Taming colonic anastomotic leakage: Wisdom from the ancient Chinese legend of Yu the Great

Abstract

Colonic anastomotic leakage (AL) remains the most severe complication of colorectal surgery, significantly increasing morbidity, mortality, and healthcare burdens. The ideal solution - complete AL prevention without a defunctioning stoma - has long eluded surgeons and patients. Hu et al proposed total enteric flow diversion using a modified ileostomy tube with an inflatable balloon, demonstrating its efficacy in completely preventing AL in porcine models. This innovation echoes the ancient legend of Yu the Great, a Chinese hero renowned for taming the Yellow River’s catastrophic floods. Unlike his father, who failed by merely building embankments to block water, Yu succeeded by dredging channels to redirect floods seaward. This paradigm of “diversion over obstruction” applies equally to AL prevention. Beyond Hu et al’s balloon technique, alternatives like the C-seal, the SafeHeal Colovac+ anastomosis protection device and Tong et al’s biodegradable stent-based diverting techniques show promise in clinical trials. Key challenges remain: Diversion efficiency, device migration risks, and patient tolerance. We must accelerate such like breakthroughs in non-stoma diversion strategies to transform AL management.

Key Words: Colonic anastomotic leakage; Diverting stoma; Intraluminal bypass device; Stent-based diverting technique; Yu the Great Tames the Flood

Core Tip: Yu the Great did not conquer water by building higher walls; he tamed it by carving new paths. Colonic anastomotic leakage prevention must likewise redirect, not exclude, intestinal flow. Despite promising results from devices that practice Yu’s diversion concept - including the C-seal, SafeHeal Colovac+, the biodegradable diverting stent, and water-inflatable balloons - accelerating breakthroughs in non-stoma strategies remains crucial to transforming anastomotic leakage management.

TO THE EDITOR

Anastomotic leakage (AL) is a feared complication following colorectal surgery, with reported incidence rates ranging from 2.8% to 30% despite advances in surgical techniques[1]. AL imposes a significant burden across the healthcare spectrum. For patients, it leads to severe morbidity; for clinicians, it demands complex management; and for healthcare systems, it triggers substantial costs due to additional interventions, extended hospitalizations, and higher readmission rates[2,3]. Consequently, extensive research has focused on pinpointing risk factors and refining preventive strategies to mitigate its impact[4,5]. Intraoperative measures to reduce AL risk now encompass techniques such as mechanical testing of the anastomosis, assessment of bowel perfusion with indocyanine green fluorescence imaging, strategic drain placement, and the creation of diverting stomas[6]. Defunctioning stoma (ileostomy/colostomy) is still the most common method used for AL prevention in clinical practice. While reducing AL severity, it introduces new complications: Dehydration, electrolyte imbalances, and impaired quality of life. Therefore, the ideal solution - complete AL prevention without a defunctioning stoma - has long eluded surgeons and patients[7].

In the recent issue, Hu et al[8] proposed total enteric flow diversion using a modified ileostomy tube with an inflatable balloon, demonstrating its efficacy in completely preventing AL in porcine models. They placed a balloon 10-20 cm proximal to the ileocecal valve, inflated it to 20 kPa pressure optimized intestinal occlusion without vascular compromise, and accomplished 100% AL prevention in the diversion group (vs 100% AL in controls). The methylene blue dye test was used to confirm a complete diversion, validating the “hydraulic seal” concept. Histology showed only mild mucosal injury at balloon contact sites. This approach eliminates stoma-related morbidity while enabling physiologic anastomotic healing.

Hu et al[8] ileostomy tube is somehow like the intrarectal catheters for fecal diversion in the management of perineal burns, such as ActiFlo Indwelling Bowel Catheter System (also known as the Zassi Bowel Management System, Hollister, IL, United States) and Flexi-Seal^® Protect Plus Fecal Management System (Convatec, NJ, United States)[9]. They all use a water-inflatable balloon to seal the enteric cavity and divert the enteric flow via the designed drainage channels.

These innovations echo the ancient legend of Yu the Great, a Chinese hero renowned for taming the Yellow River’s catastrophic floods[10]. Unlike his father, who failed by merely building embankments to block water, Yu succeeded by dredging channels to redirect floods seaward. This paradigm of “diversion over obstruction” applies equally to AL prevention.

Beyond Hu et al[8] balloon technique, alternatives like the C-seal, the SafeHeal Colovac+ anastomosis protection device and Tong et al’s biodegradable stent-based diverting techniques (SDTs) embodied Yu’s philosophy even earlier. The C-seal (Polyganics BV, Groningen, Netherlands) is an intraluminal soft sheath that is made of biodegradable polyurethane and degrades within approximately 2 weeks. The C-seal is compatible with a colorectal circular stapler. During the stapling process the C-seal is stapled to the afferent bowel loop proximal to the anastomosis. A pilot study was performed testing the C-seal in 15 patients diagnosed with colorectal carcinoma with stapled anastomoses in 2011, no radiologic or clinical ALs were observed after surgery[11]. However, in a subsequent multicenter randomized clinical trial (The C-seal trial, NTR3080) conducted in 41 hospitals in Europe, ALs leading to intervention occurred in 31 of 402 patients (7.7%): 21 of 202 patients (10.4%) in the C-seal group and 10 of 200 patients (5.0%) in the control group (P = 0.060)[12]. C-seal application in stapled colorectal anastomoses did not reduce AL, largely because the C-seal sheath was too soft, lacking the rigid circumferential support force to establish an effectively drainage channel[13].

The Colovac device offers a stoma-sparing approach for patients undergoing low anterior resection by functioning as a temporary intraluminal bypass. It is anchored proximal to the anastomosis via a stent and a vacuum mechanism, creating a protective sheath that lines the colon to the anus. This fully reversible device remains in situ for approximately 10 days, shielding the anastomosis during the critical healing phase. Its removal via endoscopy eliminates the need for a second surgical procedure, allowing patients to avoid the burdens of a stoma, enabling patients to resume their normal life without the stigma and complications associated with ostomy devices. Initial clinical results from the SAFE-1 trial (NCT05180565) completed in three European centers demonstrated 100% efficacy in protecting the anastomosis in all 15 enrolled patients, as evidenced by the absence of feces below the Colovac device[14]. Two multicenter randomized phase III trials (SAFE-2, NCT05010850 and SAFE-3CV, NCT07116668) are undergoing to assess the efficacy and the safety of the device in protecting low colorectal anastomoses created during oncological resection relative to standard diverting loop ileostomy[15].

As another alternative to ileostomy, Chinese surgeons Tong et al[16] pioneered a SDT. This system employs two key components: A solid, biodegradable intestinal stent placed 15-20 cm from the terminal ileum, and a mushroom-shaped tube positioned 5-10 cm proximal to it. While the stent physically blocks the passage of feces into the colon, the tube serves to redirect the intestinal contents. Crafted from Food and Drug Administration-approved materials, the stent gradually degrades into CO₂ and H₂O over three to four weeks. Following this degradation and the subsequent removal of the tube, intestinal flow is naturally restored to the colon, thereby obviating the need for a stoma reversal surgery. A prospective multicenter randomized clinical trial has been initiated, with preliminary findings indicating that SDT is a viable alternative to ileostomy for patients undergoing low anterior resection for rectal cancer.

Compared to a defunctioning stoma (ileostomy/colostomy), all diverting devices must meet three key challenges: Ensuring consistent diversion, minimizing device migration, and maintaining patient comfort (Table 1)[17]. Propose targeted solutions accordingly must actualize a rigid circumferential support force to establish an effectively drainage channel, a reliable fixation method to avoid the device migration, and a satisfactory degree of comfort during the device implantation in vivo and at the device removal. Hu et al’s study[8], while promising, is preliminary and requires validation in human trials. In the C-seal trial, 15.8% patients reported adverse events relating to the device application, including the C-seal detached from the anvil of the stapler, introduction of C-seal in afferent bowel loop difficult or impossible, difficulty in removal of stapler and double stapling of C-seal[12]. The SafeHeal Colovac+ device trial (SAFE-1) highlighted an effective diversion in 100% of cases, 92% patient acceptance tolerated vacuum tubes, and a migration rate to 13% due to dual-vacuum chamber optimization[14]. Tong et al’s SDT technique[16] reported a 97.3% diversion efficiency, 100% patient tolerance and no displacement of stents, though a 13.5% transient obstruction rate.

Table 1 Advantages and disadvantages of C-seal, Colovac and Tong et al’s stent-based diverting technique[16] vs the defunctioning stoma.

	Ensuring consistent diversion	Minimizing device migration	Maintaining patient comfort
Defunctioning stoma	Significant effects	N/A	No effect
C-seal	No effect	Moderate effects	Significant effects
Colovac	Moderate effects	Moderate effects	Moderate effects
Tong et al’s SDT[16]	Significant effects	Significant effects	Moderate effects

SDT: Stent-based diverting technique; N/A: Not applicable.

Yu’s flood control strategy - redirecting destructive forces rather than confronting them - finds resonance in modern AL prevention. Balloon catheters, intraluminal sheaths, and biodegradable stents exemplify this philosophy, offering stoma-free solutions with promising safety profiles. As Wu et al’s geological study corroborates[10], Yu’s legend was rooted in observable natural phenomena. Similarly, these innovations transform surgical dogma through evidence-based ingenuity. Channeling the future, we must accelerate more breakthroughs in non-stoma diversion strategies to transform AL management.