Clinical diagnostic advances in intestinal anastomotic techniques: Hand suturing, stapling, and compression devices

Abstract

The development of intestinal anastomosis techniques, including hand suturing, stapling, and compression anastomoses, has been a significant advancement in surgical practice. These methods aim to prevent leakage and minimize tissue fibrosis, which can lead to stricture formation. The healing process involves various phases: hemostasis and inflammation, proliferation, and remodeling. Mechanical staplers and sutures can cause inflammation and fibrosis due to the release of profibrotic chemokines. Compression anastomosis devices, including those made of nickel-titanium alloy, offer a minimally invasive option for various surgical challenges and have shown safety and efficacy. However, despite advancements, anastomotic techniques are evaluated based on leakage risk, with complications being a primary concern. Newer devices like Magnamosis use magnetic rings for compression anastomosis, demonstrating greater strength and patency compared to stapling. Magnetic technology is also being explored for other medical treatments. While there are promising results, particularly in animal models, the real-world application in humans is limited, and further research is needed to assess their safety and practicality.

Key Words: Anastomoses, Diagnostic advances, Anastomotic techniques, Technique, Intestine

Core Tip: The development of techniques for the creation of intestinal anastomoses, such as hand suturing, stapling, and compression anastomoses, represents a significant advancement in surgical practice. Compression anastomosis devices reduce inflammation compared to sutured anastomosis, and they yield leakage and stenosis rates similar to those of standard sutured and stapled colorectal anastomoses. Recent reports suggest that these devices facilitate the safe and efficient creation of intestinal anastomoses. For instance, compression anastomoses have exhibited a greater bursting strength and wider patency than stapled anastomoses, even after chemoradiotherapy. Nevertheless, the potential of compression anastomosis, including its safety and practicality, warrants further investigation.

INTRODUCTION

The development of techniques for the creation of intestinal anastomoses, such as hand suturing, stapling, and compression anastomoses, represents a substantial advancement in surgical practice. An ideal anastomotic connection must have sufficient strength to prevent leakage during peak tissue weakness and minimize tissue fibrosis, which could lead to stricture formation. A key prerequisite for optimal anastomosis is stress-free alignment of the wound edges, ensuring an adequate blood supply[1].

In principle, anastomosis has several stages: Hemostasis and inflammation (days 0-3), proliferation (days 4-14), and remodeling and scar maturation (from day 15 onward). Colorectal anastomoses are typically created using mechanical staplers or one or more suture layers[2]. This process can trigger an inflammatory response characterized by a foreign body granulomatous reaction at the anastomosis site, potentially leading to stricture formation due to the ongoing release of profibrotic chemokines, e.g., transforming growth factor-β and platelet-derived growth factor[3]. This issue has spurred numerous attempts to create “sutureless” bowel–bowel anastomoses[4].

The intestinal anastomotic healing process can be divided into the acute inflammatory, proliferative, and remodeling or maturation phases. As collagen is the most critical molecule in determining the strength of the intestinal wall, its metabolism is vital to our understanding of anastomotic healing[4].

Incorrectly performed anastomoses can lead to severe complications, such as peritonitis, sepsis, or death related to complications following gastrointestinal resection surgery[5]. Colorectal anastomotic leakage is a common postoperative complication, particularly after anterior resection of the rectum. The incidence of anastomotic leakage varies from 1% to 24%, with higher rates typically being observed in elective rectal anastomoses (12%-19%) than in colonic anastomoses (11%)[4]. Specifically, the leakage rates in ileocolic anastomoses are approximately 1%-4%, and those in colocolic anastomoses are 2%-3%. The risk of leakage is greater in complex surgeries than in simple surgeries, particularly in lower colorectal anastomoses, reaching 10%-14%[6].

A compression anastomosis device that can be used in a minimally invasive manner can address a wide range of surgical challenges, including malignant bowel obstruction, traumatic bowel injury, enterostomy closure, and congenital anomalies of the esophagus and intestines[7-9]. The concept of compression anastomosis, first introduced in 1826, has been explored and refined over time[10,11]. These devices, with recent developments based on nickel–titanium alloy rings that require no suture fixation, have been proven safe in elective and emergency settings[12]. As they leave no foreign bodies at the surgical site, they reduce inflammation compared with sutured anastomosis, and they yield similar leakage and stenosis rates to those of standard sutured and stapled colorectal anastomoses[13].

Despite advances in safety, anastomotic techniques are primarily evaluated on the basis of the risk of leakage. These techniques can be categorized according to their reproducibility, associated trauma, complexity, and usability. Flawless anastomotic healing is crucial for successful patient recovery. However, despite the use of various implants and methodologies, the risk of complications, such as anastomotic leakage (with rates of up to 10%) and stenosis, remains high. These complications are the leading causes of morbidity and mortality after visceral surgery.

Compression devices operate via a simultaneous process of pressure necrosis and repair at the anastomotic site. The entrapped bowel undergoes marked ischemia, tissue necrosis, and sloughing off of the inner, compressed tissue into the fecal stream while the outer bowel tissues heal. Recent reports have suggested that these devices facilitate the safe and efficient creation of intestinal anastomoses[14]. For instance, compression anastomoses have exhibited a greater bursting strength and wider patency than stapled anastomoses[15], even after chemoradiotherapy[16].

Magnamosis, comprising two self-assembling magnetic rings, represents a major advancement in endoscopically compatible systems for full-thickness compression anastomoses of the bowels. The device design includes convex-concave, radially symmetric halves that self-align magnetically and ring-shaped magnetic halves for immediate patency. The mating surfaces have a specially engineered radial topography to promote gradual remodeling and healing of compressed intestinal walls[17].

The use of enteric magnets for anastomosis was first described in animal models and then later in humans. Magnetic technology is increasingly used in the medical field for various treatments, including vascular anastomoses[18,19] and the treatment of gastrointestinal diseases.

In human trials, the use of flat magnetic rings for mucosa-to-mucosa anastomosis has been explored, with patency occurring after 7-12 d[20]. However, two cases of anastomotic leaks were reported during the follow-up of 21 patients[21]. Magnacystostomy has also been proposed as a minimally invasive technique for suprapubic cystostomy, particularly when typical methods are contraindicated. Magnetic treatment for short urethral strictures is effective in children[22].

In animal models, magnamoses (gastrojejunostomy and jejunojejunostomy) develop strengths comparable to or greater than those of hand-sewn or stapled anastomoses. The advantages of these devices include ease of insertion, coupling, and removal as well as their less invasive nature compared with other devices. However, the time required for anastomotic completion can vary among organs, and this technique may not be suitable for patients who require immediate decompression[23].

Although the system has been used to create side-to-side colorectal anastomoses, failures due to magnetic-ring detachment have been reported. Additionally, mild-to-moderate stenoses were observed in some cases, although these decreased in severity over time[24].

CONCLUSION

Despite their theoretical benefits, the utility of these compression devices in clinical settings remains limited. Real-time monitoring of the healing process is often not feasible, leading to a reliance on traditional or slightly more advanced methods. However, magnetic anastomosis is not just confined to clinical trials; it is already being employed in clinical practice, notably in cases of long gap esophageal atresia and cholangiojejunostomy[25]. We also expect its scope of use to expand to the treatment of fistulas in the pancreatobiliary area. Nevertheless, the potential of compression anastomosis in certain scenarios warrants further investigation regarding its safety and practicality.