Intestinal Anastomotic Healing: What do We Know About Processes Behind Anastomotic Complications

Plastic Wound Protector vs Surgical Gauze for Surgical Site Infection Reduction in Open GI Surgery: A Randomized Clinical Trial

Importance

Surgical site infections (SSIs) are prevalent hospital-acquired infections with significant patient impacts and global health care burdens. The World Health Organization recommends using wound protector devices in abdominal surgery as a preventive measure to lower the risk of SSIs despite limited evidence.

Objective

To examine the efficacy of a dual-ring, plastic wound protector in lowering the SSI rate in open gastrointestinal (GI) surgery irrespective of intra-abdominal contamination levels.

Design, Setting, and Participants

This multicenter, patient-blinded, parallel-arm randomized clinical trial was conducted from August 2017 to October 2022 at 13 hospitals in an academic setting. Patients undergoing open abdominal bowel surgery (eg, for bowel perforation) were eligible for inclusion.

Intervention

Patients were randomized 1:1 to a dual-ring, plastic wound protector to protect the incision site of the abdominal wall (experimental group) or a conventional surgical gauze (control group).

Main Outcomes and Measures

The primary end point was the rate of SSI within 30 days of open GI surgery.

Results

A total of 458 patients were randomized; after 1 was excluded from the control group, 457 were included in the intention-to-treat analysis (mean [SD] age, 58.4 [12.1] years; 256 [56.0%] male; 341 [74.6%] with a clean-contaminated wound): 229 in the wound protector group and 228 in the surgical gauze group. The overall SSI rate in the intention-to-treat analysis was 15.7% (72 of 458 patients). The SSI rate for the wound protector was 10.9% (25 of 229 patients) compared with 20.5% (47 of 229 patients) with surgical gauze. The wound protector significantly reduced the risk of SSI, with a relative risk reduction (RRR) of 46.81% (95% CI, 16.64%-66.06%). The wound protector significantly decreased the SSI rate for clean-contaminated wounds (RRR, 43.75%; 95% CI, 3.75%-67.13%), particularly for superficial SSIs (RRR, 42.50%; 95% CI, 7.16%-64.39%). Length of hospital stay was similar in both groups (mean [SD], 15.2 [10.5] vs 15.3 [10.2] days), as were the overall postoperative complication rates (20.1% vs 18.8%).

Conclusions and Relevance

This randomized clinical trial found a significant reduction in SSI rates when a plastic wound protector was used during open GI surgery compared with surgical gaze, supporting the World Health Organization recommendation for use of wound protector devices in abdominal surgery.

Trial Registration

ClinicalTrials.gov Identifier: NCT03170843.

Does Tri-Staple™ technology reduce the risk of anastomotic leakage in colorectal surgery? A propensity score matching analysis

BACKGROUND AND OBJECTIVES

This study evaluates the Tri-Staple™ technology in colorectal anastomosis.

METHODS

Patients who underwent rectosigmoidectomy between 2016 and 2022 were retrospectively evaluated and divided into two groups: EEA™ (EEA) or Tri-Staple™ (Tri-EEA). The groups were matched for age, sex, American Society of Anesthesiologists (ASA), and neoadjuvant radiotherapy using propensity score matching (PSM).

RESULT

Three hundred and thirty-six patients were included (228 EEA; 108 Tri-EEA). The groups were similar in sex, age, and neoadjuvant therapy. The Tri-EEA group had fewer patients with ASA III/IV scores (7% vs. 33%; p < 0.001). The Tri-EEA group had a lower incidence of leakage (4% vs. 11%; p = 0.023), reoperations (4% vs. 12%; p = 0.016), and severe complications (6% vs. 14%; p = 0.026). There was no difference in complications, mortality, readmission, and length of stay. After PSM, 108 patients in the EEA group were compared with 108 in the Tri-EEA group. The covariates sex, age, neoadjuvant radiotherapy, and ASA were balanced, and the risk of leakage (4% vs. 12%; p = 0.04), reoperation (4% vs. 14%; p = 0.014), and severe complications (6% vs. 15%; p = 0.041) remained lower in the Tri-EEA group.

CONCLUSION

Tri-Staple™ reduces the risk of leakage in colorectal anastomosis. However, this study provides only insights, and further research is warranted to confirm these findings.

A novel discrete linkage-type electrode for radiofrequency-induced intestinal anastomosis

INTRODUCTION

For decades, radiofrequency (RF)-induced tissue fusion has garnered great attention due to its potential to replace sutures and staples for anastomosis of tissue reconstruction. However, the complexities of achieving high bonding strength and reducing excessive thermal damage present substantial limitations of existing fusion devices.

MATERIALS AND METHODS

This study proposed a discrete linkage-type electrode to carry out ex vivo RF-induced intestinal anastomosis experiments. The anastomotic strength was examined by burst pressure and shear strength test. The degree of thermal damage was monitored through an infrared thermal imager. And the anastomotic stoma fused by the electrode was further investigated through histopathological and ultrastructural observation.

RESULTS

The burst pressure and shear strength of anastomotic tissue can reach 62.2 ± 3.08 mmHg and 8.73 ± 1.11N, respectively, when the pressure, power and duration are 995 kPa, 160 W and 13 s, and the thermal damage can be controlled within limits. Histopathological and ultrastructural observation indicate that an intact and fully fused stomas with collagenic crosslink can be formed.

CONCLUSION

The discrete linkage-type electrode presents favorable efficiency and security in RF-induced tissue fusion, and these results are informative to the design of electrosurgical medical devices with controllable pressure and energy delivery.

Collagen patch cover facilitates recovery of bowel function after laparoscopic colectomy

BACKGROUND

Numerous factors can influence bowel movement recovery and anastomotic healing in colorectal surgery, and poor healing can lead to severe complications and increased medical expenses. Collagen patch cover (CPC) is a promising biomaterial that has been demonstrated to be safe in animal models and has been successfully applied in various surgical procedures in humans. This study.

METHODS

A retrospective review of medical records from July 2020 to June 2022 was conducted to identify consecutive patients who underwent laparoscopic colectomy. Patients who received CPC at the anastomotic site were assigned to the collagen group, whereas those who did not receive CPC were assigned to the control group.

RESULTS

Data from 241 patients (collagen group, 109; control group, 132) were analyzed. Relative to the control group, the collagen group exhibited a faster recovery of bowel function, including an earlier onset of first flatus (2.93 days vs. 3.43 days, p < 0.01), first defecation (3.73 days vs. 4.18 days, p = 0.01), and oral intake (4.30 days vs. 4.68 days, p = 0.04). CPC use was also associated with lower use of postoperative intravenous analgesics. The complication rates in the two groups did not differ significantly.

CONCLUSIONS

CPCs can be safely and easily applied to the anastomotic site during laparoscopic colectomy, and can accelerate bowel movement recovery. Further studies on the effectiveness of CPCs in colorectal surgery involving larger sample sizes are required.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov registration number: NCT05831956 (26/04/2023).

Promoting wound recovery through stable intestinal flora: Reducing post-operative complications in colorectal cancer surgery patients

In recent years, the relationship between intestinal flora and post-operative recovery, particularly in colorectal cancer (CRC) surgery patients, it has been hypothesized that intestinal flora stability influences wound healing, reduces complications and improves overall recovery outcomes after surgical interventions. This study examined the relationship between intestinal flora stability and post-operative recovery in patients undergoing CRC surgery. Between May 2020 and 2023, 80 CRC patients from our hospital's Colorectal Surgery Department were enrolled. A random number table was used to divide them into two categories. Both groups were subjected to distinct gastrointestinal preparation protocols. Indicators of clinical therapeutic effect, intestinal flora balance following surgery, post-operative complications and quality of life were evaluated. The observation group, which adhered to a distinct gastrointestinal regimen, demonstrated a statistically significant improvement in post-operative outcomes, with a clinical effectiveness rate of 97.5% compared to the control group's 75%. In addition, the observation group had a lower incidence of intestinal flora imbalance following surgery than the control group. The observation group had lower incidences of intestinal obstruction, infection, anastomotic leakage, incisional tumour implantation and delayed diarrhoea. Using the KPS score and the BMI, post-treatment assessments of the observation group's quality of life revealed significant enhancements in comparison to the control group. Additionally, wound healing rates were superior in the observation group, with a correlation between stable intestinal flora and decreased wound infection rates. The type of post-operative diet influenced the stabilization of the gut flora, with a high-fibre diet producing superior results in both groups. The stability of intestinal flora influences the post-operative rehabilitation of patients undergoing CRC surgery favourably. Appropriate bowel preparation and dietary considerations can reduce post-operative complications, improve wound healing rates and enhance overall quality of life.

Biologically inspired gastrointestinal stapler design: "Getting to Zero" complications

As next generation stapling devices enter the marketplace with robotic adaptations, tri-staple technology, preloaded reinforcement materials, etc., in this perspective piece we assert that a "refresh" in our understanding of the mechanisms of action of these devices is needed. While much attention has been paid to explain the mechanical features of one device versus another, it seems that little to no attention is being paid to understand how an intestinal anastomosis responds biologically to the variations in their use and design. Here we will review various aspects of gastrointestinal stapling in the context of emerging technology in the field and expose the gaps in knowledge that exist regarding the effect of gastrointestinal stapling on the biology of healing.

Intraperitoneal BromAc® Does Not Interfere with the Healing of Colon Anastomosis

A combination of bromelain and acetylcysteine, BromAc^®, is an efficient intraperitoneal mucolytic for thick mucus secreted in pseudomyxoma peritonei (PMP). Patients with PMP quite often undergo colon anastomosis. Hence, we investigated the effect of the intraperitoneal delivery of BromAc^® on colon-anastomosis healing in a rat model. Sixteen Wistar rats were divided into two groups (N = 8). The controls received intraperitoneal saline after anastomosis, whilst the other group received BromAc^®. They were monitored for body-weight and general health parameters. Half the rats in each group (N = 4) were culled at 4 or 13 days post-surgery for assessment. The healing process of the tissues was assessed by burst pressure and collagen density with histology to assess the integrity of the internal organs. The results indicated that there was a similar pattern of weight fluctuation during the experiment, although the rats treated with the BromAc^® showed slightly greater weight loss during the first 4 days. Although the burst pressure was similar in both groups, the BromAc^® group at day 13 showed a slightly higher burst pressure, which was complemented by a higher collagen density (albeit not statistically significant). The histology of the internal organs was comparable to those of the controls. This study indicates that the intraperitoneal delivery of BromAc^® in a rat model does not interfere with the healing process of colonic anastomosis.

Histological mapping of healing of the small and large intestine – a quantitative study in a porcine model

BACKGROUND

Gastrointestinal anastomoses are performed in many patients every year. The pathogenesis of aberrant anastomotic healing and the causes of intestinal leakage are not fully understood. The present study gathered and critically evaluated histological quantitative data to deepen current knowledge of anastomotic healing in the small and large intestine and its complications and outline the options for further experimental in vivo research in large porcine animal models.

METHODS

Three groups of porcine intestinal anastomoses were compared: small intestine without defect (SI; n=7), small intestine with an additional defect (SID; n=8), and large intestine (LI; n=7). Multilevel sampling (2,112 micrographs) and stereological methods were used for histological quantification of proliferation (Ki-67 immunohistochemistry), neutrophil infiltration (myeloperoxidase staining), vascularity (von Willebrand factor) and type I and type III collagen formation (picrosirius red in polarized light) within the region of anastomosis compared to the region outside of anastomosis.

RESULTS

Quantitative histological evaluation revealed the following results. i) Proliferation, vascularity, and collagen, but not neutrophils, were more highly expressed within the anastomosis than outside of the anastomosis region. ii) Porcine large and small intestine were not interchangeable based on histological evaluation of surgical experiments. The presence or absence of an additional experimental defect strongly affected healing, but the healing seemed complete after 21 days. iii) The microscopic structure of small intestine segments was more affected by their proximity to the anastomosis than the structure of large intestine segments.

CONCLUSIONS

Histological quantification was more laborious than the previously used semiquantitative scoring system evaluating the healing rate of intestinal anastomoses, but it provided detailed maps of biological processes within individual intestine layers. The primary data collected in the study are open and available for power sample analyses to calculate the minimum numbers of samples justified in future experiments on porcine intestines. The porcine intestine is a promising animal model with translational potential for human surgery.

Gaining Mesenteric Length following Colorectal Resection: Essential Maneuvers to Avoid Anastomotic Tension

A surgeon must possess the knowledge and technical skill to obtain length following a left-sided colorectal resection to perform a tension free anastomosis. The distal target organ - either rectum or anus - is fixed in location, and therefore requires surgeons to acquire mastery of proximal mobilization of the colonic conduit. Generally, splenic flexure mobilization (SFM) provides adequate length. Surgeons benefit from clearer understanding of the multiple steps involved in SFM as a result of improved visualization and demonstration of the relevant anatomy - adjacent organs and the attachments, embryologic planes, and mesenteric structures. Much may be attributed to laparoscopic and robotic platforms which provided improved exposure and as a result, development or refinement of novel approaches for SFM with potential advantages. Complete mobilization draws upon the sum or combination of the varied approaches to accomplish the goal. However, in the situation where extended resection is necessary or in the case of re-operative surgery sacrificing either more proximal or distal large intestine often occurs, the transverse colon or even the ascending colon represents the proximal conduit for anastomosis. This challenging situation requires familiarity with special maneuvers to achieve colorectal or coloanal anastomosis using these more proximal conduits. In such instances, operative techniques such as either ileal mesenteric window with retroileal anastomosis or de-rotation of the right colon (Deloyer's procedure) enable the intestinal surgeon to construct such anastomoses and thereby avoid stoma creation or loss of additional large intestine.