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

Plain English Summary

Background and study aims
Emergency abdominal operations are performed for a variety of life threatening indications, including bowel blockages or perforations, traumatic injuries and major infections. Patients are left with large wounds on the abdomen, at least 1 in 4 of which will become infected. These surgical site infections (SSIs) are painful and take longer to heal, often resulting in a longer hospital stay and greater need for further wound care in the community. In an already unwell patient, development of an SSI can contribute to other major medical complications or even death. Single use negative pressure dressings (SUNPDs) are a special type of closed wound dressing that have recently been developed. They provide gentle suction to the closed wound and may help prevent development of an SSI. Negative pressure dressings are already used for some types of wounds and have been proven to be safe. However, they are more expensive so we need to be sure that that they are effective in reducing SSI before widespread uptake can be recommended within the NHS. This study aims to test whether the use of SUNPDs can reduce rates of SSI after emergency surgery on the abdomen.

Who can participate?
Patients aged 16 and over undergoing emergency abdominal operations

What does the study involve?
Participants are randomly allocated to receive either the new SUNPD dressings or standard dressings to establish whether they are effective in reducing SSI rates. The number of SSIs and the overall costs of treatment are compared between the two groups and the acceptability of the dressings to both patients and health professionals is assessed.

What are the possible benefits and risks of participating?
There are no guaranteed direct benefits involved with participating in this study but the SUNPD dressings could be shown to be more effective than standard dressings in preventing wound infections. The risks associated with the SUNPD dressing are the same as with any dressing after surgery. There is a small risk of a skin reaction or allergy to the dressing, which might cause redness, itching, swelling or pain over the skin next to the dressing. No other risks are known.

Where is the study run from?
1. Queen Elizabeth Hospital Birmingham (UK)
2. Birmingham Heartlands Hospital (UK)
3. Sandwell General Hospital (UK)
4. Stepping Hill Hospital (UK)
5. Wythenshawe Hospital (UK)
6. Manchester Royal Infirmary (UK)
7. Royal Bolton Hospital (UK)
8. Salford Royal Hospital (UK)
9. University Hospital Coventry (UK)

When is the study starting and how long is it expected to run for?
November 2017 to July 2021

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

Who is the main contact?
Dr Laura Magill

Trial website

Contact information



Primary contact

Dr Laura Magill


Contact details

Birmingham Clinical Trials Unit
The University of Birmingham
United Kingdom
+44 (0)121 415 9105

Additional identifiers

EudraCT number number

Protocol/serial number


Study information

Scientific title

Single Use Negative pRessure dressing for Reduction In Surgical site infection following Emergency laparotomy



Study hypothesis

This study aims to test whether the use of a new type of active wound dressing (Single Use Negative Pressure Dressings ‘SUNPDs’) can reduce rates of wound infection (also called surgical site infection or ‘SSI’) after emergency surgery on the abdomen.

Ethics approval

Yorkshire & The Humber - Bradford Leeds Research Ethics Committee, 17/09/2018, ref: 18/YH/0322

Study design

Randomised; Interventional; Design type: Treatment, Device

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 wound infection


Patients will be identified as possible participants by the surgical team as they are assessed during their admission to hospital. It is likely to be the surgical registrar that identifies the patient but it may be any member of the surgical team from Foundation Year 1 doctor to Consultant.

The patient will be approached at the time that the decision to operate is made. Patients will be given a Patient Information Sheet and the trial will be discussed with them. The dressings will be fully explained and the patient will be given plenty of opportunity to ask questions. The principle of the dressings is simple to understand and our patient focus group believes that patients will be able to understand the trial concept despite the acute nature of their illness and impending surgery.

If the patient agrees to participate in the trial, they will be asked to sign a consent form. They will then undergo an operation as decided by the clinical team. The involvement in this research will have no bearing on the choice or method of operation. As long as the patient fulfils the inclusion criteria, the patient will be randomised to either a SUNPD or a standard dressing at the end of the operation. It is important that this randomisation occurs once the skin has started to be closed. This is to prevent a change in the method of skin closure once it is known which arm the patient is going to be allocated to. When the skin is closed, either a standard dressing or a SUNPD will be applied.

Patients will then undergo their normal pathway of care with no change in usual practice until post-operative day 7 or discharge (whichever is earlier). At this timepoint, the dressing will be removed and the wound will be assessed for the presence of a surgical site infection.

Upon discharge, the patient will be asked to complete a wound diary (See supporting information/documentation). This is a simple, tick box sheet that the patient will fill in each day. Every seven days the diary contains the EQ-5D-5L questionnaire for the patient to fill in. To aid the patient in filling out the diary they will be contacted once a week (by telephone or text) by the research team to remind the patient to fill in the diary and also to provide help if needed in filling it out.

The patient will be asked to return to hospital 30-37 days after their operation for a wound review. This will be by a member of the research team that does not know if the patient had a SUNPD dressing or a standard dressing applied after their operation. The researcher will inspect the wound and ask the patient a few simple questions.

If the wound has healed, the patient will have completed their involvement in the trial. If the patient has a wound that has not fully healed, they will be asked to continue in the trial. If they agree, they will be given a new wound diary and asked to complete until their wound has healed. They do not need to return for another wound check.

Intervention type



Drug names

Primary outcome measure

SSI as defined by CDC criteria; Timepoint(s): Within 30 days post-operatively. Direct wound assessment will be conducted on day 5-7 post-operation or on discharge (whichever is sooner). It will also be performed at 30 days post-operation by a blinded and trained wound assessor.

Secondary outcome measures

1. Length of hospital stay after surgery as measured from the date of surgery to the date of discharge
2. Wound complications as graded by Clavien-Dindo scale within 30 days post-surgery
3. Hospital re-admission for wound related complications within 30 days. These will include SSIs, wound breakdown/dehiscence, seromas and wound-related pain
4. Health-related quality of life assessed using the validated Short Form-12 (SF-12) questionnaire at baseline, and day 7 and day 30, and the EuroQol-5 Dimension-5 Level (EQ-5D-5L) at baseline, day 7, day 14, day 21 and day 30
5. Pain at the site of the primary laparotomy, assessed using a Likert scale of 1-10 at day 7 and day 30
6. Serious adverse events up to 30 days
7. Cost-effectiveness assessed using a patient diary for patient reported healthcare resource usage. Healthcare usage will be taken directly from the patient diaries and the costs attributable to this will be identified
8. Patient acceptability of use of their dressing via an acceptability score using a Likert scale of 1-10 at day 7, reflecting participant’s assessment of the acceptability of having the dressing
9. Health professional’s acceptability of use of SUNPD (via a survey of users at the end of the feasibility phase). This will focus on the ease of application of the dressing, the care needed to maintain/monitor the dressing while it is in place and an overall assessment of health professional’s experience of the dressing.

Overall trial start date


Overall trial end date


Reason abandoned (if study stopped)


Participant inclusion criteria

All adults undergoing emergency laparotomy surgery for any surgical indication and via any abdominal incision >5 cm

Participant type


Age group




Target number of participants

Planned Sample Size: 630; UK Sample Size: 630

Participant exclusion criteria

1. Aged less than 16 years
2. Permanent/long-term incapacity to consent
3. Procedures with an incision of less than 5 cm
4. Operations where the skin is not primarily closed
5. Abdominal surgery within the preceding three months
6. Patient unwilling or unable to attend follow-up visit at around 30 days post-operation
7. Expected return to theatre for reopening of laparotomy wound within 30 days

Recruitment start date


Recruitment end date



Countries of recruitment

United Kingdom

Trial participating centre

Queen Elizabeth Hospital Birmingham
Mindelsohn Way
B15 2WB
United Kingdom

Trial participating centre

Birmingham Heartlands Hospital
Bordesley Green East
B9 5ST
United Kingdom

Trial participating centre

Sandwell General Hospital
B71 4HJ
United Kingdom

Trial participating centre

Stepping Hill Hospital
Poplar Grove
United Kingdom

Trial participating centre

Wythenshawe Hospital
Southmoor Road
M23 9LT
United Kingdom

Trial participating centre

Manchester Royal Infirmary
Oxford Road
M13 9WL
United Kingdom

Trial participating centre

Royal Bolton Hospital
Minerva Road
United Kingdom

Trial participating centre

Salford Royal Hospital
Stott Lane
M6 8HD
United Kingdom

Trial participating centre

University Hospital Coventry
Clifford Bridge Road
United Kingdom

Sponsor information


University of Birmingham

Sponsor details

Research Governance Team
B15 2TT
United Kingdom
+44 (0)121 414 7618

Sponsor type




Funder type


Funder name

NIHR Central Commissioning Facility (CCF); Grant Codes: PB-PG-0416-20045

Alternative name(s)

Funding Body Type

Funding Body Subtype


Results and Publications

Publication and dissemination plan

The PIS and protoco will be made available on the SUNRRSIE website ( once the website is live and they have been approved. The findings will be published in international medical journals so that they can help patients globally.

IPD sharing statement
The datasets generated during and/or analysed during the current study are/will be available upon request from Dr Laura Magill ( Access to available anonymised data may be granted following review.

Intention to publish date


Participant level data

Available on request

Basic results (scientific)

Publication list

Publication citations

Additional files

Editorial Notes

02/10/2019: Internal review. 28/03/2019: The condition has been changed from "Specialty: Surgery, Primary sub-specialty: Trauma and Emergency Surgery; Health Category: Infection, Oral and Gastrointestinal; Disease/Condition: Bacterial, viral and other infectious agents" to "Surgical wound infection" following a request from the NIHR.