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Trial registered on ANZCTR


Registration number
ACTRN12624000949583
Ethics application status
Approved
Date submitted
23/07/2024
Date registered
5/08/2024
Date last updated
5/08/2024
Date data sharing statement initially provided
5/08/2024
Type of registration
Retrospectively registered

Titles & IDs
Public title
A Prospective randomised controlled trial of low-frequency ultrasound debridement (LFUD) for lower limb wounds
Scientific title
A Prospective randomised controlled trial of low-frequency ultrasound debridement (LFUD) for adult patients with hard-to-heal lower limb wounds
Secondary ID [1] 312588 0
None
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Chronic Venous insufficiency 334516 0
Lower Limb Ulcers 334517 0
Condition category
Condition code
Cardiovascular 331131 331131 0 0
Diseases of the vasculature and circulation including the lymphatic system
Surgery 331132 331132 0 0
Surgical techniques

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Participants in the treatment group underwent Low frequency Ultrasound Debridement (LFUD). LFUD using the MIST system (Celleration, Inc, Eden Prairie, MN) was carried out by a wound specialist nurse twice weekly for 3 weeks. This procedure is carried out with a wand that produces a low-energy ultrasound-generated mist with saline. This emulsifies dead and dying tissues with microsized gas bubbles. Each LFUD treatment session lasted approximately 45 minutes. The treatment course was repeated if clinically indicated by a vascular surgeon. In most cases, LFUD was performed on the ward or in an outpatient clinic. The type of anaesthetic used depended on wound type and level of patient discomfort. This included topical anaesthetic and/or local infiltration, Entonox gas, and regional or general anaesthetic as required. Hydrogel was used as an autolytic agent. Antimicrobial dressings (silver) and/or oral antibiotics were given if clinically indicated. The wound care specialist involved in each session ensured adherence to the debridement protocol and recorded when patients were considered fully healed
Intervention code [1] 329106 0
Treatment: Surgery
Intervention code [2] 329211 0
Treatment: Devices
Comparator / control treatment
Standard wound debridement (sharp). Sharp debridement was carried out by a vascular surgeon or a wound specialist nurse. First, the healthcare provider assessed the wound, including its size, depth, and the extent of necrotic tissue.
The patient was then informed about the procedure, its benefits, risks, and any potential discomfort. Informed consent is obtained. The type of anaesthetic used depended on wound type and level of patient discomfort.
The wound area was cleaned and disinfected to reduce the risk of infection. Following cleaning, the healthcare provider used sterile instruments to carefully cut away dead or damaged tissue. This included cutting away necrotic tissue, shaping the wound edges to encourage better healing, and carefully removing tissue in layers to avoid damaging underlying healthy structures. Any bleeding was managed using techniques like applying pressure, using haemostatic agents, or cauterisation.
Control group
Active

Outcomes
Primary outcome [1] 338884 0
Change in wound size (area)
Timepoint [1] 338884 0
baseline, and weeks 4, 8, 12, 24 (primary endpoint) and 52 post-intervention commencement
Secondary outcome [1] 437789 0
Number of hospital admissions
Timepoint [1] 437789 0
From enrollment to trial completion, assessed at discharge.
Secondary outcome [2] 437790 0
Length of Hospital stay (days)
Timepoint [2] 437790 0
From enrollment to trial completion, assessed at discharge
Secondary outcome [3] 437791 0
Main operating theatre visits
Timepoint [3] 437791 0
from enrollment to trial completion, which is assessed at discharge.
Secondary outcome [4] 437792 0
Time to healing
Timepoint [4] 437792 0
from enrollment to trial completion, which is assessed at discharge.
Secondary outcome [5] 437793 0
Adverse outcomes
Timepoint [5] 437793 0
Assessments were made at weeks 4, 8, 12, 24 and 52, which is assessed at discharge.

Eligibility
Key inclusion criteria
Male and female adults with lower limb wounds requiring debridement.
Minimum age
18 Years
Maximum age
No limit
Sex
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
Participants were excluded if they were not able to attend follow-up, or if a biopsy confirmed skin malignancy or vasculitis.

Study design
Purpose of the study
Treatment
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
sealed opaque envelopes by ulcer aetiology: neuropathic, ischaemic, venous, other
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
sequences were generated by the study biostatistician using STATA
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?



Intervention assignment
Parallel
Other design features
Phase
Not Applicable
Type of endpoint/s
Efficacy
Statistical methods / analysis
Given the abandonment of the initial sample size target, making the present study underpowered for effect sizes considered of interest at its outset, a Bayesian approach was taken to support both the planned analyses and exploratory analyses based on literature that emerged subsequent to the start of the study. Stata 17 was used for all analyses and Stata’s default options were generally retained, including the use of an adaptive Metropolis–Hastings sampling algorithm, with points of particular importance and all changes from the defaults noted here. Appropriate forms of regression were used with minimally informative priors. For mixed ordinal logistic regression (used for wound size at 4, 8, 12, 24, and 52 weeks, with baseline size included as a covariate), these were Gaussian priors with very high standard deviations [10000] for all fixed effects and flat priors for cut-points; an inverse gamma [0.01, 0.01] distribution was used for the variance of the patient random effect). Negative binomial regression was used for the total number of admissions, total number of admissions related to the reference ulcer, total length of stay relating to the reference ulcer, and number of main operating theatre (MOT) visits for the reference ulcer (given overdispersion in the conditional distribution of these). Again, minimally informative priors were used, namely Gaussian priors with a very high standard deviation (10000) for all fixed effects, including the intercept, and for the log of the dispersion parameter. Analyses were repeated for the venous subtype. For all analyses, traces were inspected, along with considering autocorrelations and acceptance rates. 5000 burn-in samples were found to be adequate in all cases and 5 chains, each of 10000 samples after thinning (keeping every tenth), were used to assess stability. All models using the full data set included the randomisation strata as a covariate. To summarise results in the text, 95% credible intervals are presented (with equal tails) for all estimates of interest.

Recruitment
Recruitment status
Stopped early
Data analysis
Data analysis is complete
Reason for early stopping/withdrawal
Lack of funding/staff/facilities
Participant recruitment difficulties
Date of first participant enrolment
Anticipated
Actual
2/03/2015
Date of last participant enrolment
Anticipated
Actual
2/12/2019
Date of last data collection
Anticipated
Actual
7/12/2020
Sample size
Target
124
Accrual to date
Final
100
Recruitment outside Australia
Country [1] 26448 0
New Zealand
State/province [1] 26448 0
Otago

Funding & Sponsors
Funding source category [1] 317019 0
Charities/Societies/Foundations
Name [1] 317019 0
Southern Wound Healing Group
Country [1] 317019 0
New Zealand
Primary sponsor type
University
Name
University of Otago
Address
Country
New Zealand
Secondary sponsor category [1] 319264 0
Hospital
Name [1] 319264 0
Dunedin Hospital
Address [1] 319264 0
Country [1] 319264 0
New Zealand

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 315775 0
Northern B Health and Disability Ethics Committee 
Ethics committee address [1] 315775 0
https://ethics.health.govt.nz/about/northern-b-health-and-disability-ethics-committee/
Ethics committee country [1] 315775 0
New Zealand
Date submitted for ethics approval [1] 315775 0
14/07/2014
Approval date [1] 315775 0
01/10/2014
Ethics approval number [1] 315775 0
14/NTB/96/AM01

Summary
Brief summary
The aim of this pragmatic, prospective randomised study was to assess the benefit of LFUD in helping manage acute and chronic lower limb wounds. Patients were randomly allocated to receive low-frequency ultrasound debridement plus standard care or standard care (SC) and were assessed at weeks 4, 8, 12, 24, and 52. Wound size, length of hospital stay, theatre visit, operative time, and number of treatments were compared between treatment groups.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 135758 0
Mrs Jolanta Krysa
Address 135758 0
Department of Surgical Sciences, University of Otago, PO Box 56 Dunedin 9016
Country 135758 0
New Zealand
Phone 135758 0
+64 34709853
Fax 135758 0
Email 135758 0
[email protected]
Contact person for public queries
Name 135759 0
Kari Clifford
Address 135759 0
Department of Surgical Sciences, University of Otago, PO Box 56 Dunedin 9016
Country 135759 0
New Zealand
Phone 135759 0
+64 34709853
Fax 135759 0
Email 135759 0
[email protected]
Contact person for scientific queries
Name 135760 0
Kari Clifford
Address 135760 0
Department of Surgical Sciences, University of Otago, PO Box 56 Dunedin 9016
Country 135760 0
New Zealand
Phone 135760 0
+64 34709853
Fax 135760 0
Email 135760 0
[email protected]

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
Yes
What data in particular will be shared?
anonymised individual participant data
When will data be available (start and end dates)?
From the date of study publication in a peer reviewed journal to ten years afterwards.
Available to whom?
Other researchers
Available for what types of analyses?
any types of analyses
How or where can data be obtained?
Data can be obtained by emailing the study contact person, [email protected]


What supporting documents are/will be available?

No Supporting Document Provided



Results publications and other study-related documents

Documents added manually
No documents have been uploaded by study researchers.

Documents added automatically
No additional documents have been identified.