Abstract
Abstract
Background:
The management of incisions and decisions on closure techniques for surgical wounds are driven by expected incisional morbidity and the severity of the potential morbidity for the patient.
Methods:
This article reviews current literature on the potential strategies to be considered in closing the skin and fascia of incisions.
Results:
The review of the literature indicates that low-risk wounds for infection should be closed primarily with subcuticular suture, and adjunctive local measures should be avoided. Adjunctive measures of irrigation, topical antimicrobial agents, and negative pressure incisional therapy may have a role in high-risk wounds. Surgeons should strongly consider primary closure of contaminated wounds.
Conclusions:
The overall literature on adjuncts of wound irrigation, topical antimicrobials, and negative pressure wound therapy have potential to be of benefit but additional investigation is necessary since they do impact cost, patient experience, and antibiotic stewardship.
T
Closures
Fascial closure
Often overlooked, fascial closure can play an essential role in the outcome of a surgical wound. The traditional method of fascial closure employs large fascial bites 1 cm from the fascial edge placed 1 cm apart. An alternative method of fascial closure is the “short stitch” or “small bite” technique [1]. The short stitch technique uses a 2-0 monofilament suture on an MH-1 needle. Both the suture size and needle size are smaller than what most would use typically for fascial closure. Stitches are placed in the facial aponeurosis without incorporation of any muscle at a distance 5–8 mm from the wound edge and every 4–5 mm apart. A single suture is used with self-locking knots placed at the beginning and the end.
The suture to wound length ratio is felt to be a critical component of this technique. Because the recommendation is to use a single running suture, this ratio can be calculated by subtracting the remnant lengths of the starting knot and finishing knot from the total suture length and dividing this by the length of the wound. The suture to wound length ratio should be greater than 4:1 to be considered acceptable.
The short stitch fascial closure technique is thought to cause less tissue trauma and ischemia while distributing forces more evenly along the closure. Multiple randomized control trials (RCTs) have demonstrated these benefits including the initial study of 737 patients by Millbourn et al. [1], showing a significant reduction in SSIs from 10.2% with a traditional mass closure to 5.2% with the short stitch [2]. In addition, there was a significant reduction in incisional hernia formation (18% vs. 5%) at one year follow-up. This study was repeated as a multi-institutional STITCH trial in Europe in 2015 confirming these results and concluding that the short stitch or small bites technique should become the standard closure technique for midline fascial closures [2].
Skin closure
The rate of SSIs after a CDC Class I wound procedure are between 2% and 5% [3]. While every SSI has a tremendous impact on the individual patient, this is still a relatively low event rate. As such, optimizing this already low rate event has led to some technical considerations and skin closure adjuncts, such as wound irrigation, topical antibiotic agents, and negative pressure wound therapy (NPWT), to strive for the lowest possible wound morbidity. What should not be lost in this discussion is the surgical practice of proper tissue handling, which may be as impactful as any of the following closure techniques or adjuncts. In addition, patient optimization through surgical pre-habilitation can reduce excess body weight, lead to smoking cessation, and lower baseline glucose levels in patients with diabetes, also improving wound outcomes.
Stapled closure of skin incisions has been popularized by the rapidity in which a stapled closure can occur in comparison with a sutured closure [4]; however, the question of infectious complications between these two methods remains debated in the literature. Interestingly, there is a lack of data to guide surgeons on the closure of CDC I abdominal incisions. This has been studied more extensively in both the orthopedic and cardiac literature. Krishnan et al. [4], reviewed 13 studies in a meta-analysis of sutured versus stapled skin closure within orthopedics including 10 RCTs. They found that there was no significant difference in infections (odds ratio [OR] 1.06; 95% confidence interval [CI]: 0.46–2.44) and wound dehiscence (OR 0.96; 95% CI: 0.32–2.84); however, closure time was significantly reduced with staples. Similarly, a Cochrane review of three RCTs including 148 leg wounds after saphenous vein graft harvest for cardiac operation demonstrated no significant difference in infection rates (10.8% sutured vs. 8.0% stapled) or skin dehiscence (9.3% vs. 8.8%) [5].
In determining the best method of skin closure for a clean wound, consider these findings from a value perspective. Value equals outcomes divided by cost. Thus, considering that there is no difference in outcomes and that there is a reduction in operating room time utilization, which cost less than a stapler, these findings would favor the use of a stapler. Patient-reported outcomes, however, have not been reported in these studies, yet they do play a role in determining value; outcomes include not only wound complications, but also patient satisfaction, including cosmesis. As a result, patient-reported outcomes should be considered when determining the optimal closure method, and these data are limited currently.
The question of staples versus sutures for laparotomies has been studied with RCTs for CDC II and III cases [6–8]. Tsujinaka et al. [6] performed a multi-center RCT including 24 institutions and 1,072 patients who underwent an open gastrointestinal surgical procedure [6]. The rate of superficial SSIs was 6.4% for subcuticular sutures and 7% for staples (p = NS). In this study, they further broke this down by upper and lower gastrointestinal cases. While there remained no difference between closure methods in the upper gastrointestinal cases, there was a significant difference when it came to lower gastrointestinal cases (7.4% suture vs. 15.8% staples). This study also noted a higher rate of hypertrophic scar formation with staples, suggesting an improved cosmesis with subcuticular suture closure. It is notable that a more recent RCT of sutures vs. staples for colorectal cancer operations failed to show any difference between closure techniques; however, this trial included both laparoscopic and open procedures with laparoscopy comprising 80% of the cases [7].
An often cited reason for using staples rather than sutures in CDC II and III wound classes is that in the presence of a post-operative superficial SSI, staples allow you to open the wound without exposing the remainder of the wound to dehiscence. Anecdotally, this surgical dogma has not proven true, and this author closes all wounds regardless of CDC I, II, or III with running subcuticular sutures. The greater patient appreciation because of an improved cosmetic outcome and not necessitating staple removal in the office outweighs the additional time in the operating room needed to close with running subcuticular sutures.
Skin Closure Adjuncts
There have been many skin closure adjuncts employed to reduce surgical wound morbidity. Some are pre-closure, wound irrigation, and some are post-closure such as topical antibiotic agents and NPWT applied to a closed incision. All, however, remain debatable as to their efficacy despite having been studied in many surgical settings.
Intra-operative wound irrigation before laparotomy closure is one of the most studied questions within the surgical literature. This is highlighted by the systematic review and meta-analysis performed by Mueller et al. [9] in 2015. That rigorous analysis of the literature identified 41 RCTs with more than 9,000 combined patients studied to not only address the question of whether or not surgeons should irrigate wounds before closure, but also addressing what to irrigate with. Their analysis demonstrated a significant reduction in SSIs when wound irrigation was used (OR 0.54; 95% CI: 0.42–0.69). Subgroup analysis demonstrated that the impact of wound irrigation was greatest when used during colorectal cases and had less benefit for non-colorectal abdominal operations.
Additional subgroup analysis was performed to evaluate the use of antibiotic irrigation compared with povidone-iodine (PVP-I) solutions or saline alone. Antibiotic irrigation had a greater impact on SSI reduction than PVP-I with both outperforming saline alone. Within this discussion of wound irrigation, it should be mentioned that concerns over the negative wound healing effects of PVP-I and the impact of antibiotic irrigation on antibiotic stewardship are not necessarily addressed within a large meta-analysis such as this. Both concerns are legitimate and deciding whether these potentially adverse effects are outweighed by SSI reduction should be the focus of further investigations.
Topical antibiotic agents have been added to a variety of wounds closed by primary intention including lacerations closed in the emergency department, minor outpatient dermatologic procedures, as well as wounds closed in the operating room under sterile conditions. As vast as the spectrum of wounds that topical antibiotic agents are placed on is the variety of antibiotic agents or antibiotic combinations used as topical agents, thus limiting the generalizability of currently available studies in the literature.
Nevertheless, a recent Cochrane review by Heal et al. [10] addresses the question of topical antibiotic agents for preventing SSIs in wounds healing by primary intention. They found with 10 RCT that topical antibiotic agents probably do reduce SSIs and further indicate that topical antibiotic agents would reduce 20 SSIs per 1,000 patients. This result means that 50 patients would require treatment with topical antibiotic agents to reduce a single SSI. This review is limited in many ways, but maybe most importantly is that there is no indication as to the severity of the wound infections. As such, determining the value of treating 50 patients with topical antibiotic agents is extremely difficult because topical antibiotic agents may only be reducing minor SSIs that necessitate a limited wound opening with no need for systematic antibiotic agents. In addition, there is a percentage of patients who experience contact dermatitis with topical antibiotic agents. The Cochrane review by Heal et al. [10] was unable to come to any clear conclusions regarding contact dermatitis; however, some RCTs have indicated that risk of allergy induction may outweigh the benefits of topical antibiotic agents [11].
The most recent adjunct to wound closure is the addition of NPWT to a closed surgical incision. With this method, the NPWT device is applied directly on top of the closed wound. This can be performed with an all-in-one pre-packaged wound dressing or devised by placing a thin strip of non-adherent dressing over the incision with a similar width strip of vacuum sponge over the dressing. The occlusive dressing and vacuum device are applied as one would for an open wound. The NPWT is thought to reduce lateral tension, improve lymphatic clearance, and reduce hematomas and seromas [12].
There have been several trials investigating NPWT for high-risk wounds that are at increased risk of wound morbidity. A meta-analysis by Strugala and Martin [12] suggests that NPWT does significantly reduce SSIs; however, many of the studies have conflicts of interest and, as such, these studies should be considered in light of this. In addition, NPWT is the most costly of the described adjuncts, and, as a result, it must have a greater reduction in negative wound events to add value. The added value of this costly device has not been investigated in these studies and should be the emphasis of future studies.
Primary Closure Versus Delayed Primary Closure
Contaminated and dirty abdominal incisions present one of the greatest management challenges for surgeons. In the current state of healthcare, an SSI has such a negative connotation that at times it feels as though it is a “never event” despite ample literature defining SSI rates of up to 40% in CDC III and IV wounds. While this should not impact a surgeon's decision to manage such wounds either through primary closure, delayed primary closure, or via secondary intention, the reality is that this weights in the mind of a surgeon's subconscious.
He et al. [13] investigated the wound management of trauma laparotomies comparing primary closure with intermittent staples with wicks and to leaving the wound open. That study found an increased rate of surgical incision complications when the wound was left open while also suggesting that there was no increased risk of an SSI if the wound was closed via primary intention. In addition, patients with open wounds had longer hospital lengths of stay and took longer to heal their wounds. The authors concluded that closing CDC class III and IV wounds might be performed more safely than commonly perceived.
Delayed primary closure is an alternative to closure by secondary intention that reduces time to healing by closing wounds on postoperative day 3–5. This method of closure previously has been suggested to reduce SSIs [14,15]; however, a meta-analysis by Bhangu et al. [16], reviewing eight RCTs from 1992 to 2012, concluded that current trials fail to provide definitive evidence that delayed primary closure reduces SSIs when compared with the primary closure of contaminated and dirty abdominal wounds. In total, those eight RCTs included 623 patients, leading the authors to suggest that future RCTs addressing this question need to include larger numbers of patients.
A more recent RCT from 2018 evaluated primary closure versus delayed primary closure in 607 patients undergoing open appendectomy for complicated appendicitis [17]. Patients undergoing primary closure had a lower, but statistically insignificant, rate of superficial SSIs. Importantly, though, was the fact that managing these wounds with primary closure significantly reduced the cost required to care for these patients. This lower cost and no difference in SSIs suggests that primary closure of contaminated wounds adds more value than closing via delayed primary closure. Considering the currently available literature, surgeons should give serious consideration to primarily closing contaminated and dirty wounds; however, when electing for this method, careful wound monitoring is required.
Conclusion
The optimization of wound management to reduce SSIs begins with good surgical technique and patient optimization followed by careful fascial closure with the short stitch technique. All low-risk wounds should be closed with subcuticular suture and not adjuncts as they add little value for these surgical wounds. Surgeons should also give strong consideration to primarily closing contaminated wounds. While some studies have shown a reduction in SSIs with adjuncts such as wound irrigation, topical antibiotic agent, and NPWT the true added value of these needs additional investigation because they do impact cost, patient experience, and antibiotic stewardship.
Footnotes
Author Disclosure Statement
Dr. Krpata receives an educational grant from WL Gore and has received research consulting fees from Medtronic.