[Predictive models and prophylactic strategies for anastomotic leakage in colorectal surgery].

Anastomotic leakage (AL) has always been a persistent issue for colorectal surgeons. It is still difficult to reduce the incidence of AL despite the advances in technology and equipment. With the development of evidence-based medicine, increasing high-risk factors for AL have been identified. How to efficiently and systematically combine and quantify these isolated risk factors to provide a scientific early warning of AL in clinical practices and help surgeons in choosing the optimal prophylactic strategies, is of great significance for reducing the incidence of AL. There are generally two types of AL prediction models in colorectal surgery, including prognostic models (for preoperative and intraoperative AL prediction) and diagnostic models (for early warning and improving the early diagnosis rate of AL). Prophylactic strategies for AL include stabilizing the underlying diseases, improving anemia and hypoalbuminemia, choosing an appropriate operative time window, and emphasizing and improving anastomotic techniques (including choosing an appropriate size of stapler). However, a prophylactic ostomy is still the most common method for surgeons. However, how to reduce the morbidity of complications following prophylactic ostomy and how to avoid the conversion of the prophylactic stoma to permanent stoma need further study.

[Preliminary application and efficacy analysis of transumbilical single-incision plus one port robotic total mesorectal excision].

Objective: To investigate the feasibility of transumbilical single-incision plus one port (SIPOP) robotic total mesorectal excision. Methods: Clinical data of a 70-year-old male patient with BMI 22.1 kg/m(2) who successfully underwent transumbilical single-incision plus 1 port robotic total mesorectal resection of upper rectal cancer at the General Surgery Department of Daping Hospital of Army Military Medical University on September 18, 2019 were retrospectively analyzed. Preoperative colonoscopy revealed that the distance of upper rectal cancer to anal edge was 14 cm, and the tumor size was 2.5 cm×1.5 cm×1 cm. Pathological result confirmed rectal moderately differentiated adenocarcinoma. The preoperative abdominal CT showed thickened bowel-wall of upper rectum and the blurred perirectal fat, suggesting tumor infiltration. Results: The operation was successful. There were no conversion to laparotomy or abdominal auxiliary incision, and the mesorectum of the specimen was intact. The operation time was 165 minutes, the blood loss was about 20 ml, and there were no complications such as injury to peripheral organs. Postoperative pathology showed ulcerative moderately differentiated adenocarcinoma of the upper rectum with TNM stage IVA (T4N2b). The postoperative recovery was smooth. Patient ambulated on the 1st day, the catheter was removed on the 7th day, and discharged from the hospital on the 8th day. Conclusion: The transumbilical SIPOP robotic total mesorectal excision is safe, effective and feasible.

[Incidence and risk factors of anastomotic leak after transanal total mesorectal excision in China: a retrospective analysis based on national database].

Objective: Transanal total mesorectal excision (taTME) was a very hot topic in the first few years since its appearance, but now more introspections and controversies on this procedure have emerged. One of the reasons why the Norwegian Ministry of Health stopped taTME was the high incidence of postoperative anastomotic leak. In current study, the incidence and risk factors of anastomotic leak after taTME were analyzed based on the data registered in the Chinese taTME Registry Collaborative (CTRC). Methods: A case-control study was carried out. Between November 15, 2017 and December 31, 2020, clinical data of 1668 patients undergoing taTME procedure registered in the CTRC database from 43 domestic centers were collected retrospectively. After excluding 98 cases without anastomosis and 109 cases without complete postoperative complication data, 1461 patients were finally enrolled for analysis. There were 1036 males (70.9%) and 425 females (29.1%) with mean age of (58.2±15.6) years and mean body mass index of (23.6±3.8) kg/m(2). Anastomotic leak was diagnosed and classified according to the International Study Group of Rectal Cancer (ISREC) criteria. The risk factors associated with postoperative anastomotic leak cases were analyzed. The impact of the cumulative number of taTME surgeries in a single center on the incidence of anastomotic leak was evaluated. As for those centers with the number of taTME surgery ≥ 40 cases, incidence of anastomic leak between 20 cases of taTME surgery in the early and later phases was compared. Results: Of 1461 patients undergoing taTME, 103(7.0%) developed anastomotic leak, including 71 (68.9%) males and 32 (31.1%) females with mean age of (59.0±13.9) years and mean body mass index of (24.5±5.7) kg/m(2). The mean distance between anastomosis site and anal verge was (2.6±1.4) cm. Thirty-nine cases (37.9%) were classified as ISREC grade A, 30 cases (29.1%) as grade B and 34 cases (33.0%) as grade C. Anastomotic leak occurred in 89 cases (7.0%,89/1263) in the laparoscopic taTME group and 14 cases (7.1%, 14/198) in the pure taTME group. Multivariate analysis showed that hand-sewn anastomosis (P=0.004) and the absence of defunctioning stoma (P=0.013) were independently associated with anastomotic leak after taTME. In the 16 centers (37.2%) which performed ≥ 30 taTME surgeries with cumulative number of 1317 taTME surgeries, 86 cases developed anastomotic leak (6.5%, 86/1317). And in the 27 centers which performed less than 30 taTME surgeries with cumulative number of 144 taTME surgeries, 17 cases developed anastomotic leak (11.8%, 17/144). There was significant difference between two kinds of center (χ(2)=5.513, P=0.019). Thirteen centers performed ≥ 40 taTME surgeries. In the early phase (the first 20 cases in each center), 29 cases (11.2%, 29/260) developed anastomotic leak, and in the later phase, 12 cases (4.6%, 12/260) developed anastomotic leak. The difference between the early phase and the later phase was statistically significant (χ(2)=7.652, P=0.006). Conclusion: The incidence of anastomotic leak after taTME may be reduced by using stapler and defunctioning stoma, or by accumulating experience.

[Initial report of laparoscopic single incision plus one port with simultaneous robotic-assisted transanal total mesorectal excision for low rectal cancer surgery].

Robotic-assisted transanal total mesorectal excision (R-TaTME) has unique advantage in low rectal cancer. Single incision plus oneport (SIPOP) laparoscopic operation can synchronously cooperate with robotic-assisted transanal operation, in order to the difficulty of operation, improve the quality of operation and shorten the time of operation. A retrospective analysis was conducted on the clinical and pathological data of one patient who underwent SIPOP synchronously combined with R-TaTME + sigmoid-anal anastomosis + ileostomy at the Department of General Surgery, Army Characteristic Medical Center on September 11, 2019. This 71-year-old patient was male with body mass index of 24.08 kg/m(2) and received preoperative chemotherapy. Rectal adenocarcinoma was confirmed by colonoscopy biopsy, and distance from tumor lower edge to anal verge was 3 cm. MRI indicated T2N1 stage. The operation was completed successfully, and the transabdominal and robotic transanal surgery totaled 117 minutes, with 15 minutes for the robotic transanal preparation step. There was about 20 ml of intraoperative blood loss and no blood transfusion was performed. The patient was discharged 6 days after operation. No intraoperative or postoperative complications occurred. The postoperative TNM staging was stage I (pyT2N0cM0). No recurrence or metastasis was found at postoperative 7 month. It is a safe, effective and feasible technique for patients with low rectal cancer.

[Application value of sedation in colonoscopy].

Objective: To investigate the value of sedation in colonoscopy. Methods: A retrospective cohort study of colonoscopy procedures was performed in our institution. Inclusion criteria: (1) colonoscopy procedures were performed by well-trained gastrointestinal surgeons our institution; (2) medical records were complete and colonoscopy was documented properly by notes, videos, photographs, and traceable pathological reports. Those with incomplete records or performed in other institution were excluded. According to above criteria, clinical data of 49 057 cases of clinic and hospitalization receiving diagnostic or therapeutic colonoscopyat Department of Gastric and Colorectal Surgery, Daping Hospital from July 2007 to February 2017 were collected. Among them, there were 24 638 (50.2%) males and 24 419 females, with mean age of (50.6±14.1) (4 to 98) years. Based on the application of sedation during colonoscopy, patients were divided into the sedation group (39 412 cases, 80.3%) and the non-sedation group (9 645 cases, 19.7%). Clinical characteristics of two groups were compared. Results: The sedation rate increased from 45.6% (369/810) to 94.8% (917/967) from 2007 to 2017. As compared to non-sedation group, a higher proportion of females [51.0% (20 095/39 412) vs. 44.8% (4 324/9 645), χ(2)=117.422, P<0.001] and younger median age (50.0 years vs. 51.0 years, Z=-4.774, P<0.001) were found in the sedation group, whose differences were statistically significant. In all the 9645 cases in the non-sedation group, about 5.5% (534) of them terminated the examination because of unbearable discomfort, including 244 (4.6%) males and 290 (6.7%) females (χ(2)=20.522, P<0.001). Among all the screening population who were ≥50 years old, there was no significant difference in the polyp detection rate (PDR) between the sedation group and the non-sedation group [26.7% (4 737/17 753) vs. 27.4% (1 093/3 984), χ(2)=0.937, P=0.330]. The cecal intubation rate (CIR) in the sedation group was significantly higher than that in the non-sedation group [(85.2% (14 422/16 933) vs. 76.1% (2 803/3 682), χ(2)=180.032, P<0.001]. Five cases in the sedation group developed iatrogenic colonic perforation (ICP), with none in the non-sedation group. Conclusions: The application of sedation in colonoscopy is increasingly popular. Sedation can significantly improve CIR in colonoscopy, while it has no positive influence on PDR. Meanwhile, sedation increases the medical expense and may result in higher ICP rate.

[The status analysis of diagnosis and treatment of synchronous peritoneal carcinomatosis from colorectal cancer in China: a report of 1 003 cases in 16 domestic medical centers].

Objective: To analyze the status of domestic surgical treatment of synchronous peritoneal carcinomatosis from colorectal cancer in China. Methods: Clinicopathological data of patients who underwent surgery from October 2003 to October 2018 in 16 domestic medical centers was retrospectively analyzed. Excel database was created which covered 77 fields of 7 parts: baseline information of patients, laboratory tests, imaging tests, chemoradiotherapy information, intra-operative findings, postoperative pathology and follow-up data. The Wilcoxon rank-sum test was used for comparison of the measurement data between groups. The χ(2) test was used for comparison of the categorical data between groups. The survival curve was calculated by the Kaplan-Meier method. Results: Of the 1 003 patients, there were 575 male and 428 female patients with the age of (58.5±14.1) years (range: 18 to 92 years). In a total of 920 patients, the carcinoma of sigmoid colon was performed in 292 cases (31.8%) with the highest ratio. The proportion of patients with liver metastasis and lung metastasis were 27.9% (219/784) and 8.3% (64/769). Preoperative detection of carcino-embryonic antigen level was the most common method in China (87.74%, 880/1 003), and the positive rate was 64.5% (568/880). The correct rate of preoperative imaging tests was 40.7% (280/688). The ratio of peritoneal carcinomatosis index (PCI) scores between 0 and 10 was the highest (59.6%, 170/285). Two hundred and sixty-two (27.0%) patients were performed by totally laparoscopic operation in 971 patients. The resection of primary tumor was performed in 588 of the 817 patients (72.0%). In a total of 457 cases, 253 (55.4%) patients were performed cytoreduction which group scored completeness of cytoreduction (CCR) 0. The postoperative hyperthermic intraperitoneal chemotherapy was implemented in 70 of the 334 cases (21.0%). Among 1 003 cases, 562 cases (56.03%) had complete follow-up data and the median overall survival was 15 months. The primary tumor resection and the CCR scores were affected by the PCI scores. The patients underwent primary tumor resection (187/205 vs. 26/80, χ(2)=105.085, P=0.000) and the patients were performed cytoreduction which scored CCR 0 or CCR 1 (162/204 vs. 8/78, Z=-10.465, P=0.000) had significant difference between the groups of PCI<20 and ≥20. There was a close correlation between the surgical method and the CCR scores (Z=-3.246,P=0.001).When the maximum degree of tumor reduction was planned, most surgeons would choose laparotomy. The overall survival time was longer in patients with primary tumor resection (P=0.000). The median survival time was 18.6 months in the group of primary tumor resection. Conclusions: It is difficult to diagnose the synchronous peritoneal carcinomatosis from colorectal cancer before the operation. Primary tumor resection has an obvious effect to prolong the survival time. It is necessary to standardize the treatment of peritoneal metastasis.

Effects of autonomic nerve stimulation on colorectal motility in rats.

BACKGROUND: Several disease processes of the colon and rectum, including constipation and incontinence, have been associated with abnormalities of the autonomic nervous system. However, the autonomic innervation to the colon and rectum are not fully understood. The aims of this study were to investigate the effect of stimulation of vagus nerves, pelvic nerves (PN) and hypogastric nerves (HGN) on colorectal motility in rats. METHODS: Four strain gauge transducers were implanted on the proximal colon, mid colon, distal colon and rectum to record circular muscle contractions in rats. Electrical stimulation was administered to the efferent distal ends of the cervical vagus nerve, PN and HGN. Motility index (MI) was evaluated before and during stimulation. KEY RESULTS: Electrical stimulation (5-20 Hz) of the cervical vagus elicited significant contractions in the mid colon and distal colon, whereas less pronounced contractions were observed in the proximal colon. Pelvic nerves stimulation elicited significant contractions in the rectum as well as the mid colon and distal colon. Atropine treatment almost completely abolished the contractions induced by vagus nerve and PN stimulation. Hypogastric nerves stimulation caused relaxations in the rectum, mid colon and distal colon. The relaxations in response to HGN stimulation were abolished by propranolol. CONCLUSIONS & INFERENCES: Vagal innervation extends to the distal colon, while the PN has projections in the distribution of the rectum through the mid colon. This suggests a pattern of dual parasympathetic innervation in the left colon. Parasympathetic fibers regulate colorectal contractions via muscarinic receptors. The HGN mainly regulates colorectal relaxations via beta-adrenoceptors.