The present study suggests a potential benefit associated with the systematic application of a closed-wound NPWT device after loop ostomy closure. Technical issues were very uncommon. Adequately powered studies are needed to confirm these preliminary findings.
Negative pressure wound therapy has been established as a SSI preventing measure for several different indications, especially in colorectal surgery [7]. However, the NEPTUNE trial did not describe NPWT as superior to classical wound closure [13].
Nevertheless, a few studies assessed the effect of NPWT application after loop ostomy closure [8-10]. A recently published randomized controlled study of NPWT in primarily closed wounds after loop ileostomy closure described a iSSI rate of 5.7% in the NPWT group vs. 19% without NPWT [9]. The present series revealed a similar rate of iSSI in the NPWT group, but lower rates in the control group, which may explain the lack of significant difference in the present comparison. A recent observational study from Japan evaluating an open-wound VAC therapy system customized for closed wounds did not report any SSI in 50 patients after ileostomy closure [10]. While their results were promising, the customized technique of NPWT application on open wounds may be difficult to apply on a large scale.
In this present series, NPWT dressings were well-tolerated and easy to use, with only exceptional technical issues. Surgical duration was slightly longer, which however may also be related to constitutional factors (higher BMI and comorbidity indices in the NPWT group). The main advantage probably consists in simplified post-operative wound care, unlike the time-consuming purse-string closure. While several reports revealed lower SSI rates after purse-string closure compared to primary closure [4, 5], wounds require daily care until discharge and specialist wound care for about 35 days according to our institutional experience (4) and a previous report [14]. In contrast, primarily closed ostomy wounds without SSI occurrence typically heal within 7-24 days [4, 9]. The intradermal suture is further convenient since no follow-up care is needed after device removal providing uneventful wound healing.
The present study has several limitations related to the small sample size and uncontrolled setting. However, all consecutive patients were included. Based on the positive preliminary experience of other series, our group decided to implement closed-wound NPWT therapy as a new standard of care (practice change) and to compare outcomes to the unselected pre-implementation cohort. This design was chosen given the consistency of surgical and perioperative care and standardized, prospective SSI surveillance based on our institutional ERAS protocol [15].
An adequately powered randomized controlled multicentric trial comparing different techniques and considering patient preference might probably be the most appropriate way to further optimize ostomy wound management. The ongoing SR-PICO randomized study (KCT0004063) may confirm our preliminary results [16].
In conclusion, additional closed-wound NPWT dressings after primary skin closure of ostomy wounds seems beneficial in reducing iSSI. This strategy challenges the purse-string closure method in ease of management, reduction of resources and time to complete wound healing.