Accessibility statement

SWHSI-2 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

After an operation, most wounds are closed using stiches 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. Negative Pressure Wound Therapy (NPWT) is a relatively new treatment for open surgical wounds. It uses a small machine to apply gentle suction to a wound through a special dressing. This removes wound fluid, may keep the wound clean and may help with healing. 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 is the most effective treatment for surgical wounds healing by secondary intention.

The SWHSI-2 Trial compared NPWT with normal dressings to see if it made any difference to how quickly these open wounds heal. 
The study recruited from 28 NHS hospital or community sites, and randomised 686 participants (total 98.5% of target)  and patients received either NPWT or usual care. The primary outcome was time to wound healing in days since randomisation. The associated costs of these treatments to the NHS was also evaluated.

The study was being run by the Hull University Teaching Hospitals NHS Trust and the University of York, with funding from the National Institute for Health Research Health Technology Assessment Programme (Ref:17/42/94). Professor Ian Chetter was the Chief Investigator. 

Outputs

Summary of the results in an animation

https://www.youtube.com/watch?v=f7VZ_dDJtio

Protocol: Chetter, I., Arundel, C., Martin, B.C. et al. Negative pressure wound therapy versus usual care for surgical wounds healing by secondary intention (SWHSI-2 trial): study protocol for a pragmatic, multicentre, cross surgical specialty, randomised controlled trial. Trials 22, 739 (2021). https://doi.org/10.1186/s13063-021-05662-2

Results: Arundel, C. E., Mandefield, L., Fairhurst, C. M., Baird, K., Gkekas, A., Saramago Goncalves, P. R., Chetter, I., Corbacho, B., Hewitt, C. E., Mott, A., Swan, S., Torgerson, D. J., Wilkinson, J., Zahra, S., Blazeby, J., Macefield, R., Dixon, S., Hatfield, J., Oswald, A., ... Packer, E. (2025). Negative Pressure Wound Therapy versus usual care in patients with surgical wounds healing by secondary intention (SWHSI-2): an open, UK, multi-centre, parallel randomised clinical trial. Lancet (London, England), 405(10490), 1689-1699. https://doi.org/10.1016/S0140-6736(25)00143-6

Cost Effectiveness: Pedro Saramago, Athanasios Gkekas, Catherine E Arundel, Ian C Chetter, the SWHSI-2 Trial Investigators , Negative pressure wound therapy for surgical wounds healing by secondary intention is not cost-effective, BJS, Volume 112, Issue 5, May 2025, znaf077, https://doi.org/10.1093/bjs/znaf077

HTA: Arundel C, Mandefield L, Fairhurst C, Baird K, Saramago P, Gkekas A, et al. Clinical and cost-effectiveness of negative pressure wound therapy versus usual care for surgical wounds healing by secondary intention: the SWHSI 2 pragmatic RCT. Health Technol Assess 2026;30(32). https://doi.org/10.3310/GJIC1716

Arundel, C., Zahra, S., Chetter, I. et al. Surgical wounds healing by Secondary Intention-2 Trial: outcomes and learning from the internal pilot phase and main trial. Pilot Feasibility Stud 11, 90 (2025). https://doi.org/10.1186/s40814-025-01658-w

Macefield, R., Mandefield, L., Blazeby, J. M., Fairhurst, C. M., Baird, K., Arundel, C. E., Chetter, I., Corbacho, B., Hewitt, C., Gkekas, A., Mot, A., Saramago Goncalves, P., Swan, S., Torgerson, D., Wilkinson, J., Zahra, S., Dixon, S., Hatfield, J., Oswald, A., ... Parker, E. (2025). Modification and validation of the Bluebelle Wound Healing Questionnaire (WHQ) for assessing surgical site infection in wounds healing by secondary intention  . Journal of tissue viability, 34, Article 100889. https://doi.org/10.1016/j.jtv.2025.100889

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Funding

Funder (s): NIHR HTA 
Start Date: November 2018
End Date:  October 2022

Members

Internal Staff:

External Collaborators:

  • Ian Chetter, Hull and East Yorkshire Hospitals NHS Trust/HYMS
  • Karen Armstrong-Lamb, Leeds Community NHS Trust
  • Nikki Stubbs, Leeds Community NHS Trust
  • Jane Blazeby, University of Bristol
  • Rhiannon Macefield, University of Bristol
  • Jo Dumville, University of Manchester
  • Eileen Henderson, Hull and East Yorkshire Hospitals NHS Trust
  • Angela Oswald, Hull and East Yorkshire Hospitals NHS Trust
  • Matthew Lee, University of Sheffield
  • Thomas Pinkney, University Hospitals of Birmingham NHS Foundation Trust
  • Stephen Dixon, PPI representative