None listed
Conditions
Brief summary
Patients with kidney failure on haemodialysis machines depend on a well-functioning surgically-created enlarged blood vessel in their arm, known as an arterio-venous fistula (AVF). These AVF can develop narrowings, which may progress to complete closure and failure, creating a surgical emergency. Every dialysis, the patient and their nurse check that the fistula is well-functioning by simple physical examination: i.e. can they feel a strong vibration and pulse; can they hear a loud noise with a stethoscope? If concerned, then a patient is referred for a formal Doppler study appointment by a trained technician, using a specialised machine. This study aims to assess whether a simple electronic skin sensor known as an accelerometer (similar to a "FitBit") can detect narrowings inside the AV fistula, by comparing the accelerometer signal waveforms with a concurrent formal Doppler study. We aim to study 60 patients with a range of well- and poorly-functioning AVF's to establish whether the technique is feasible and reliable (i.e. sensitive and specific).
Interventions
Medical students and an electronics engineer will measure the vibrations and bruit from turbulent flow in AVFs with an accelerometer and microphone (phonoangiography) placed upon the skin overlying a patient's AVF.
The procedure takes 3-5 minutes, recording flow patterns at a standardised series of sites (bottom, middle, top, needling sites, any area of perceived narrowing), according to checklist, and recorded on a standard AVF diagram.
No patient preparation is required. The examination will
Medical students and an electronics engineer will measure the vibrations and bruit from turbulent flow in AVFs with an accelerometer and microphone (phonoangiography) placed upon the skin overlying a patient's AVF. The procedure takes 3-5 minutes, recording flow patterns at a standardised series of sites (bottom, middle, top, needling sites, any area of perceived narrowing), according to checklist, and recorded on a standard AVF diagram. No patient preparation is required. The examination will be performed when patients present to the dialysis unit as soon as convenient (usually within 1-2 weeks) after a concurrent formal Doppler examination in Royal Perth Hospital Radiology Department, and physical examination by a vascular access nurse practitioner.
Sponsors
Royal Perth Hospital
Study design
Allocation
Non-randomised trial
Intervention model
Single group
Primary purpose
Diagnosis
Masking
Open (masking not used)
Eligibility
Sex/Gender
All
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
Patient has an AVF located anywhere on the forearm or upper arm, plus. ESKD patients on regular dialysis, or Pre-dialysis patients with newly-formed unused fistula
Exclusion criteria
Those with: - Previous procedures in the same limb - Infection - Pseudoaneurysms - Movement in the arm i.e. Parkinson’s - Cuts/rashes or other skin abnormalities - Prosthetic AV fistulae
Outcome results
None listed