Discussion

When evaluating TAC techniques, WC had similar outcomes to ABTHERA in terms of ventilator days and time to definitive closure. However, duration of TAC placement was significantly shorter in the WC cohort. The differences in LOS and ICU LOS between the two groups were governed by trauma and injury-related confounding factors (eg, the number of laparotomies). Further, complications including bleeding, wound dehiscence, evisceration, and reoperation were comparable between WC and ABTHERA. Given similar outcomes and complication rates, this study demonstrates that WC is a reasonable option for TAC of the OA in appropriate trauma patients.

Similar to other published literature of OA in trauma, this is a relatively small series of patients. Although the study was conducted at a high-volume, high-acuity level I trauma center, with approximately 4000 admissions per year, only 112 patients were treated with OA in 6 years. This represents fewer than 1% of our patient population. The low utilization of OA reflects a consensus among our trauma team that damage control surgery, although lifesaving in certain situations, is not without its drawbacks. There is an increasing awareness in the global trauma community, reflected in recent literature, of the downsides of an OA, especially when maintained for a prolonged period.11

In recent years, several studies have established ABTHERA as the TAC method of choice, especially in the USA.3 5 12–15 Ease of use of a prepackaged device and uniformity of a commercially available device across institutions, which allows surgeons to perform the same procedure each time in the same way as their peers, are likely responsible for this popularity and rapid increase in use during the past decade. However, negative pressure dressing systems such as ABTHERA are not without their limitations, including the relatively high costs of commercial dressings compared with ‘home-made’ alternatives that use existing OR supplies.4

Only a handful of studies provide an evaluation of ABTHERA and WC, which is not surprising given that WC is a very old, basic surgical technique with no associated propriety or commercial interest, and investigators tend to focus on what is novel and innovative. Several systematic reviews have attempted to determine the optimal TAC technique, but results are limited due to their small sample size of WC patients.7 16–18 Other retrospective reviews have focused on negative pressure devices only, stating that skin-only closure techniques have largely been abandoned due to increased risks of evisceration, infection, and recurrent abdominal compartment syndrome.3 4 16

Several retrospective studies comparing WC closure against other methods such as Bogota bag, modified Barker’s vacuum packing, and ABTHERA6 19 have shown beneficial outcomes with WC. For instance, Patel et al19 found that LOS, number of explorations, time to closure, and ventilator days were significantly lower in patients undergoing skin closure than bridge (Bogota bag, artificial burr) vacuum-assisted devices. However, only 11% were trauma patients in their cohort of patients who underwent TAC. Similarly, Hu et al6 found that patients with skin-only closure had significantly higher rates of fascial closure and lower hospital mortality compared with patients receiving ABTHERA, Bogota bag, or a modified Barker’s vacuum pack for TAC. However, in their study, the cohort who underwent primary skin closure had a lower injury burden than the other TAC methods, which should be recognized when evaluating their results.

In contrast, both cohorts in the current study had comparable injury severity at presentation, with similar proportions of blunt and penetrating trauma, and a larger sample size than prior literature. Indications for the first OA in each group were similar, except there was a higher proportion of WC patients with diffuse bleeding that was packed, or with a poor prognosis who were not expected to live, suggesting a higher injury burden in these patients. Despite this, we found no difference in outcomes of WC to ABTHERA in terms of ventilator days, time until definitive closure, or death. Even though univariate analysis showed superior outcomes related to LOS and ICU LOS, these results were mediated by other trauma-related factors such as a larger number of laparotomies. When evaluating the results in this context, there was ultimately no difference in outcomes when evaluating the two methods, and the outcomes were comparable.

Regarding complications, although some studies showed no difference, other authors have reported worse outcomes with WC.3 4 16 Several prior studies note that WC has largely been abandoned due to the high risks of complications. These studies raise concern for evisceration, intra-abdominal hypertension, infection, and recurrent abdominal compartment syndrome, with rates reported from 13% to 36% with the use of WC.3 4 16 Although limited in sample size, Kruger et al20 report high complication rates in their cohort of patients undergoing emergent laparotomy and skin-only closure in South Africa. Of their 25 patients undergoing skin-only closure, 70% developed a postoperative complication, with 28% developing an SSI. The results from our current study vary significantly from these findings, although differences in country, clinical setting and practice, and injury mechanism may explain some of this variation. The current study findings of no adverse increase in complications with WC are supported by another recent study from Hu et al6 that showed no significant difference in complications when comparing WC with ABTHERA. Similarly, in our study, WC had a similar overall complication rate than ABTHERA when controlled for the duration of TAC application.

Due to the 12-hour shift-based model used at our institution, the surgeon performing the index operation was not necessarily the surgeon performing subsequent operations; thus, 26 patients received both closure methods during their stay. Regarding the patients who had both methods, most (65%) had WC first then ABTHERA. Surgeon preference largely drove the decision whether to use WC or ABTHERA. As such, certain surgeons, including the senior author (SD) primarily used WC, whereas others primarily used ABTHERA. Our findings indicate that the switch to ABTHERA happened later, an average of 3.3 days postoperatively, compared with the switch to WC, which occurred an average of 0.8 days postoperatively. Given the later transition from WC to ABTHERA, it is possible that the surgeon started with WC and transitioned to ABTHERA when they could not primary close, although this was not generally explicitly stated in the operative note. This introduces possible bias, which should be acknowledged when evaluating the results of the patients receiving both methods.

Although we did not conduct a formal cost analysis, the price difference between WC and ABTHERA warrants comment. Although prices vary at each hospital in the USA based on negotiated contracts, at the institution where this study was conducted, the nylon suture (usually size 0–2) on a cutting needle used for WC closure ranges from $1.71 to $3.91 a suture, and one to two sutures are used for each patient. In comparison, each ABTHERA dressing kit is $478.40, a cost that is repeated with each dressing change. Thus, there is a substantial cost savings to the patient and healthcare system associated with WC versus ABTHERA TAC placement.

Healthcare costs are a major concern throughout the world, especially in low-income to middle-income countries; therefore, the economic component is an important practical consideration when selecting the appropriate TAC method. Each year, 5.8 million people worldwide die from traumatic injuries, with 90% of deaths occurring in low-income to middle-income countries.21 Barriers driving these abysmal statistics include lack of access, availability, and affordability of surgical care, as well as limited resources necessary to provide appropriate care.22 23 Thus, low-cost surgical management strategies can make a major impact in limited resource settings. The implications of our findings of similar outcomes and complications of WC to ABTHERA in trauma patients requiring a period of OA management may benefit surgeons in resource-limited settings by providing the low-cost and readily available option of simple suture closure. As stewards of surgical and trauma care, it is important that surgeons participate in systemic decisions to ensure we use the limited resources at hand to benefit the greatest number of patients.

Limitations of this study include the design as a retrospective single-center study and the resulting small sample size, although this is still one of the largest to date evaluating WC patients. Ideally, the preliminary data generated by this study will form the basis of a prospective, multicenter collaborative trial that can provide more robust information on this critically injured patient population. Second, this was a convenience sample, with the decision for WC versus ABTHERA based on which surgeon was on call when the patient arrived, rather than a randomized controlled study, which would clearly have been preferable. Despite this, the two groups were well matched in trauma-specific clinical criteria at baseline, so it is doubtful this introduced much meaningful bias into the results. Since the decision was based on attending surgeon habitual preference, it is possible the difference in outcomes is due to the difference in clinical aptitude and practice between surgeons; however, as this study was conducted at an institution using a full shift-based ACS model, the surgeon doing the operation was not necessarily the surgeon providing all the subsequent ICU care and decision-making and may or may not have been the surgeon performing the next operation. Given that multiple surgeons were involved in each patient’s care, we would expect any individual surgeon effect to be significantly mitigated in the final results. Third, there were differences in patient groups who received a particular TAC, which precludes interpreting these findings as a head-to-head comparison. For instance, since the ability to perform WC is predicated on the ability to approximate skin, that alone excludes patients with massive visceral distention that may have prevented skin approximation. Similarly, patients who underwent decompressive laparotomy for abdominal compartment syndrome would not receive WC, whereas patients who were not expected to survive, and received TAC simply to be transferred out of the OR prior to inevitable demise, disproportionately received WC. Finally, since there were a few patients who required a complex, staged abdominal wall reconstruction using fascial traction techniques after a period of time on ABTHERA, this may have contributed to the longer time to fascial closure present in this group. The indications for TAC in the first OA are also subject to bias since they were extracted from the surgical operative note; however, due to the retrospective nature of the study, objective metrics were not available for this data point. Despite the limitations acknowledged, as a result of the findings of this study, the trauma team at our institution has switched almost entirely to WC of the OA where feasible in the trauma population, reserving ABTHERA only for cases where abdominal compartment syndrome has been diagnosed.

Given the multiple confounders inherent in any study performed in this critically ill and complex population with multiple injuries, it would be unreasonable to make sweeping generalizations regarding which is the better method based on retrospective data alone. Instead, we suggest these findings justify viewing WC as a viable TAC option, with similar outcomes and lower cost than commercially available alternatives, for patients in whom this method is feasible. Among the TAC options available for OA in critically ill trauma patients, WC is an effective and cost-efficient option. This should be considered in appropriate patients when determining the optimal technique for temporary closure of an OA.