Condition category
Date applied
Date assigned
Last edited
Prospectively registered
Overall trial status
Recruitment status

Plain English Summary

Background and study aims
After an operation, most wounds are closed using stitches or staples. Some wounds cannot be closed in this way and are left open. Sometimes wounds that have been closed may open up again. These “open” wounds are usually left to heal, over time, from the bottom up rather than attempting to close them again by some other means. The most common treatment for these wounds is plain dressings. Another type of treatment is Negative Pressure Wound Therapy (NPWT) which is a relatively new treatment for open surgical wounds. It uses a small machine to apply suction to a wound through a special dressing. Use of NPWT has become more common and is used in around one third of people with open surgical wounds. It is not known which of these (NPWT or wound dressings) is the most effective treatment for surgical wounds healing by secondary intention and which treatment is best value for money. The aim of this study is to compare NPWT to normal wound dressings to see if it makes any difference to how quickly these open wounds heal.

Who can participate?
Patients aged 16 or older with a surgical wound healing by secondary intention

What does the study involve?
Participants receive one of the two treatments (NPWT or wound dressings), selected at random using a computer system. The two groups are compared over 12 months including how long it takes their wounds to heal, number of infections, hospital admissions and further operations, and how much both treatments cost.

What are the possible benefits and risks of participating?
The information from this study may help to treat people with open wounds more effectively in the future. As with any treatment there are always potential risks, although side effects in both treatments are very uncommon. Where negative pressure wound therapy machines are used, the device may present a trip hazard and so care should be taken when moving around. Where a wound is located on the stomach, there is an increased risk of developing a fistula, an abnormal opening between organs and the skin. Where normal wound dressings are used, there may be a need for frequent dressing changes, sometimes daily. These are usually completed by a nurse. Being in this study will not harm or disadvantage participant's care in any way and participants will be monitored regularly as part of usual NHS care.

Where is the study run from?
1. Hull Royal Infirmary
2. Queen Elizabeth Medical Centre
3. Royal Liverpool University Hospital
4. Doncaster Royal Infirmary
5. Russells Hall Hospital
6. Royal Cornwall Hospital
7. Manchester University NHS Foundation Trust
8. St Mary's Hospital
9. The Freeman Hospital
10. St James' University Hospital
11. Norfolk and Norwich University Hospitals NHS Foundation Trust

When is the study starting and how long is it expected to run for?
November 2018 to April 2022

Who is funding the study?
National Institute for Health Research (NIHR) (UK)

Who is the main contact?
Catherine Arundel

Trial website

Contact information



Primary contact

Ms Catherine Arundel


Contact details

York Trials Unit
Lower Ground Floor
ARRC Building
Department of Health Science
University of York
YO10 5DD
United Kingdom
+44 (0)1904 321 116



Additional contact

Ms Catherine Arundel


Contact details

York Trials Unit
Lower Ground Floor
ARRC Building
Department of Health Science
University of York
YO10 5DD
United Kingdom
+44 (0)1904 321 116

Additional identifiers

EudraCT number

Nil known number

Nil known

Protocol/serial number

Sponsor ID: R2319; HTA 17/42/94; 40908

Study information

Scientific title

A pragmatic, multicentre, randomised controlled trial to assess the clinical and cost effectiveness of negative pressure wound therapy versus usual care for surgical wounds healing by secondary intention (SWHSI 2)



Study hypothesis

Negative Pressure Wound Therapy (NPWT) is superior to usual care in the treatment of surgical wounds healing by secondary intention (SWHSI).

Ethics approval

Yorkshire and The Humber - Leeds East, ref: 19/YH/0054 - approval pending

Study design

Pragmatic multi-centre randomised controlled trial

Primary study design


Secondary study design

Randomised controlled trial

Trial setting


Trial type


Patient information sheet

Not available in web format, please use the contact details to request a patient information sheet.


Surgical wounds healing by secondary intention


Patients with a potential planned SWHSI (pre-operatively) or a SWHSI occurring at any point following surgery will be screened for potential eligibility by their clinical care team or GP. Patients who agree to take part will receive one of the two treatments selected at random using a computer system.

Intervention: Negative Pressure Wound Therapy (NPWT).
Participants will be treated with negative pressure wound therapy (NPWT). The patients wound is filled with a suitable dressing, and a liner may also be used to protect the wound. A vacuum pump is then attached which applies suction to the wound. A disposable, plastic canister slots into the pump to collect wound exudate and this is removed and replaced either when it becomes full, or at least once a week.
The device is generally used as part of the SWHSI treatment pathway rather than to the point of healing and is administered by both nurses and clinicians.
The use of any CE marked NPWT device, providing pressure of 60-150mmHg, in use within the NHS will be permitted in this trial, given that the principles of any device are similar and there is no evidence to suggest clinical or cost-effectiveness differences between devices. The device will be used in accordance with manufacturer guidance, and the clinical care team, in conjunction with local treatment guidelines, will determine the duration of device use, and whether this includes continuous or intermittent pressure cycles.

Control: Usual Care (no NPWT)
Usual care will be that used locally, without NPWT. This is most likely to be other sorts of wound dressings and use of any dressing type will be permitted. The frequency of dressing changes will continue as per standard practice.

Participants in both groups will be followed up by telephone on a weekly basis until the participant's wound has healed. Following wound healing, three face to face visits will be completed to assess the wound, complete a wound infection assessment, and to collect photographs of the healed wound.

Participants in both groups will be asked to complete short questionnaires at 3 months, 6 months and 12 months which include assessment of pain, wound infection, quality of life and resource use.

Intervention type



Not Applicable

Drug names

Primary outcome measure

Time to healing in days from randomisation (defined using the commonly used and clinically certified criteria ‘complete epithelial cover in the absence of a scab (eschar)’). Confirmation of wound healing by a health care professional will initially be participant-reported through weekly telephone contact with the research nurse. Participants will be asked to report if their clinician or nurse has indicated that their wound is healed. In the event the participant reports their wound to be healed, but this has not been confirmed by a healthcare professional, the research nurse will contact the clinical care team to obtain this confirmation. Once wound healing has been confirmed by a healthcare professional and treatment has ceased, participants will undergo clinical assessments on three subsequent consecutive weeks during which standardised photographs will be taken of the wound for blinded outcome verification.

Secondary outcome measures

1. Clinical events including antibiotic treatment, hospital admission or discharge, treatment status (including reasons for dressing or treatment failure or change), re-operation (including skin grafting and closure surgery*), amputation and death will be assessed using clinic records and patient-reported events on a weekly basis until the point of wound healing. * The decision for closure surgery will be made blinded to treatment allocation
2. Wound infection assessed using the Bluebelle Wound Healing Questionnaire (WHQ). The questionnaire includes items to assess signs, symptoms and wound care interventions indicative of surgical site infection (SSI) and can be completed by patient self-report or by healthcare professionals. The tool may be used to assess wounds in hospital or after the patient has been discharged. The WHQ will be completed by the participants themselves at baseline, 3, 6 and 12 month follow up assessments, and will also be completed by the patient at the initial healing visit
3. Wound pain, assessed using a visual analogue scale (with anchors 0 ‘no pain’ and 10 ‘worst imaginable pain’). The scale will be completed by the participant themselves at baseline, 3, 6 and 12 month follow up assessments
4. Quality of life, measured using the EQ-5D-5L at baseline, 3 months, 6 months and 12 months follow up assessments
5. Resource use: wound-related NHS consultations, support (e.g. occupational therapy, in home adaptions) and out of pocket costs collected using a patient-reported questionnaire at baseline, 3, 6 and 12 months

Overall trial start date


Overall trial end date


Reason abandoned (if study stopped)


Participant inclusion criteria

1. Aged 16 years or over
2. Has an acute SWHSI (i.e. a wound left open as planned following surgery or a wound initially closed using sutures, clips, or other closure methods and dehisced along the whole or part of its length, and of less than 6 weeks in duration), arising from any surgical specialty and occurring on any part of the body, deemed appropriate to receive either NPWT or wound dressing treatment
3. Has a SWHSI that is considered ready for NPWT treatment (i.e. contains at least 80% viable tissue or has only a very thin layer of slough requiring no further debridement)
4. Patient is not deemed to be malnourished, as per NICE guidelines CG 32 (BMI <18.5 kg/m2; unplanned* weight loss >10% in the last 3-6 months; BMI <20kg/m2 and unplanned* weight loss >5% in the last 3-6 months) or assessed as at high risk of malnutrition using the Malnutrition Universal Screening Tool (MUST)
*Patients with weight loss arising either from underlying comorbidity (e.g. ulcerative colitis) or from the reasons for surgery being completed (e.g. bowel cancer) may be included at the clinician’s discretion
5. Willing and able to give informed consent and provide follow-up data

Participant type


Age group




Target number of participants


Participant exclusion criteria

1. Life expectancy of less than 6 months e.g. undergoing end stage palliative care
2. Active systemic infection (including osteomyelitis) at baseline as defined by clinical and/or laboratory assessment. Note: Patients who have an active infection, but are improving following 1 week’s duration of antibiotics may be included at the clinician’s discretion
3. Inadequate haemostasis or patients who are at risk of bleeding
4. Chronic wounds non-surgical in origin (e.g. pressure ulcers or foot ulcers)
5. Current wound has previously been, or is currently being, treated with NPWT
6. Planned delayed primary closure of the wound
7. Contraindication to NPWT including: presence of unclear undermining in the wound cavity; presence of necrotic tissue, malignant tissue or eschar; wounds involving exposed blood vessels and/or organs, anastomotic sites and/or nerves (including the “open abdomen” where the abdominal fascia is open); wounds situated where, in the opinion of the treating clinician, a vacuum seal cannot be obtained; presence of a non-enteric or unexplored fistula; people with a sensitivity or allergy to silver; people requiring emergency airway aspiration, pleural mediastinal or chest tube drainage or surgical suction
8. Currently participating in another wound research study, where the primary outcome time point has not yet been reached

Recruitment start date


Recruitment end date



Countries of recruitment

United Kingdom

Trial participating centre

Hull University Teaching Hospital NHS Trust
Hull Royal Infirmary Anlaby Road
United Kingdom

Trial participating centre

University Hospitals of Birmingham NHS Foundation Trust
Queen Elizabeth Medical Centre Edgbaston
B15 2TH
United Kingdom

Trial participating centre

Royal Liverpool and Broadgreen University Hospitals NHS Trust
Royal Liverpool University Hospital Prescot Street
L7 8XP
United Kingdom

Trial participating centre

Doncaster and Bassetlaw Teaching Hospitals NHS Foundation Trust
Doncaster Royal Infirmary Armthorpe Road
United Kingdom

Trial participating centre

The Dudley Group NHS Foundation Trust
Russells Hall Hospital Pensnett Road
United Kingdom

Trial participating centre

Royal Cornwall Hospitals NHS Trust
Royal Cornwall Hospital Treliske
United Kingdom

Trial participating centre

Manchester University NHS Foundation Trust
Oxford Road
M13 9WL
United Kingdom

Trial participating centre

Imperial College Healthcare NHS Trust
St Mary's Hospital Praed Street
W2 1NY
United Kingdom

Trial participating centre

The Newcastle Upon Tyne Hospitals NHS Foundation Trust
The Freeman Hospital High Heaton
United Kingdom

Trial participating centre

Leeds Teaching Hospitals NHS Trust
St James' University Hospital Beckett Street
United Kingdom

Trial participating centre

Norfolk and Norwich University Hospitals NHS Foundation Trust
Colney Lane
United Kingdom

Sponsor information


Hull University Teaching Hospital NHS Trust

Sponsor details

R&D Department
2nd Floor Daisy Building
Castle Hill Hospital
HU16 5JQ
United Kingdom
+44 (0)1482 461883

Sponsor type

Hospital/treatment centre



Funder type


Funder name

Health Technology Assessment Programme

Alternative name(s)

NIHR Health Technology Assessment Programme, HTA

Funding Body Type

government organisation

Funding Body Subtype

Federal/National Government


United Kingdom

Results and Publications

Publication and dissemination plan

Documentation relating to the study will be made available as the study progresses. Results will be published in peer reviewed journals. Summaries of the findings will be sent to NICE and other relevant bodies so that findings can inform clinical practice. The trialists will also work with the relevant National Clinical Director in the Department of Health to ensure findings are considered when implementing policy. The trialists will also work with relevant Speciality Advisory Committees to incorporate findings into training curriculum's for clinicians.

IPD sharing plans
The current data sharing plans for the current study are unknown and will be made available at a later date.

Intention to publish date


Participant level data

To be made available at a later date

Basic results (scientific)

Publication list

Publication citations

Additional files

Editorial Notes

25/03/2019: Trial's existence confirmed by the NIHR.