Generally complete recovery from a syncope episode is made but the consequences can be quite serious.

The Syncope Clinic has recently been opened in conjunction with the Falls Clinic, at the Repatriation General Hospital.

Dr Zbigniew Gieroba from the Repat and Dr Arduino Mangoni from the Department of Clinical Pharmacology will commence a new study at Flinders and Repatriation Hospitals looking into a link between Carotid Sinus Syndrome and hardening of the blood vessels to the brain.

The carotid sinus is a dilated portion of one of the major arteries supplying blood to the head. The sinus nerve innervates carotid sinus with blood pressure monitoring receptors. The sinus nerve sends information into an area of the brain stem that controls blood pressure and heart rate.

“The poor understanding of the mechanisms responsible for carotid sinus syndrome doesn’t allow us to maintain satisfactory management in many patients”, said Dr Gieroba.

“This study will test our theory that patients with CSS have a hardening of the vessels that supply blood to the brain. A sudden stimulation (carotid sinus massage) of stiff vessels may provoke significant falls in blood pressure and with consequent reduction in blood flow to the brain, hence dizziness and blackouts”

It is necessary to perform carotid sinus massage in supine and 70 degree head–up tilt position. The study will involve a head-up tilt table test (pictured Figure 1). The Task Force Monitor is the first of its type in Australia and the Southern Hemisphere and allows doctors to non-invasively monitor beat-to-beat blood pressure, heart rate and cardiac output.

Dr Gieroba says “If our hypothesis is correct there is a potential to manage Carotid Sinus Syndrome with medication to reduce the hardening of the vessels, such as cholesterol and or blood pressure tablets”.

Raynaud's Disease
First Published: Investigator - July 2004
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Researchers at Flinders are hoping a drug used to treat mental illness could be a key to help control the symptoms of Raynauds Disease.

Professor Bill Blessing and Dr Stephen Hedger from the Departments of Medicine and Neurology are working on the theory that Olanzapine could help relieve the symptoms of Raynauds Disease - a painful and debilitating condition - and are working towards a clinical study to begin in 2005.

Dr Jack Walsh, from Vascular Surgery and Professor Peter Roberts-Thomson from Medicine, Immunology, Allergy and Arthritis will also contribute to the study.

Raynauds Disease is a condition in which some of the body’s blood vessels constrict, most commonly in the hands and toes, either apparently spontaneously or in response to cold or emotional stress. This severe constriction hinders blood flow and is distinguished by colour changes of the skin.

A typical episode of Raynauds Disease is the sudden onset of cold fingers, beginning in a single finger spreading to other digits and associated with white skin (white attack). This is followed by blue discolouration lasting 15 to 20 minutes then as the skin recovers it goes through a red phase. The whole process is very uncomfortable and painful.

There are two main forms of Raynauds Disease. The primary form is more common in women and displays a colour change in the hands. The secondary form is more severe.

Professor Blessing says the clinical study will mainly focus on patients with primary Raynauds Disease.

“Evidence based on careful physiological studies in animals suggests that Olanzapine, a drug already used to treat mental illness, interacts with brain neural pathways regulating the sympathetic nerves that control the blood vessels,” said Professor Blessing.

“Our research has shown that Olanzapine inhibits discharge of the sympathetic nerves, reversing the constriction of blood vessels and restoring the blood flow. We hope to begin a clinical study in 2005.”