Clinical Research student Jenni Williams’ studies reveal new information about a technique known as Remote Ischaemic Preconditioning (RIPC) which involves temporarily restricting blood flow to a limb immediately before surgery, and has been found to significantly reduce subsequent tissue damage.
Clinical research to improve surgery outcomes
“One of the major problems associated with recovering from surgery is the tissue damage to organs caused when blood flow, and therefore oxygen, is temporarily restricted,” says Jenni.
“During RIPC the brief restriction of oxygen prior to surgery activates the body, preparing it for more substantial trauma.”
Jenni’s research extends the findings of a recent clinical trial run by Paul Young at Wellington Hospital testing this intervention in high-risk cardiac surgery patients. To shed new light on the technique, Jenni is designing and conducting clinical trials on volunteers.
The trials involve inflating a blood-pressure cuff on the upper arm of a patient for five minutes, releasing it for five minutes and repeating the exercise two more times. Jenni then analyses cells from the volunteer’s blood samples taken before and after RIPC. The subsequent changes in blood cells are leading her to believe that the body’s immune response is key to understanding RIPC.
Jenni says two areas of research interest are the white blood cells called neutrophils, thought to be largely responsible for damaging organ tissue following surgery; and cytokines, the ‘hormones of the immune system’, which play a fundamental role in cell interaction.
“One consistent effect we’ve observed is that preconditioning seems to reduce the activation of neutrophils, and Jenni’s study is the first to show this reduction occurring very quickly after preconditioning—within the first four hours,” says Jenni’s primary supervisor Anne La Flamme, Associate Professor in Cell and Immunobiology research in Victoria’s School of Biological Sciences and leader of multiple sclerosis research at the Malaghan Institute of Medical Research.
Jenni is planning a further trial to discover whether a stronger response from the immune system occurs when RIPC is applied 24 hours before testing the blood.
“This may give the body even more time to respond, and be even better prepared for surgery,” she says.
Jenni says it’s exciting working in an area of medical research where so little is known, and she believes the technique could eventually be applied more widely.
“If we can improve outcomes for surgery patients with such a simple technique, then that would be incredible.”
Jenni’s research is also supervised by Professor Richard Beasley from the Medical Research Institute of New Zealand.
Jenni, who is one of Victoria’s first PhD candidates in Clinical Research, has raised over $30,000 to fund her clinical trials, through grants from the Wellington Medical Research Foundation and the New Zealand Heart Foundation.
Her research is also supported by a Victoria University PhD Scholarship and the Victoria University Joy McNicoll Postgraduate Research Award in Biomedical Science.
Victoria University of Wellington, New Zealand