Compression anastomoses in colorectal surgery: a review

Development of implantable electrode based on bioresorbable Mg alloy for tissue welding application

An implantable electrode based on bioresorbable Mg-Nd-Zn-Zr alloy was developed for next-generation radiofrequency (RF) tissue welding application, aiming to reduce thermal damage and enhance anastomotic strength. The Mg alloy electrode was designed with different structural features of cylindrical surface (CS) and continuous long ring (LR) in the welding area, and the electrothermal simulations were studied by finite element analysis (FEA). Meanwhile, the temperature variation during tissue welding was monitored and the anastomotic strength of welded tissue was assessed by measuring the avulsion force and burst pressure. FEA results showed that the mean temperature in the welding area and the proportion of necrotic tissue were significantly reduced when applying an alternating current of 110 V for 10 s to the LR electrode. In the experiment of tissue welding ex vivo, the maximum and mean temperatures of tissues welded by the LR electrode were also significantly reduced and the anastomotic strength of welded tissue could be obviously improved. Overall, an ideal welding temperature and anastomotic strength which meet the clinical requirement can be obtained after applying the LR electrode, suggesting that Mg-Nd-Zn-Zr alloy with optimal structure design shows great potential to develop implantable electrode for next-generation RF tissue welding application.

Mechanobiological considerations in colorectal stapling: Implications for technology development

Technological advancements in minimally invasive surgery have led to significant improvements in patient outcomes. One such technology is surgical stapling, which has evolved into a key component of many operating rooms by facilitating ease and efficacy in resection and repair of diseased or otherwise compromised tissue. Despite such advancements, adverse post-operative outcomes such as anastomotic leak remain a persistent problem in surgical stapling and its correlates (i.e., hand-sewing), most notably in low colorectal or coloanal procedures. Many factors may drive anastomotic leaks, including tissue perfusion, microbiome composition, and patient factors such as pre-existing disease. Surgical intervention induces complex acute and chronic changes to the mechanical environment of the tissue; however, roles of mechanical forces in post-operative healing remain poorly characterized. It is well known that cells sense and respond to their local mechanical environment and that dysfunction of this "mechanosensing" phenomenon contributes to a myriad of diseases. Mechanosensing has been investigated in wound healing contexts such as dermal incisional and excisional wounds and development of pressure ulcers; however, reports investigating roles of mechanical forces in adverse post-operative gastrointestinal wound healing are lacking. To understand this relationship well, it is critical to understand: 1) the intraoperative material responses of tissue to surgical intervention, and 2) the post-operative mechanobiological response of the tissue to surgically imposed forces. In this review, we summarize the state of the field in each of these contexts while highlighting areas of opportunity for discovery and innovation which can positively impact patient outcomes in minimally invasive surgery.

Transanal formation of anastomosis using C-REX device is feasible and effective in high anterior resection

PURPOSE

C-REX is a novel instrument for creating stapleless colorectal anastomosis by compression. The aim of this study was to evaluate the feasibility and effectiveness of C-REX in open and laparoscopic high anterior resections.

METHODS

A prospective clinical safety study on 21 patients reconstructed with C-REX colorectal anastomosis following high anterior resection of the sigmoid colon using two different devices for intraabdominal (n = 6) or transanal (n = 15) placement of the anastomotic rings. Any signs of complications were prospectively monitored by a predefined protocol. Anastomotic contact pressure (ACP) was measured via a catheter-based system, and time for evacuation of the anastomotic rings by the natural route was noted. Blood samples were collected daily, and flexible endoscopy was performed postoperatively to examine macroscopic appearance of the anastomoses.

RESULTS

One of six patients operated with the intraabdominal anastomosis technique with an ACP of 50 mBar had to be reoperated because of anastomotic leakage. None of the 15 patients operated with the transanal technique (5 open and 10 laparoscopic procedures) had anastomotic complications, and their ACP ranged between 145 and 300 mBar. C-REX rings were uneventfully expelled by the natural route in all patients after a median of 10 days. Flexible endoscopy showed well-healed anastomoses without stenosis in 17 patients and a moderate subclinical stricture in one patient.

CONCLUSION

These results indicate that the novel transanal C-REX device is a feasible and effective method for colorectal anastomosis following high anterior resections, irrespective of open or laparoscopic approach. Moreover, C-REX allows measurement of intraoperative ACP and thereby a quantitative evaluation of the anastomotic integrity.

Minimizing thermal damage using self-cooling jaws for radiofrequency intestinal tissue fusion

INTRODUCTION

Radiofrequency (RF)-induced tissue fusion shows great potential in sealing intestinal tissue without foreign materials. To improve the performance of RF-induced tissue fusion, a novel self-cooling jaw has been designed to minimize thermal damage during the fusion.

MATERIAL AND METHODS

The prototype of self-cooling jaws was developed and manufactured. A total number of 60 mucosa-to-mucosa fusions were conducted using ex-vivo porcine intestinal segments with the proposed design and conventional bipolar jaws. The effects of intestinal fusion were evaluated based on temperature curves, burst pressure, thermal damage, and histological appearances.

RESULTS

The self-cooling jaws showed significant decrease in temperature during the fusion process. An optimal burst pressure (5.7 ± 0.5 kPa) and thermal damage range (0.9 ± 0.1 mm) were observed when the applied RF power was 100 W. The thermal damage range of the prototype has almost decreased 36% in comparison with the conventional bipolar jaws (1.4 ± 0.1 mm). The histological observation revealed that a decrease of thermal damage was achieved through the application of self-cooling jaws.

CONCLUSIONS

The self-cooling jaws were proved to be effective for reducing the thermal damage during RF-induced tissue fusion, which could potentially promote the clinical application of tissue fusion techniques in the future.

Biodegradable shape memory alloys: Progress and prospects

Shape memory alloys (SMAs) have a wide range of potential novel medical applications due to their superelastic properties and ability to restore and retain a 'memorised' shape. However, most SMAs are permanent and do not degrade in the body when used in implantable devices. The use of non-degrading metals may lead to the requirement for secondary removal surgery and this in turn may introduce both short and long-term health risks, or additional waste disposal requirements. Biodegradable SMAs can effectively eliminate these issues by gradually degrading inside the human body while providing the necessary support for healing purposes, therefore significantly alleviating patient discomfort and improving healing efficiency. This paper reviews the current progress in biodegradable SMAs from the perspective of biodegradability, mechanical properties, and biocompatibility. By providing insights into the status of SMAs and biodegradation mechanisms, the prospects for Mg- and Fe-based biodegradable SMAs to advance biodegradable SMA-based medical devices are explored. Finally, the remaining challenges and potential solutions in the biodegradable SMAs area are discussed, providing suggestions and research frameworks for future studies on this topic.

Review of Colonic Anastomotic Leakage and Prevention Methods

Although surgeries involving anastomosis are relatively common, anastomotic leakages are potentially deadly complications of colorectal surgeries due to increased risk of morbidity and mortality. As a result of the potentially fatal effects of anastomotic leakages, a myriad of techniques and treatments have been developed to treat these unfortunate cases. In order to better understand the steps taken to treat this complication, we have created a composite review involving some of the current and best treatments for colonic anastomotic leakage that are available. The aim of this article is to present a background review of colonic anastomotic leakage, as well as current strategies to prevent and treat this condition, for a broader audience, including scientist, engineers, and especially biomedical engineers.

Preliminary study of a control algorithm for radio-frequency-induced intestinal tissue fusion

Purpose: A control algorithm for radio-frequency-induced intestinal tissue fusion was developed to explore the effects of different control parameters on intestinal tissue fusion.Materials and methods: Radio-frequency-induced fusion was performed on ex vivo small intestine tissue. The effect on the fusion was observed by changing the control parameters (power, interval time, and terminal impedance) in the algorithm. The quality of fusion was evaluated using the burst pressure and thermal damage measurement. Histological evaluation was used to assess the fusion quality indirectly.Results: A maximum burst pressure of 8.460 ± 0.2674 KPa was acquired when the power was set to 100 W, the interval time was set to 2000 ms, and the terminal impedance was set to 50 Ω. Moreover, the thermal damage range increased with an increase in power but decreased with an increase in the interval time and terminal impedance. Furthermore, the thermal damage range and temperature were presumably related.Conclusions: For an ex vivo small intestine tissue, the appropriate control parameters could be set when the power was approximately 100 W, the interval time was approximately 2000 ms, and the terminal impedance was approximately 50 Ω. This study could provide a basis for the selection of control parameters for intestinal tissue fusion.

Preventive strategies for anastomotic leakage after colorectal resections: A review

Anastomosis is a crucial step in radical cancer surgery. Despite being a daily practice in gastrointestinal surgery, anastomotic leakage (AL) stands as a frequent postoperative complication. Because of increased morbidity, mortality, combined with longer hospital stay, the rate of re-intervention, and poor oncological outcomes, AL is considered the most feared and life-threatening complication after colorectal resections. Furthermore, poor functional outcomes with a higher rate of a permeant stoma in 56% of patients this could negatively affect the patient’s quality of life. This a narrative review which will cover intraoperative anastomotic integrity assessment and preventive measures in order to reduce AL. Although the most important prerequisites for the creation of anastomosis is well-perfused and tension-free anastomosis, surgeons have proposed several preventive measures, which were assumed to reduce the incidence of AL, including antibiotic prophylaxis, intraoperative air leak test, omental pedicle flap, defunctioning stoma, pelvic drain insertion, stapled anastomosis, and general surgical technique. However, lack of clear evidence of which preventive measures is superior over the other combined with the fact that the decision remains based on the surgeon’s choice. Despite the advances in surgical techniques, AL remains a serious health problem associated with increased morbidity, mortality with additional cost. Many preventative measures were employed with no clear evidence supporting the superiority of stapled anastomosis over hand-Sewn anastomosis, coating of the anastomosis, or pelvic drain. Defunctioning stoma, when justified it could decrease the leakage-related complications and the incidence of reoperation. MBP combined with oral antibiotics still recommended.

Which Is the Safer Anastomotic Method for Colon Surgery? - Ten-year Results

BACKGROUND/AIM

In colon surgery, the anastomotic method is generally selected by surgeon's preferences or by local conditions. In this study, we retrospectively analyzed anastomotic complications to assess safe methods of anastomosis in colonic resection.

PATIENTS AND METHODS

We retrospectively analyzed a total of 684 cases, performed between July 2003 and June 2013 in our Hospital. Anastomosis complications, such as leakage, stricture and bleeding, were analyzed in relation to the three methods of anastomosis, hand-sewn (HS), functional end-to-end (FEEA) and triangulating anastomosis (TRI).

RESULTS

Univariate analysis indicated that the incidence of leakage was significantly lower in laparoscopic surgeries (p=0.034) and TRI (p=0.047). The results of the multivariable analysis indicated that anastomotic leakage was significantly less with TRI (p=0.029).

CONCLUSION

In colon surgery, TRI seems to be associated with a low risk of anastomotic leakage compared to HS and FEEA.

Experimental Procedure of Compression Anastomosis Using Fragmented Rings: A Porcine Model

BACKGROUND

Compression anastomosis has been recently abandoned because of a nonsuperiority compared to stapling anastomosis. Nonremoval of the rings has frequently been reported and this technique does not support a routine use. The aim of this experimental study was to assess the feasibility of anastomosis using compression with a device consisting of fragmented rings.

METHODS

A new compression device, the "Anastocom," was compared to standard double-stapled colocolonic anastomosis in 2 groups of 8 pigs. In each group, colocolonic anastomosis was performed with a circular stapler (DST Series EEA Staplers) in 4 pigs and with the Anastocom device for the other 4 pigs.

RESULTS

The anastomotic rings were expelled between postoperative day 7 and day 13 from the 4 animals sacrificed at day 30. The anastomosis was clean and intact in all pigs. After sacrifice, there was no difference in the bursting pressure at day 7 ( P = .226) or at day 30 ( P = .885) between the 2 types of anastomosis. After sacrifice at day 7, the mean bursting pressure values for the Anastocom and EEA anastomoses were 128.6 mm Hg (range 119-143 mm Hg) and 218.9 mm Hg (range 84-240 mm Hg), respectively. After sacrifice at day 30, the mean bursting pressure values for the Anastocom and EEA anastomoses were 111 mm Hg (range 59-234 mm Hg) and 105 mm Hg (range 81-130 mmHg), respectively.

CONCLUSION

No bowel obstruction was observed with Anastocom. This fragmentation mechanism should better prevent nonexpulsion compared to basic compression anastomosis.

A systematic analysis of controlled clinical trials using the NiTi CAR™ compression ring in colorectal anastomoses

Anastomotic leak following colorectal surgery can be a devastating adverse event. The ideal stapling device should be capable of rapid creation of an anastomosis with serosal apposition without the persistence of a foreign body or a foreign body reaction which potentially contribute to early anastomotic dehiscence or late anastomotic stricture. A systematic review was performed examining available data on controlled randomized and non-randomized trials assessing the NiTi compression anastomosis ring-(NiTi CAR™) (NiTi Solutions, Netanyah Israel) in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) standards. A protocol for this meta-analysis has been registered on PROSPERO (CRD42016050934). The initial search yielded 45 potentially relevant articles. After screening titles and abstracts for relevance and assessment for eligibility, 39 of these articles were eventually excluded leaving 6 studies for analysis in the review. Regarding the primary outcome measure, the overall anastomotic leak rate was 2.2% (5/230) in the compression anastomosis group compared with 3% (10/335) in the conventional anastomosis group; this difference was not statistically significant (RR 0.75, 95% CI 0.25-2.24; participants = 565; studies = 6; I ² = 0%). There were no statistically significant differences between compression and conventional anastomoses in any of the secondary outcomes. This review was unable to demonstrate any statistically significant differences in favor of the compression anastomosis technique over conventional manual or stapled mechanical anastomoses.

Gastrointestinal tract anastomoses with the biofragmentable anastomosis ring: is it still a valid technique for bowel anastomosis? Analysis of 203 cases and review of the literature

PURPOSE

Biofragmentable anastomosis ring (BAR) is an alternative to manual and stapled anastomoses performed within the upper and lower gastrointestinal (GI) tract. The aim of this study was to evaluate the effectiveness of BAR utility for bowel anastomoses based on our own material.

METHODS

A retrospective analysis was performed to a total of 203 patients who underwent bowel surgery with the use of BAR anastomosis within upper and lower gastrointestinal tract between 2004 and 2014. Data for the analysis was collected based on medical records, treatment protocols, and the results of histological examinations.

RESULTS

The study group consisted of 86 women and 117 men. The most common underlying pathology was a malignant disease (n = 165). Biofragmentable anastomosis ring (BAR) size 31 was the most commonly used (n = 87). A total of 169 colocolic or colorectal anastomoses and 28 ileocolic and 8 enteroenteric anastomoses were performed. The mortality rate was 0.5 % (n = 1) whereas re-surgery rate within 30 days was 8.4 % (n = 17). Twenty-eight patients developed perioperative complications with surgical site infection as the most common one (n = 11). Eight patients developed specific complications associated with BAR including an anastomotic leak (n = 6) and intestinal obstruction (n = 2). The mean time of hospital stay after surgery was 12.7 days.

CONCLUSIONS

The use of BAR for the GI tract anastomoses is simple and rapid method and it is characterized with an acceptable number of perioperative mortality and complication rates. Based on our experience, we recommend the use of BAR anastomosis in different types of intestinal anastomosis in varying clinical scenarios.

Compression versus hand-sewn and stapled anastomosis in colorectal surgery: a systematic review and meta-analysis of randomized controlled trials

Anastomotic leaks are a feared complication of colorectal resections and novel techniques that have the potential to decrease them are still sought. This study aimed to compare the anastomotic leak rates in patients undergoing compression anastomoses versus hand-sewn or stapled anastomoses. Randomized controlled trials (RCTs) comparing outcomes of compression versus conventional (hand-sewn and stapled) colorectal anastomosis were collected from MEDLINE, Embase and the Cochrane Library. The quality of the RCTs and the potential risk of bias were assessed. Pooled odds ratios (OR) were calculated for categorical outcomes and weighted mean differences for continuous data. Ten RCTs were included, comprising 1969 patients (752 sutured, 225 stapled, and 992 compression anastomoses). Most used the biofragmentable anastomotic ring. There was no significant difference between the two groups in terms of anastomotic leak rates (OR 0.80, 95 % confidence interval (CI) 0.47, 1.37; p = 0.42), stricture (OR 0.54: 95 % CI 0.18, 1.64; p = 0.28) or mortality (OR 0.70; 95 % CI 0.39, 1.26; p = 0.24). Compression anastomosis was associated with an earlier return of bowel function: 1.02 (95 % CI 1.37, 0.66) days earlier (p < 0.001) and a shorter postoperative stay; 1.13 (95 % CI 1.52, 0.74) days shorter (p < 0.001), but significant heterogeneity among studies was observed. There was an increased risk of postoperative bowel obstruction in the compression group (OR 1.87; 95 % CI 1.07, 3.26; p = 0.03). There was no significant difference in wound-related and general complications, or length of surgery. Compression devices do not appear to provide an advantage over conventional techniques in fashioning colorectal anastomoses and are associated with an increased risk of bowel obstruction.

Can a nickel-titanium memory-shape device serve as a substitute for the stapler in gastrointestinal anastomosis? A systematic review and meta-analysis

BACKGROUND

Recently, a nickel-titanium (NiTi) memory-shape device has been successfully used in gastrointestinal anastomosis. The aim of this study was to investigate the feasibility and safety of the device.

METHODS

Four databases, reference lists, and the World Health Organization International Clinical Trials Registry Platform were systematically searched for randomized controlled trials assessing the clinical efficacy of a NiTi memory-shape device compared with that of a stapler in gastrointestinal or colorectal anastomosis.

RESULTS

Seven randomized controlled trials regarding the use of compression anastomosis clips (CACs) were enrolled for meta-analysis. The use of CACs was associated with a significant reduction in hospital duration (mean = -0.88 d; 95% confidence interval [CI], -1.38 to -0.38), the time to flatus (mean = -0.36 d; 95% CI, -0.08 to -0.04), and the start of oral intake (mean = -0.45 d; 95% CI, -0.83 to -0.06), as well as a nonsignificant change in postoperative complications and mortality. These clinical outcomes did not significantly change with the use of compression anastomosis rings.

CONCLUSIONS

Colonic anastomosis with a CAC is likely to reduce hospital duration, time to flatus, and the start of oral intake without influencing mortality or postoperative complications and may be a safe and preferable choice in colonic anastomosis. Further well-designed trials should be performed to determine the safety and efficacy of the newly developed compression anastomosis ring in both ileocolic and colorectal anastomosis.

Long term results of the use of compression anastomosis clips (CAC) in gastrointestinal surgery – the first report

The aim of the study was to present the first long-term results on the clinical use of compression anastomosis clips (CAC) in upper and lower gastrointestinal tract anastomoses.

MATERIAL AND METHODS

The study included 50 patients who underwent anastomosis of the upper (n = 32) or lower GI tract (n = 18) with the use of CAC. In the period of 6-7 months after the surgery, patients underwent endoscopic examination and computed tomography evaluation of the anastomosis. Each anastomosis was evaluated macro and microscopically. The width of anastomoses was evaluated using a 4-point-scale for grading stenosis.

RESULTS

Of the 50 patients who underwent anastomosis with compression anastomosis clip, 28 (56%) patients reported to the follow-up examination within 190-209 days of the execution of the anastomosis. Among the 22 patients who did not report to the study, 18 (36%) patients died within 91-154 days from the execution of the anastomosis (mean 122 days), 4 (8%) patients were impossible to contact after discharge from hospital. Two mild stenoses (I0) were diagnosed; 1 of them was found in the gastroenterostomy and 1 in Braun enteroenterostomy. Microscopic changes were diagnosed in 4 anastomoses (3 gastroenterostomies, 1 Braun enteroenterostomy). Anastomoses were well-formed and wide, scars in the line of anastomoses were thin.

CONCLUSIONS

During the period of 6 months after the anastomoses performed using CAC have been formed, they were evaluated as unobstructed and functioning properly; therefore, they can be safely performed within the upper and lower gastrointestinal tract.

Compression anastomotic ring-locking procedure (CARP) is a safe and effective method for intestinal anastomoses following left-sided colonic resection

BACKGROUND

Compression anastomotic ring-locking procedure (CARP) is a novel procedure for creating colonic anastomoses. The surgical procedure allows perioperative quantification of the compression pressure between the intestinal ends within the anastomosis and postoperative monitoring of the anastomotic integrity. We have recently shown that CARP is a safe and effective method for colonic anastomoses in pigs, and the purpose of the present study was to evaluate CARP for colonic anastomoses in humans.

MATERIALS AND METHODS

This is a prospective study on 25 patients undergoing elective left-sided colonic resection. Time for evacuation of the anastomotic rings, perioperative compression pressure, and adverse effects were recorded. Postoperative blood samples were collected daily, and flexible sigmoidoscopy was performed 8-12 weeks after surgery to examine the anastomoses.

RESULTS

Fourteen out of 25 patients underwent CARP. CARP was not used in 11 patients due to advanced tumor disease (two cases) and size restrictions (nine cases). No case of anastomotic leakage, bowel obstruction, or stenosis formation was observed. No device-related perioperative adverse events were noted. The surgical device evacuated spontaneously in all patients by the natural route after a median of 10 days. Perioperative compression pressure ranged between 85 and 280 mBar (median 130 mBar). Flexible sigmoidoscopy revealed smooth anastomoses without signs of pathological inflammation or stenosis in all cases.

CONCLUSION

Our results indicate that the novel suture-less CARP is a safe and effective method for creating colonic anastomoses. Further studies are warranted in larger patient populations to compare CARP head-on-head with stapled and/or hand-sewn colonic anastomoses.

COMPRES: a prospective postmarketing evaluation of the compression anastomosis ring CAR 27(™) /ColonRing(™)

AIM

Preclinical studies have suggested that nitinol-based compression anastomosis might be a viable solution to anastomotic leak following low anterior resection. A prospective multicentre open label study was therefore designed to evaluate the performance of the ColonRing(™) in (low) colorectal anastomosis.

METHOD

The primary outcome measure was anastomotic leakage. Patients were recruited at 13 different colorectal surgical units in Europe, the United States and Israel. Institutional review board approval was obtained.

RESULTS

Between 21 March 2010 and 3 August 2011, 266 patients completed the study protocol. The overall anastomotic leakage rate was 5.3% for all anastomoses, including a rate of 3.1% for low anastomoses. Septic anastomotic complications occurred in 8.3% of all anastomoses and 8.2% of low anastomoses.

CONCLUSION

Nitinol compression anastomosis is safe, effective and easy to use and may offer an advantage for low colorectal anastomosis. A prospective randomized trial comparing ColonRing(™) with conventional stapling is needed.

Systematic review of preoperative, intraoperative and postoperative risk factors for colorectal anastomotic leaks

BACKGROUND

Anastomotic leak (AL) represents a dreaded complication following colorectal surgery, with a prevalence of 1-19 per cent. There remains a lack of consensus regarding factors that may predispose to AL and the relative risks associated with them. The objective was to perform a systematic review of the literature, focusing on the role of preoperative, intraoperative and postoperative factors in the development of colorectal ALs.

METHODS

A systematic review was performed to identify adjustable and non-adjustable preoperative, intraoperative and postoperative factors in the pathogenesis of AL. Additionally, a severity grading system was proposed to guide treatment.

RESULTS

Of 1707 papers screened, 451 fulfilled the criteria for inclusion in the review. Significant preoperative risk factors were: male sex, American Society of Anesthesiologists fitness grade above II, renal disease, co-morbidity and history of radiotherapy. Tumour-related factors were: distal site, size larger than 3 cm, advanced stage, emergency surgery and metastatic disease. Adjustable risk factors were: smoking, obesity, poor nutrition, alcohol excess, immunosuppressants and bevacizumab. Intraoperative risk factors were: blood loss/transfusion and duration of surgery more than 4 h. Stomas lessen the consequences but not the prevalence of AL. In the postoperative period, CT is the most commonly used imaging tool, with or without rectal contrast, and a C-reactive protein level exceeding 150 mg/l on day 3-5 is the most sensitive biochemical marker. A five-level classification system for AL severity and appropriate management is presented.

CONCLUSION

Specific risk factors and their potential correction or indications for stoma were identified. An AL severity score is proposed to aid clinical decision-making.

The compression anastomotic ring-locking procedure: a novel technique for creating a sutureless colonic anastomosis

BACKGROUND/AIM

Compression anastomoses might represent an improvement over traditional hand-sewn or stapled techniques. Herein, we describe a novel concept of sutureless colonic anastomosis named compression anastomotic ring-locking procedure (CARP).

MATERIALS AND METHODS

The surgical device consists of two anastomotic rings and their associated helping tools, facilitating the placement of the rings into the intestinal ends. Furthermore, four catheters are connected to the surgical device, allowing the evaluation of the anastomosis during and after surgery. A total of 31 pigs underwent a low colocolic anastomosis using the anastomotic rings. The compression pressure was measured perioperatively and up to 96 h after surgery. Anastomotic integrity and morphology were analyzed by use of radiology and histology, respectively. A long-term follow-up was conducted in a subgroup of pigs up to 108 days after surgery when the bursting pressure and stricture formation were examined.

RESULTS

All animals recovered uneventfully, and macroscopic examination revealed intact anastomoses without signs of pathological inflammation or adhesions. The perioperative compression pressure was inversely proportional to the gap size between the anastomotic rings. For example, an anastomotic gap of 1.5 mm created a colonic anastomosis with a perioperative compression pressure of 91 mbar, which remained constant for up to 48 h and resulted in a markedly increased compression pressure. Contrast infusion via the catheters effectively visualized the anastomoses, and no leakage was detected within the study. The surgical device was spontaneously evacuated from the intestines within 6 days after surgery. Histology showed collagen bridging of the anastomoses already 72 h after surgery. Long-term follow-up (54-108 days) revealed no stricture formation in the anastomoses, and the bursting pressure ranged from 120 to 235 mbar. The majority of bursts (10/12) occurred distant from the anastomoses.

CONCLUSION

We conclude that the surgical device associated to CARP is safe and efficient for creating colonic anastomoses. Further studies in patients undergoing colorectal surgery are warranted.

Diagnosis, management and outcome of early anastomotic leakage following colorectal anastomosis using a compression device: is it different?

AIM

Compression anastomosis has proved to be safe for rectal reconstruction with leak rates comparable to those observed using circular stapling devices. However, there are no data on whether the metallic compression ring alters the ease of diagnosis or the treatment in cases of leakage. In this study, we present our experience with early leakage following compression anastomosis.

METHOD

A prospective registry was used for data review. Patients with anastomotic leakage following compression anastomosis between November 2008 and September 2013 were included.

RESULTS

In all, 197 (92 female) patients were operated using a novel compression device. Early leakage was found in 10 (5.1%) patients after a median of 5 (3-14) days. The radiologist was able to detect leakage using CT in nine out of 10 cases unequivocally. Removal of the ring was necessary in eight of the 10 cases, and salvage of the anastomosis was feasible on six occasions. In all diverted cases with a low anastomosis, a transanal repair of the defect was feasible in three cases, including a single patient with complete separation of the anastomosis.

CONCLUSION

Artefacts on the CT scan caused by the compression ring did not hamper the diagnosis of anastomotic leakage. Removal of the ring in the early postoperative period is not associated with complete separation of the bowel ends. Salvage of anastomosis is feasible in most cases.

Ileocolonic anastomosis after right hemicolectomy for colon cancer: functional end-to-end or end-to-side?

Background

The purpose of this study was to compare short-term clinical outcomes of ileocolonic functional end-to-end anastomosis (FEEA) and end-to-side anastomosis (ESA) following resection of the right colon for cancer.

Methods

We enrolled 379 patients who underwent ileocolonic anastomosis following resection of the right colon for cancer by a single surgeon, from January 2009 through June 2012. Patient characteristics, operative results, and postoperative complications were analyzed.

Results

A total of 164 patients received ESA and 215 patients received FEEA. The FEEA group had a lower incidence of anastomotic error (0.9% versus 4.3%; P = 0.04) and a shorter operating time (140.4 ± 14.9 min versus 150.5 ± 20.1 min; P = 0.001). The length of hospital stay (10.9 ± 3.5 days versus 11.3 ± 4.0 days; P = 0.36) and anastomotic leakage (1.8% versus 0.5%; P = 0.20) were similar in both groups. No relevant differences between FEEA and ESA were observed for blood loss, retrieved lymph nodes, first flatus and postoperative complications.

Conclusion

An FEEA after right hemicolectomy for colon cancer is a safe and reliable anastomotic technique, resulting in a favorable outcome in selected patients with the right colon cancer.

Histopathologic advantages of compression ring anastomosis healing as compared with stapled anastomosis in a porcine model: a blinded comparative study

BACKGROUND

The performances of compression and stapled devices were compared previously in porcine colorectal anastomosis. The compression anastomosis was associated with elevated bursting strength and anastomotic patency in this model as compared with the stapled anastomosis.

OBJECTIVE

The purpose of this work was to compare the histopathologic features between compression and stapled methods in the healing of colorectal anastomoses using a porcine model.

DESIGN

This was a blinded comparison study.

SETTINGS

The study was conducted at a single university surgery department.

PATIENTS

Fifty crossbred pigs were used in this study.

MAIN OUTCOME MEASURES

Fifty crossbred pigs underwent rectal transection 20 cm from the anal verge and end-to-end compression or stapled anastomosis. The anastomotic tissues were harvested 3, 7, 30, and 90 days postoperatively (n = 5-6). Tissue repair parameters associated with the wound healing were analyzed using image analysis morphometry and histological architecture assessments.

RESULTS

A different microscopic pattern of the anastomotic area was shown between groups. Foreign body response was rated (p < 0.001) as minimal in the compression and moderate in the stapled group. The scarring area in the compression anastomosis group, on postoperative day 90 (4 ± 3 × 10(5) μm) was lower (p = 0.016) than in the stapled group (2 ± 1 × 10(6) μm). In addition, the anastomotic line was narrower (p = 0.003) 90 days after surgery in the compression samples (0.77 ± 0.20 mm) compared with that in the stapled group (1.86 ± 0.19 mm). Lastly, in terms of inflammatory cells, the compression biopsies showed lower (p < 0.001) numbers of mononuclear cells, polymorphonuclear cells, and lymphocytes in the anastomotic tissues 30 and 90 days from surgery.

LIMITATIONS

The long-term effect of the compression technique on the anastomotic patency in colorectal anastomoses should be further investigated in human studies.

CONCLUSIONS

Compression anastomotic healing was associated with less foreign body reactions, scarring, and inflammation as compared with stapled anastomoses in a large animal model.

"Tie over ring" sutureless compression based gastrointestinal anastomotic method: experimental rat model

INTRODUCTION

Giving the ever-rising trend of pediatric minimally invasive surgery besides early neonatal surgical interventions, intestinal anastomosis turns out to be a time consuming stage due to several anatomical as well as technical difficulties. A perfect bowel anastomosis method should be easy, rapid, safe and reliable in creation of bowel continuity with minimal tissue damage. In this light, sutureless anastomotic methods have been introduced, using compression based anastomosis with biofragmentable rings or powerful magnets. Accordingly, this experimental animal model study has evaluated the result of an easy, rapid intestinal sutureless anastomotic technique via simple tying over an intraluminal ring, in comparison with conventional handsewn bowel anastomosis.

METHODOLOGY

Thirty Wistar-Albino male rats were enrolled and small bowel was transected via a midline laparotomy. A grooved plastic ring was inserted into the ileal lumen and both intestinal cutting ends were fixed over the ring with a simple tie in the first group. On the other hand, enteroenterostomy was performed by the conventional method of handsewn anastomosis in the second group. After 14 days, rats were sacrificed to evaluate for intraperitoneal adhesion and abscess formation in addition to other evidences of anastomotic leakage. Furthermore, the anastomotic site integrity, tensile strength and healing stage were assessed microscopically.

RESULTS

The mean operative time and intraoperative bleeding in the tie over ring group were significantly less than those in the handsewn anastomosis group. Anastomotic stricture was more common in the conventional anastomosis group while the anastomotic tensile strength was significantly higher in the tie over ring group. Histopathological healing parameters and final healing score were almost similar in both groups but mean inflammatory cell infiltration in handsewn anastomosis was significantly higher.

CONCLUSION

"Tie over ring" is a simple method of anastomosis that is feasible, fast, safe and functionally effective for bowel reconstruction in animal models that could be reconsidered in human bowel anastomosis.

Anastomotic leakage after low anterior resection for rectal cancer: comparison of stapled versus compression anastomosis

PURPOSE

Surgical technique and perioperative management in rectal cancer surgery have been substantially improved and standardized during the last decades. However, anastomotic leakage following low anterior resection still is a significant problem. Based on animal experimental data of improved healing of compression anastomosis, we hypothesized that a compression anastomotic device might improve healing rates of the highest-risk anastomoses.

METHODS

All low anterior resections for rectal cancer performed or directly supervised by the senior author between January 2004 and June 2012 were analyzed. Only patients with a stapled or compression anastomosis located within 6 cm from the anal verge were included. Until December 2008, circular staplers were employed, while since January 2009, a novel compression anastomotic device was used for rectal reconstruction exclusively.

RESULTS

Out of 197 patients operated for rectal cancer, a total of 96 (34 females, 35.4 %) fulfilled inclusion criteria. Fifty-eight (60.4 %) were reconstructed with circular staplers and 38 (39.6 %) using a compression anastomotic device. Significantly, more laparoscopic procedures were recorded in the compression anastomosis group, but distribution of gender, age, body mass index, American Society of Anaesthesiologists score, rate of preoperative radiotherapy, tumor staging, or stoma diversion rate were similar. Anastomotic leakage was observed in seven cases (7/58, 12.1 %) in the stapled and twice (2/38, 5.3 %) in the compression anastomosis group (p = 0.26).

CONCLUSIONS

In this series, rectal reconstruction following low anterior resection using a novel compression anastomotic device was safe and (at least) equally effective compared to traditional circular staplers concerning leak rate.