Plain English Summary
Background and study aims
Low blood pressure is the most common complication for patients attending for routine outpatient haemodialysis treatments (filtering out waste products from the blood). Low blood pressure could be due to too low a blood volume, but could also be due to relaxation of the blood vessels. We wish to measure blood pressure during dialysis with a more sophisticated blood pressure machine that provides information about the stiffness of the major arteries to see whether there is relaxation of these arteries occurring before a fall in blood pressure.
Who can participate?
Patients with long-term kidney disease who are treated by regular outpatient haemodialysis in the Royal Free Hospital can participate in the study.
What does the study involve ?
When patients come for haemodialysis we will use a standard blood pressure cuff placed on the upper arm which is linked to a blood pressure machine and a computer that can measure pulse wave velocity. This equipment is currently used in routine clinical practice. The only difference compared to a standard blood pressure machine is that the blood pressure cuff inflates three times. As with standard practice, blood pressure will be measured before dialysis, at 20 minutes, then hourly. If you have not had a recent electrical recording of the heart (ECG) we will perform one.
What are the possible benefits and risks of participating?
There may be no immediate benefits to any patient. No additional blood tests are required, and the blood pressure test is non-invasive and does not cause pain and is performed whilst patients are having dialysis. Similarly if an ECG is recorded, this is painless and can be done during the dialysis treatment.
Where is the study run from?
The study is run from the UCL Centre for Nephrology at the Royal Free Hospital, UK.
When is study starting and how long is it expected to run for?
The study starts in January 2013 is expected to end in late 2014.
Who is funding the study?
The study is funded by the Royal Free Hospital, UK.
Who is the main contact?
Dr Andrew Davenport
protocol version 4
Study to determine whether changes in pulse wave velocity are associated with changes in blood pressure in haemodialysis patients
Do changes in major arterial compliance occur during haemodialysis and does this lead to low blood pressure during haemodialysis?
London Central Ethics Committee, 05/09/2012, ref: 12/LO/0976
Prospective cohort study
Primary study design
Secondary study design
Patient information sheet
See additional files
All participants have a blood pressure cuff placed around their non fistula arm. Blood pressure measurements are taken three times spaced three minutes apart, during which time pulse wave velocity measurements are taken.
Post-dialysis, medical records are reviewed to see if there is any relationship to the changes of blood pressure during dialysis.
Primary outcome measures
Blood pressure and pulse wave velocity are measured using a blood pressure cuff.
Blood pressure will be measured at the start of a dialysis session, then at 20 minutes, one hour and then hourly during the dialysis session. Changes in pulse wave velocity and heartbeat variation will be reviewed to determine whether these are related to changes in blood pressure during the dialysis session.
Secondary outcome measures
Derived variables from pulse wave velocity.
Overall trial start date
Overall trial end date
Participant inclusion criteria
1. Patients with chronic kidney disease treated by haemodialysis
2. Patients who are able to provide valid consent
3. Patients who can have their blood pressure measured using an arm blood pressure cuff
Target number of participants
More than 100
Participant exclusion criteria
1. Patients who do not fulfil the inclusion criteria
2. Patients who cannot provide valid informed consent
3. Patients who cannot have their blood pressure measured using an upper arm blood pressure cuff
4. Those with atrial fibrillation and other cardiac arrhythmias
Recruitment start date
Recruitment end date
Countries of recruitment
Trial participating centre
UCL Centre for Nephrology
Royal Free Hospital Pond St
Royal Free Hospital (UK)
Funding Body Type
Funding Body Subtype
Results and Publications
Publication and dissemination plan
Planned publication in a peer reviewed journal.
Intention to publish date
Participant level data
Not provided at time of registration
Results - basic reporting
2013 results in https://www.ncbi.nlm.nih.gov/pubmed/24011131
- ISRCTN12870218_PIS_09Aug12_V4.doc Uploaded 17/01/2017