Colon Stricture After Ischemia Following a Robot-Assisted Ultra-Low Anterior Resection With Coloanal Anastomosis

Prolonged ischemia of the ileum and colon after surgical mucosectomy explains contraction and failure of "mucus free" bladder augmentation

INTRODUCTION

Mucus production by the intestinal segment used in bladder augmentation results in long term concerns especially stones and UTI. Bladder augmentation with demucosalized intestinal flap is a potential promising approach for mucus-free bladder augmentation, however the contraction of the flap remains a major concern. Mucosectomy has been shown to result in abrupt and immediate cessation of microcirculation in the ileum. However, assessment of microcirculation shortly after mucosectomy may miss a gradual recovery of micro-circulation over a longer period of time. Previous studies have not assessed the colon response to mucosectomy.

OBJECTIVE

Our aim was to assess the effect of mucosectomy on the microcirculation of the colon and ileum beyond the known warm ischemia time.

STUDY DESIGN

Ileum and colon segments were detubularised and mucosectomy was performed in (n = 8) anesthetised minipigs. Group A: sero-musculo-submucosal flaps were created with removal of the mucosa and preserving the submucosal layer Group B: sero-muscular flaps were created with the removal of submucosal-mucosal layer. The Microvascular Flow Index (MFI), the velocity of the circulating red blood cells (RBCV) was measured using Intravital Dark Field (IDF) side stream videomicroscopy (Cytoscan Braedius, The Netherlands) after mucosectomy, for up to 180 min.

RESULTS

Both the MFI and RBCV showed an abrupt reduction of microcirculation, on both surfaces of the remaining intestinal flap, in the ileum as well as in the colon. Slightly better values were seen in Group A of the colon, but even these values remain far below the preoperative (control) results. Some, tendency of recovery of the microcirculation was noted after 60-90 min, but this remained significantly lower than the preoperative control values at 180 min.

CONCLUSION

Both the ileal and the colonic flap remains in severe ischemia after mucosectomy beyond the warm ischemia time.

DISCUSSION

This study shows that surgical mucosectomy compromises vascular integrity of the intestinal flaps used for bladder augmentation. Partial recovery which occurs within the warm ischemia time is not significant enough to avoid fibrosis therefore flap shrinkage may be inevitable with this technique.

LIMITATION

The gastrointestinal structure of the porcine model is not the same exactly as the human gastrointestinal system. However, although not an exact match it is the closest, readily available animal model to the human gastrointestinal system.

Robotic Intersphincteric Resection for Low Rectal Cancer: Technical Controversies and a Systematic Review on the Perioperative, Oncological, and Functional Outcomes

Intersphincteric resection (ISR) is the ultimate anus-sparing technique for low rectal cancer and is considered an oncologically safe alternative to abdominoperineal resection. The application of the robotic approach to ISR (RISR) has been described by few specialized surgical teams with several differences regarding approach and technique. This review aims to discuss the technical aspects of RISR by evaluating point by point each surgical controversy. Moreover, a systematic review was performed to report the perioperative, oncological, and functional outcomes of RISR. Postoperative morbidities after RISR are acceptable. RISR allows adequate surgical margins and adequate oncological outcomes. RISR may result in severe bowel and genitourinary dysfunction affecting the quality of life in a portion of patients.

Risk factors including the presence of inflammation at the resection margins for colorectal anastomotic stenosis following surgery for diverticular disease

AIM

The aim of this study was to investigate risk factors for anastomotic stenosis in patients operated on for diverticular disease. Histological inflammation and diverticula at the resection margins were also considered.

METHOD

Patients' characteristics, the surgical technique and postoperative complications were collected from the medical records. Anastomotic stenoses were evaluated prospectively by rigid sigmoidoscopy during follow-up examination. Histological specimens were examined by a single pathologist who investigated inflammation and diverticula at the resection margins. Twenty patients with anastomotic colorectal stenosis from a single tertiary centre were compared with 24 consecutive patients without stenosis. They were all operated on for diverticular disease over a specified time period.

RESULTS

Histological inflammation and diverticula were found in 25% and 30% of the resection margins respectively. Univariate analysis showed that age > 71 years (P = 0.0002), female gender (P = 0.0069) and anastomoses located below 12 cm from the anal verge (P = 0.020) were risk factors for stenosis. No correlation was found between anastomotic stenosis and the presence of histological inflammation or diverticula at the resection margins. By multivariate analysis, only age > 71 years was found to be a statistically significant risk factor for stenosis (P = 0.0003, OR = 60.8, 95% CI: 6.4-575.5).

CONCLUSION

Anastomotic stenosis is a frequent, long-term complication following surgery for diverticular disease. An analysis demonstrated that age is a risk factor for colorectal stenosis and that histological inflammation and the presence of diverticula near/at the resection margins have no effect on the incidence of stenosis.

Vascular anatomy of inferior mesenteric artery in laparoscopic radical resection with the preservation of left colic artery for rectal cancer

AIM

To investigate the vascular anatomy of inferior mesenteric artery (IMA) in laparoscopic radical resection with the preservation of left colic artery (LCA) for rectal cancer.

METHODS

A total of 110 patients with rectal cancer who underwent laparoscopic surgical resection with preservation of the LCA were retrospectively reviewed. A 3D vascular reconstruction was performed before each surgical procedure to assess the branches of the IMA. During surgery, the relationship among the IMA, LCA, sigmoid artery (SA) and superior rectal artery (SRA) was evaluated, and the length from the origin of the IMA to the point of branching into the LCA or common trunk of LCA and SA was measured. The relationship between inferior mesenteric vein (IMV) and LCA was also evaluated.

RESULTS

Three vascular types were identified in this study. In type A, LCA arose independently from IMA (46.4%, n = 51); in type B, LCA and SA branched from a common trunk of the IMA (23.6%, n = 26); and in type C, LCA, SA, and SRA branched at the same location (30.0%, n = 33). The difference in the length from the origin of IMA to LCA was not statistically significant among the three types. LCA was located under the IMV in 61 cases and above the IMV in 49 cases.

CONCLUSION

The vascular anatomy of the IMA and IMV is essential for laparoscopic radical resection with preservation of the LCA for rectal cancer. To recognize different branches of the IMA is necessary for the resection of lymph nodes and dissection of vessels.

Surgical specimen extraction via a prophylactic ileostomy procedure: A minimally invasive technique for laparoscopic rectal cancer surgery

AIM

To retrospectively evaluate the safety and feasibility of surgical specimen extraction via a prophylactic ileostomy procedure in patient with rectal cancer.

METHODS

We systematically reviewed 331 consecutive patients who underwent laparoscopic anterior resection for rectal cancer and prophylactic ileostomy in our institution from June 2010 to October 2016, including 155 patients who underwent specimen extraction via a prophylactic ileostomy procedure (experimental group), and 176 patients who underwent specimen extraction via a small lower abdominal incision (control group). Clinical data were collected from both groups and statistically analyzed.

RESULTS

The two groups were matched in clinical characteristics and pathological outcomes. However, mean operative time was significantly shorter in the experimental group compared to the control group (161.3 ± 21.5 min vs 168.8 ± 20.5 min; P = 0.001). Mean estimated blood loss was significantly less in the experimental group (77.4 ± 30.7 mL vs 85.9 ± 35.5 mL; P = 0.020). The pain reported by patients during the first two days after surgery was significantly less in the experimental group than in the control group. No wound infections occurred in the experimental group, but 4.0% of the controls developed wound infections (P = 0.016). The estimated 5-year disease-free survival and overall survival rate were similar between the two groups.

CONCLUSION

Surgical specimen extraction via a prophylactic ileostomy procedure represents a secure and feasible approach to laparoscopic rectal cancer surgery, and embodies the principle of minimally invasive surgery.