We are a group of researchers planning a small study to investigate the function of platelets in patients about to undergo major surgery on their blood vessels.
We are seeking a patient or member of the public to give feedback on the design of our study, creation of patient-facing documents and dissemination of our findings. Ideally the person would have had major non-cardiac, arterial vascular surgery in the past, or is awaiting this type of surgery. Reimbursement is offered.
A brief summary of our study is outlined below:
An assessment of platelet function in patients undergoing major non-cardiac, arterial vascular surgery
Platelets are the cells that help blood clot. Under certain conditions, this process becomes abnormal and the clots formed by platelets block off important blood vessels resulting in strokes and heart attacks. This is more common in patients who are older and also have high blood pressure or diabetes. As a result many of these patients are prescribed anti-platelet medications, such as aspirin and clopidogrel.
Increasing numbers of patients who require major operations of the blood vessels (vascular surgery) are also taking anti-platelet medications. On the day of surgery, they may require an epidural for pain relief. An epidural is an injection in your back that blocks the nerves carrying pain from the vessels and organs that are being operated on. Advantages of an epidural include excellent pain relief, earlier mobilisation, less likelihood of developing blood clots and shorter hospital stay. It is generally a safe procedure but one very rare risk is bleeding into the injection site in the back, which can have potentially devastating complications such as paralysis or death. Fortunately it is very uncommon and thought to occur in 1 in every 150,000 cases. The risk is thought to be slightly higher in patients who are on anti-platelet medications. and therefore guidelines recommend stopping anti platelet medications for between 5 to 7 days before an epidural injection. However, this is not based on any high quality research. Stopping these medications, even for a brief period can result in patients experiencing strokes or heart attacks.
For patients in whom the risks of stopping anti-platelet medications prior to surgery is deemed to be too high, epidural analgesia is unfortunately not an option. The aim of our study is to better understand the true effects that anti-platelet medication have on platelets that are circulating in the blood. We will use novel methods of analysing platelet function to enable this. We will aim to recruit between 40 to 50 patients that are scheduled to undergoing major vascular surgery at the John Radcliffe Hospital, Oxford. As part of the study, all we require is two to three teaspoons of blood from patients who have agreed to take part. This would be done during routine pre-operative assessment clinic visits so as to minimise participant burden. There are no further interventions or drugs that will be given as part of the study and the remainder to the study data can be collected from routine healthcare records.
As part of the grant application, we will cost for the time taken to participate in meetings and review documents in accordance with NIHR guidance.
Our status is 'Ongoing'. We are currently in the process of preparing our grant application and the deadline for the application is 25th September 2020.
Radcliffe Department of Medicine, University of Oxford, Oxford, UK