Int J Colorectal Dis DOI 10.1007/s00384-015-2487-0

LETTER TO THE EDITOR

Wound infection following stoma reversal: a prospective comparative study between primary closure and partial closure with intervening silver dressings N. H. Zubaidah 1 & J. Y. Soo 1 & N. Qisti 1 & K. W. Ong 1 & T. Gee 1

Accepted: 21 December 2015 # Springer-Verlag Berlin Heidelberg 2016

Dear Editor: Closure of gastrointestinal tract stoma has been traditionally regarded as a clean-contaminated operative procedure that is associated with a high incidence of surgical site infection (SSI). The stomas have an increased bio-burden due to the nature of the enteric contents. Therefore, wounds following stoma closure are likely to be contaminated. This invariably leads to surgeons in treating the wound as such with either delayed primary closure or healing by secondary intention as compared to primary closure (PC). There are relatively few studies to show that PC is as good as, if not better, than other wound closure methods in terms of SSI rates. However, to date, which method provides the least SSI rate is still a subject to debate and a consensus has yet to be achieved. As a consequence, a few modified methods of wound closure following stoma reversal have evolved to provide alternatives to PC. One of the alternative method is by closing the wound partially with interrupted sutures interspersed with dressings. Recently, there has been an increase in the use of silver as an antimicrobial agent. A silver-containing Hydrofiber dressing, Aquacel® Ag (ConvaTec), is capable of managing exudates better than conventional absorptive fibrous dressings. The core of this dressing is made of sodium carboxymethylcellulose that is designed to absorb exudate effectively subsequently releasing ionic silver into the wound environment in a

* N. H. Zubaidah [email protected]

1

Department of Surgery, Faculty of Medicine and Health Sciences, University Putra Malaysia, Serdang, Selangor, Malaysia

controlled manner. The carboxymethylcellulose and silver components therefore makes Aquacel® Ag an ideal antimicrobial dressing for contaminated wounds such as wounds following stoma reversals. Therefore, the aim of this study is to describe and evaluate a new method of wound closure following stoma reversals by performing partial closure with intervening silver dressings. A comparison of the new method is made with a PC, and the SSI rates among both these groups were studied. Although the method of using partial closure with intervening dressings has been described, the use of silver-containing dressings has yet to be elucidated. A total 44 patients were randomized into two groups from two public hospitals from January 2011 until April 2015. The study group consists of patients who had closure of the stoma via partial primary closure with intervening silver dressing using Aquacel® Ag compared with PC group. The silver dressings used in this study incorporate ionic silvercontaining Hydrofiber dressing (Aquacel® Ag) was provided by ConvaTec. None of the investigators have any interests in the company providing the silver dressings. Patients were assessed pre-operatively, during the admission for operation, at 2 weeks for SSI and at 6 weeks for wound healing. Twenty-four patients were sampled into the control group and 20 patients in the study group. The mean age for both control and study groups was between 53 years old. The gender in both the groups was predominantly male. The type of stoma of both groups was predominantly colostomy. When evaluating other variables with regard to surgical site infection, none was found to be statistically significant in increasing the risk of infection. There were two patients (8 %) of the SSI rate in the control group but zero in the study group. The healing rate was 100 % in the study group as compared to 92 % in the control group. However, both SSI and healing rate were not statically significant in this comparative study.

Int J Colorectal Dis

The care of wounds post reversal of stoma requires an exquisite balance of optimal healing with minimal infection due to its high bioburden content. Primary closure has been a routine practice for closure of stoma wounds. Studies have demonstrated higher surgical site infection in primary closure as seen in our study. Several techniques have been developed to take on the events of high bioburden in stoma wounds which was likewise reported to have lower infection rates but results were thus far inconclusive. Therefore, there was no standardized management in reversal of stoma. In this study, wound is left partially open with interrupted sutures and intervening dressings. The trade-off with leaving wounds partially open, however, is a prolonged time for final closure and increased local wound care requirements. When the hosts’ immune response is unable to cope with the opportunistic colonization, this wound may become infected and subsequently result in delayed wound healing. Health care costs will increase not forgetting the impact on patients themselves, i.e. pain, inconvenience and risk of further systemic illnesses. In general, the best possible dressing would be something that is able to provide a moist environment to help healing, causes the least discomfort for patients, and is concurrently armed with an inherent antimicrobial property. However, not all dressings are suitable for this purpose. Traditional gauze dressings lack antimicrobial property and cause more fluid depletion through evaporation, which in turn reduces the local tissue temperature at a wound site. This process depresses host immune and wound-healing function, hence increases the chances of wound infection. Gauze dressings that are dry are also often painful and adherent.

For centuries, metallic silver exhibited some antimicrobial properties; hence, it was used for water sanitation, complementary health care, and food preservation. Different antibiotics have different mechanisms of action, but in general they attack a single component of bacteria, such as the cell wall, to halt bacterial metabolism. Silver, on the other hand, attacks multiple components of bacterial metabolism. Therefore, this property makes it an effective, broad-spectrum, antimicrobial agent with relatively low bacterial resistance. Silverimpregnated dressings, hence, were used in this study. One of the major limitation of many of the available studies reported is the retrospective design of the study where outcome assessment was performed retrospectively. Our study showed a higher incidence of surgical site infection in the primary closure group (8 %) as compared to zero in partial closure with the intervening dressing group. However, there was no statistical significant difference in surgical site infection and healing rate between these two groups. The cost effectiveness and cosmetic effect between both these groups were not done. In our study, the PC group showed 8 % of wound infection rate post stoma closure which results in regular wound dressing and antibiotic usage in these patients. This has even showed delayed in wound healing at 6 weeks post stoma closure. This has the indirect financial burden to patients and to the hospital in the PC group as compared to the study group. In the partial closure with the intervening dressing group, there was zero wound infection and complete healing at 6 weeks post closure. The limitation of this study is the small sample size, which is not sufficiently representative of the population.