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Trial registered on ANZCTR


Registration number
ACTRN12619001140145
Ethics application status
Approved
Date submitted
2/08/2019
Date registered
15/08/2019
Date last updated
21/04/2021
Date data sharing statement initially provided
15/08/2019
Date results information initially provided
21/04/2021
Type of registration
Prospectively registered

Titles & IDs
Public title
Patient-controlled transcutaneous electrical nerve stimulation for postoperative pain after abdominal surgery: a randomized pilot trial in an enhanced recovery after surgery hospital
Scientific title
Patient-controlled transcutaneous electrical nerve stimulation for postoperative pain after abdominal surgery: a randomized pilot trial in an enhanced recovery after surgery hospital
Secondary ID [1] 298900 0
None
Universal Trial Number (UTN)
U1111-1232-8888
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Postoperative pain 313887 0
Condition category
Condition code
Anaesthesiology 312302 312302 0 0
Pain management

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Patients will be allocated into 2 groups, both receiving the intervention at different intensities. Group 1 will have TENS applied and titrated to a stimulation intensity that is the maximal tolerable by the patient without being painful or inducing muscle contraction. Stimulation intensity set by each individual patient at the start of each session whereby patients will titrate it up. Once patients are satisfied with intensity, patients will be instructed not to change it for the rest of the session. It is anticipated final intensity will be approximately 30mA based on previous studies but this will vary depending on what the patient deems non-painful. There is no minimum/maximum intensity provided.

After the patient is taught how to administer the treatment by a study investigator, the patient will self-administer the treatment postoperatively. Patients will receive a TENS unit providing an asymmetric square biphasic wave form at a frequency of 80 pulses/s and a pulse width of 250 µs. TENS will be applied starting 1 hour post-surgery once patients are awake and alert, with each session applied for a duration of 30 minutes for the first 48hours postoperatively. Patients will be instructed to apply the TENS when they feel pain for pre-set 30-minute durations. Patients can terminate the session early if they experience discomfort or want to; we will ask patients to record events like this. The intervention will occur on the hospital recovery ward. Patients will be given a written form to track the intensity, timing and duration of each application. The TENS machine will be modified so only intensity can be changed to prevent tampering. Patients and the TENS unit will be checked on twice daily to monitor adherence.
Intervention code [1] 315187 0
Treatment: Devices
Comparator / control treatment
Group 2 will have TENS applied and titrated to a stimulation intensity that is at the minimal sensory threshold where patients feel a faint tingling sensation from TENS application.
The use of a control group using a sham (inactive) TENS unit was decided against as previous attempts to blind TENS have been unable to produce reliable patient blinding in sham groups - we will attempt to investigate if a dose-dependent relationship can be shown.

Stimulation intensity set by each individual patient at the start of each session whereby patients will titrate it up. Once patients are satisfied with intensity (just above sensory threshold for Group 2), patients will be instructed not to change it for the rest of the session. It is anticipated final intensity will be approximately 5mA based on previous studies but this will vary depending on what the patient deems non-painful. There is no minimum/maximum intensity provided.

After the patient is taught how to administer the treatment by a study investigator, the patient will self-administer the treatment postoperatively. Patients will receive a TENS unit providing an asymmetric square biphasic wave form at a frequency of 80 pulses/s and a pulse width of 250 µs. TENS will be applied starting 1 hour post-surgery once patients are awake and alert, with each session applied for a duration of 30 minutes for the first 48hours postoperatively. Patients will be instructed to apply the TENS when they feel pain for pre-set 30-minute durations. Patients can terminate the session early if they experience discomfort or want to; we will ask patients to record events like this. The intervention will occur on the hospital recovery ward. Patients will be given a written form to track the intensity, timing and duration of each application. The TENS machine will be modified so only intensity can be changed to prevent tampering. Patients and the TENS unit will be checked on twice daily to monitor adherence.
Control group
Dose comparison

Outcomes
Primary outcome [1] 320938 0
Tolerability of patient-controlled TENS use measured by incidence of side effects: skin irritation
- skin irritation will be patient reported. A case of skin irritation will be defined as skin discomfort requiring the patient to terminate their 30-min TENS treatment session prematurely.
Timepoint [1] 320938 0
Measured on discharge/48-hours postoperatively
Primary outcome [2] 321013 0
Adequacy of patient blinding to their group allocation measured by a post-study questionnaire. This questionnaire is a yes/no questionnaire to determine what the group allocation the patient thought they were in and will be compared to their actual allocation.
Timepoint [2] 321013 0
48 hours/On discharge
Secondary outcome [1] 373416 0
Postoperative opioid use

Timepoint [1] 373416 0
On postoperative day 0, postoperative day 1 (morning and evening), postoperative day 2 (morning and evening). This will be assessed from the medical records.
Secondary outcome [2] 373687 0
Pain scores measured by numerical rating 0-10 scale (NRS)
Timepoint [2] 373687 0
On postoperative day 0, postoperative day 1 (morning and evening), postoperative day 2 (morning and evening). This will be verbally assessed.
Secondary outcome [3] 373688 0
Time to first stool
Timepoint [3] 373688 0
Postoperatively - depending on surgical recovery. This will be assessed by asking the patient to report the approximate hour of first stool each time they are assessed for other outcomes.
Secondary outcome [4] 373689 0
Time to tolerance of an oral diet
Timepoint [4] 373689 0
Postoperatively - timepoint depending on surgical recovery.
Will be defined as first intake of solid fool tolerated without nausea or vomiting. This will be assessed by asking the patient to report the approximate hour of first stool each time they are assessed for other outcomes.
Secondary outcome [5] 373690 0
Surgical complications such as postoperative nausea and vomiting, reoperation, wound infection.
Timepoint [5] 373690 0
Will be recorded as incidence postoperatively and based on medical notes.
Complications will be classified via Clavien-Dindo scoring

Eligibility
Key inclusion criteria
- Patients undergoing open or laparoscopic (with an extraction site via a mini-laparotomy) abdominal surgery at Auckland District Health Board
- Able to understand risks and benefits of participating in the study
- Ability to provide informed consent
Minimum age
18 Years
Maximum age
80 Years
Sex
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
- Prior TENS use preventing adequate study group blinding
- Current pregnancy
- Epilepsy or prior history of seizures
- History of cardiac disease
- Implantable medical device such as pacemaker or implantable defibrillator
- ASA Grade IV or greater
- Inability to participate in post-operative assessments due to dementia, cognitive impairment, language difficulties, delirium
- Inability to operate TENS device by themselves

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)
Allocation sequence will be concealed from the study team and kept in opaque numbered envelops in a secure central location. Assignment will be completed on the day of surgery.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Computer-randomization will be used to generate a number list.
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?
The people receiving the treatment/s

The people assessing the outcomes
Intervention assignment
Parallel
Other design features
Phase
Not Applicable
Type of endpoint/s
Safety/efficacy
Statistical methods / analysis
As this is a pilot trial not powered to show differences in endpoints, a qualitative analysis of primary outcomes will be completed. Statistical analysis will not be conducted on secondary outcomes.

Recruitment
Recruitment status
Completed
Date of first participant enrolment
Anticipated
Actual
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
Accrual to date
Final
Recruitment outside Australia
Country [1] 21738 0
New Zealand
State/province [1] 21738 0
Auckland

Funding & Sponsors
Funding source category [1] 303444 0
Government body
Name [1] 303444 0
Health and Research Council New Zealand
Country [1] 303444 0
New Zealand
Primary sponsor type
University
Name
University of Auckland
Address
85 Park Road, Grafton, Auckland 1145
Country
New Zealand
Secondary sponsor category [1] 303498 0
None
Name [1] 303498 0
Address [1] 303498 0
Country [1] 303498 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 303977 0
Health and Disability Ethics Committee
Ethics committee address [1] 303977 0
Ministry of Health
Health and Disability Ethics Committees
PO Box 5013
Wellington 6140
Ethics committee country [1] 303977 0
New Zealand
Date submitted for ethics approval [1] 303977 0
10/05/2019
Approval date [1] 303977 0
11/06/2019
Ethics approval number [1] 303977 0
19/CEN/80

Summary
Brief summary
The main aim of this study is to perform a pilot trial to determine if patient-controlled TENS applied in the immediate postoperative period is feasible and tolerable for patients undergoing major abdominal surgery within an ERAS protocol for the reduction of opioid use, pain, and the improvement of surgical recovery outcomes. Our hypothesis is that TENS is a patient-tolerable intervention with little to no side effects. We predict TENS will be easy and safe for patients to use. Although this study will not be powered for testing efficacy of TENS, we hypothesise that TENS when applied with enough stimulation intensity will be effective in reducing postoperative opioid use.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 95434 0
A/Prof Greg O'Grady
Address 95434 0
Department of Surgery
University of Auckland
ACH Support Building
Level 12, Room 087
Park Road, Grafton 1145
Country 95434 0
New Zealand
Phone 95434 0
+64 274 222 989
Fax 95434 0
Email 95434 0
Contact person for public queries
Name 95435 0
Mr William Xu
Address 95435 0
Department of Surgery
University of Auckland
ACH Support Building
Level 12, Room 087
Park Road, Grafton 1145
Country 95435 0
New Zealand
Phone 95435 0
+64 220720818
Fax 95435 0
Email 95435 0
Contact person for scientific queries
Name 95436 0
Mr William Xu
Address 95436 0
Department of Surgery
University of Auckland
ACH Support Building
Level 12, Room 087
Park Road, Grafton 1145
Country 95436 0
New Zealand
Phone 95436 0
+64 220720818
Fax 95436 0
Email 95436 0

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
Yes
What data in particular will be shared?
Quantitative results will be available. Qualitative surveys of patient tolerability will be deidentified first
When will data be available (start and end dates)?
IPD will be available from 01/07/2020 to 01/07/2022
Available to whom?
Will be available to other researchers/clinicians on request
Available for what types of analyses?
Quantitative analysis
How or where can data be obtained?
On request from authors via email
([email protected]
OR [email protected])


What supporting documents are/will be available?

No Supporting Document Provided



Results publications and other study-related documents

Documents added manually
TypeIs Peer Reviewed?DOICitations or Other DetailsAttachment
Study results articleYes Xu W, Varghese C, Wells CI, Bissett IP, O’Grady G.... [More Details]

Documents added automatically
SourceTitleYear of PublicationDOI
EmbasePatient-Administered Transcutaneous Electrical Nerve Stimulation for Postoperative Pain Control After Laparoscopic Cholecystectomy: A Randomized, Sham-Controlled Feasibility Trial.2020https://dx.doi.org/10.1111/ner.13242
N.B. These documents automatically identified may not have been verified by the study sponsor.