A randomized controlled trial comparing two wound dressings used after elective hip and knee arthroplasty

INTRODUCTION

Patients undergoing hip or knee arthroplasty are at risk of developing post-operative wound complications such as blistering, which can interfere with wound healing. It is important to prevent complications throughout the patient journey¹.

Prolonged hospitalisation, wound infections and need for further surgery are all possible complications resulting from skin breakdown in these wounds².

Management of the surgical incision site should focus on:
• minimising disturbance to the wound³
• preventing microbial invasion³
• maintaining patient comfort³

Mepilex® Border Post-Op is a self-adherent dressing that absorbs blood and wound exudate and minimises the risk of maceration. The flexible wound pad provides conformability, allowing for patient mobility, while the incorporation of soft silicone Safetac^® technology helps to minimise pain and trauma at removal.

AIMS

• The primary aim of the study was to compare the performance of two postoperative wound dressings after elective hip or knee arthroplasty in terms of post-operative wound complications.

• Secondary objectives included the evaluation of dressing performance in terms of comfort, conformability, pain before and during dressing removal and patient/clinician satisfaction.

METHODS

• This open, parallel, randomised clinical trial was conducted in three centres.

• Patients (≥18 years with expected length of post-operative hospital stay ≥4 days and planned incision size ≤18 cm) were randomised to receive either Mepilex Border Post-Op (Dressing A) (n=53) or Aquacel® Surgical (Dressing B) (n=50).

• Data were collected at baseline, on the day of surgery and during 4 postoperative days.

• The primary outcome variable was the occurrence of dressing failure. This variable was scored from 0 to 7, by making the sum of the following factors:

* At last visit, based on a 100 mm visual analogue scale (VAS)

Secondary outcome variables related to wound complications, dressing performance and safety were also monitored.

• Photographic documentation was evaluated in a blinded manner.
• A sample size calculation had identified the need for 100 patients; a total of 118 subjects were enrolled; 113 subjects were randomised either to Mepilex Border Post-Op (Dressing A) or Aquacel Surgical (Dressing B); 108 patients were followed-up (51 hip arthroplasty patients, 57 knee arthroplasty patients) and 103 patients were included in the ITT analyses.

RESULTS

• Overall, dressing A was comparable to or superior to dressing B in all parameters investigated.

• No skin tears or local/systemic infection occurred in either group, from operation day to last visit.

• No blisters occurred in the Mepilex Border Post-Op group, whereas one blister occurred in the Aquacel Surgical group.

• Dressing failure rates, skin redness and itching under the dressing and pain during dressing removal were low in both groups.

• Mepilex Border Post-Op outperformed the comparator dressing in terms of the worst outcome analysis from operation day to last visit on numbers of poor, good, very good, excellent ratings for ease of application (P<.0001) (Figure 1) and removal (P<.0001) (Figure 2), ability to handle blood (P<.0001), prevention of dressing residuals (P=.0167), patient satisfaction of wearing the dressing during rehabilitation training (P=0.0037) (Figure 3) and patients’ overall experience with the dressing (P=.0025) (Figure 4) in the ITT population.

• The number of patients who had a dressing change was low in both groups (7 (13.2%) in the Mepilex Border Post-Op group and 5 (10%) in the Aquacel Surgical group), with no significant difference between the two groups (ITT population).

CONCLUSIONS

Both dressings performed well in terms of minimising post-operative wound complications. However, clinicians found Mepilex Border Post-Op to be superior to the comparator dressing in terms of satisfaction of applying and removing the dressing. Furthermore, those patients treated with Mepilex Border Post-Op reported greater satisfaction with the dressing, which is likely to contribute to a higher level of compliance. These results suggest that Mepilex Border Post-Op should be considered as a good choice post-operative wound dressing.

References: 

1. Tustanowski, J. Effect of dressing choice on outcomes after hip and knee arthroplasty: a literature review. Journal of Wound Care 2009; 18(11):449-454.
2. Zarghooni, K., Bredow, J., Siewe, J., Deutloff, N., Meyer, HS., Lohmann, C. Is the use of modern versus conventional wound dressings warranted after primary knee and hip arthroplasty? Results of a prospective comparative study. Acta Orthopaedica
3. Deegan, R., Churchman, A. Evaluation of dressings in the care of wounds following orthopaedic surgery. Poster presentation at Wounds UK Conference, Harrogate, 2014