Clinical Relevance of Closed-Incision Negative Pressure Therapy (ciNPT) for SSI-Risk Reduction in Vascular Surgery Through a Groin Incision

Background: Vascular surgery, especially lower limb revascularization surgery, has one of the highest rates of surgical complications, predominantly surgical site infections (SSI). Resulting in a significant burden of additional costs due to longer hospital stays, re-admissions and reinterventions, mainly attributable to deep incisional SSIs. Closed incisional negative pressure therapy (ciNPT) is a relatively new strategy in the postoperative management surgical wounds, aiming to reduce surgical wound complications. When discussing the clinical relevance of ciNPT, it is crucial to take into account the outcome of therapy as well as the additional costs related to ciNPT. Since, the additional costs must be justified by an associated decrease in the morbidity and costs associated with groin wound complications, which are particularly attributable to deep incisional SSIs. The current literature evaluating the beneficial effect of ciNPT in groin incisional vascular surgery, predominantly focusses on the decrease in superficial SSIs. Whereas this study aims to address and discuss the clinical relevance of ciNPT over conventional wound dressings, by separately evaluating and comparing the incidence of superficial and deep SSIs and their related re-admissions and re-interventions. Methods: In this single center prospective cohort study performed in a non-academic hospital in The Netherlands, 59 consecutive patients (67 incisions) were included between January and October 2019. All underwent elective vascular surgery with groin (access) incisions for either lower limb revascularization surgery or abdominal aortic aneurysm surgery. The study group was treated with six days ciNPT (PREVENA Incision Management System; KCI/3M, San Antonio, TX, USA) and matched for equal comparison to a historical retrospectively analysed cohort of 54 consecutive patients (60 incisions), all of whom have undergone elective vascular surgery for equal indications with groin (access) incisions in our center between January and October 2018. The standard-care group was treated following standard surgical wound care protocol with conventional surgical self-adhesive plaster (10 x 15cm, Mepore, Molnlycke Health Care AB, Gothenburg, Sweden). Results: Study groups were comparable at baseline, except for Body Mass Index (BMI), which was significantly higher in the ciNPT-group (P =.021). No significant differences for formation of seroma, hematoma, as well as wound dehiscence and SSIs were found between both groups. Groin SSIs were seen in 12.1% of the patients in the ciNPT-group and in 13.0% in the Standardcare group (OR 0.80, CI ((0.26, 2.48)), deep SSI contributed for 4 out of 7 patients of total SSIs in the ciNPT-group and for 2 out of 7 patients in the standard of care group (P-value >0.05). Analysis for incidence of hospital re-admission and re-intervention in both study groups showed no significant difference. Subset analysis in both study groups for SSIs differentiated in superficial and deep SSIs showed that only deep SSIs resulted in re-interventions. Conclusions: Based on the findings in the population of our single center study, we conclude that routine use of ciNPT was not effective in reducing groin wound complications, and therefore could not replicate the promising findings from some previous studies. Furthermore, we did not find a reduction in the incidence of deep SSIs, which comprise the highest morbidity and costs. Considering our findings as well as the associated additional expenses related to ciNPT, it might be superfluous at this stage to use ciNPT as the new standard of post-operative groin incision care for all lower limb revascularization and abdominal aortic aneurysm surgeries. In our opinion further research is warranted for establishing a risk-factor based model for determination of the indication of ciNPT. To be able to achieve a more substantiated decision for utilizing ciNPT compared to standard surgical wound care in groin incisional vascular surgical interventions.