Esophagectomy remains the cornerstone of treatment for patients with early-stage and localized esophageal cancer, but it is associated with high morbidity and mortality. Anastomotic leakage is one of its most feared complications, with an incidence of 4.7%-41%, leading to increased complication rates, length of hospital stay, and even mortality. Especially after intrathoracic anastomosis, the occurrence of fistulas can lead to infectious mediastinitis, with potential adverse consequences. In order to reduce the anastomotic leakage rate, a variety of anastomotic techniques have been used, but the results are inconsistent because creating a perfect anastomosis remains challenging (difficult access and technique, and tissue ischemia may occur due to impaired ductal vascularization). Therefore, each esophageal surgeon begins his or her own exploration to determine the best anastomotic technique.
Circular staplers have been used for decades to facilitate improved integrity of intrathoracic anastomoses. Until recently, all circular staplers were manually actuated. Although they generally provide reliable tissue alignment, manual anastomosis can result in suboptimal tissue tension due to variable forces, muscle tension, and lateral motion during manual actuation. Therefore, powered stapler devices that use battery packs have been introduced, first with linear staplers and subsequently with circular staplers. Using a battery-powered stapler firing system, these devices compensate for variations in surgeon grip strength, potentially reducing motion of the distal stapler tip to allow for more stable anastomotic formation. These findings have been confirmed in ex vivo preclinical models. Furthermore, several retrospective studies comparing manual and powered circular staplers in colorectal surgery have demonstrated reduced fistula incidence. Therefore, the aim of our study was to objectively evaluate the effect of powered circular staplers on fistula incidence and complications following intrathoracic anastomosis in esophagectomy.
Compared with the manual circular stapler set, the design of the power circular stapler makes the staples more evenly distributed and the compression distributed during the firing process more evenly. Additionally, powered circular staplers are battery-operated to compensate for the manual grip force exerted during firing with a manual w-shaped stapler, which may result in reduced distal tip motion. Therefore, less tension is generated on the staples and anastomoses during the procedure. All of these factors may explain the reduced incidence of anastomotic leakage. The upcoming triple stapler technique with manual staplers is unlikely to change results compared with double-layer staplers, as Mazaki et al found no difference in fistula rates between the two techniques. Furthermore, anastomotic diameter is known to be a risk factor for anastomotic leakage; however, this has only been noted in cases of diameters of 31 mm and above. Several other studies of esophageal and colorectal cancer have shown no statistically significant differences between stapler sizes of 25-31 mm. Because only one patient in the dynamic group used a 31 mm stapler, this does not explain the difference in postoperative fistula development. In our opinion, the larger anastomotic diameter of the power group should increase its susceptibility to anastomotic dehiscence and therefore be a factor against the power group. Because, conversely, the incidence of anastomotic leakage was significantly reduced even in this case, which further supports our view that powered round-stomach firing provides a more uniform and solid anastomosis. Only after conducting randomized controlled trials can definite conclusions be drawn about both. However, it is most important to provide a stapler that is appropriately sized for the diameter of the esophagus. Oversize or undersize can lead to anastomotic deformation and make anastomotic dehiscence more likely.
Postoperative fistulas and complications are associated with increased mortality. Literature data shows that anastomotic leakage causes a 2-fold increase in the risk of pneumonia, a 10-fold increase in the risk of empyema, an increase in hospitalization time of more than 9 days, and accounts for 24.3% of readmission reasons. The 30-day mortality rate after anastomotic leakage is as high as 11%, resulting in reintervention in 80% of cases. In our propensity score matched cohort, we could observe the same results in terms of length of stay, with a significant difference of 7 days in the mean length of stay. There was no difference in mortality, as only one death was recorded in the manual round-nose group. Even in the unmatched cohort, there was a significant difference in the composite comorbidity index, which could not be confirmed in the matched cohort. We believe that this is due, at least in part, to the early detection of the fistula by imaging on postoperative day 4, which allowed for early supportive care with antibiotics, continuous drainage via a chest tube, and the use of intracavitary vacuum therapy in the case of a fistula. The success rate of intracavitary vacuum treatment is as high as 93%. It can be replaced 2-3 times a week and is suitable for various fistulas.
A significant reduction in anastomotic dehiscence was also observed after the introduction of powered circular staplers in left-sided colorectal resections, with both length of stay and readmission shortened by 30 days. Pollack et al calculated that assuming 100 resections per year (1.8% and 6.6%, respectively), surgical resection with a powered circular stapler resulted in an annual economic benefit of $53,987 (risk reduction 73%; P < 0.0001). This includes costs associated with anastomotic leaks, prolonged hospital stays, readmissions, and non-home discharges. Although cost reduction was not evaluated in our study, the 80% risk reduction was even higher in our study, implying greater economic benefit.
The strength of this trial is that both groups of patients were contemporary patients, so we could avoid comparisons with historical cohorts. Therefore, we do think that these results are very representative of the current daily situation. The trial was conducted in a high-volume academic center, and all participating surgeons had at least 5 years of experience and performed at least 20 operations per year. In addition, propensity score matching was performed to correct for potential confounders in a retrospective analysis of an unselected group of patients. In addition, all anastomotic procedures were performed in a standardized manner by all surgeons to avoid the introduction of other potential confounders other than the type of stapler. As mentioned earlier, techniques known to potentially reduce the risk of anastomotic leaks, such as reinforcing the anastomosis with a row of sutures to reduce tension on the stapler and wrapping the anastomosis with the greater omentum, were used in exactly the same way in both groups of patients. However, this study also has some weaknesses. The first one is the sample size. Although a total of 128 patients allowed for the distinction between the two surgical approaches. It was not sufficiently powered to detect small differences in postoperative complications. To detect these differences, comparative studies with larger sample sizes or future meta-analyses are needed. Second, despite propensity score matching and adjustment for preoperative confounders, the patient cohort studied was still a population of patients who underwent surgery via an open thoracoabdominal approach. Whether these results can be extrapolated to the formation of anastomoses in minimally invasive esophagectomy is unclear, although we believe that the potential advantages of the described powered stapler remain independent of the approach. Further clinical evidence is indeed needed to confirm this view.
Furthermore, there may be a selection bias, as the use of new devices could inadvertently affect the meticulousness with which the anastomosis is performed. On the other hand, surgeons were free to choose the stapler they preferred, but they trusted their choice. We did not observe major differences in the choice of instrument among surgeons. Moreover, at the end of the study, all surgeons started using powered circular staplers, confirming the preliminary results. Five months later, 23 consecutive patients underwent esophagectomy with left thoracoabdominal approach and intrathoracic anastomosis with powered anastomosis, with only one fistula (4.35%). However, further studies on anastomotic stenosis and quality of life are necessary to determine the long-term effects of powered circular staplers in upper gastrointestinal surgery. Anastomotic stenosis is thought to be associated with postoperative anastomotic fistula, but also with the size of the anastomosis, which is less common with hand-sewn anastomosis. Given the lower incidence of fistulas and a significantly higher median anastomotic diameter in the powered group, we believe that less stenosis is observed in the long term. Further follow-up data will have to confirm these hypotheses.