Intraoperative Monitoring of Bladder and Internal Anal Sphincter Innervation: A Predictor of Erectile Function following Low Anterior Rectal Resection for Rectal Cancer? Results of a Prospective Clinical Study

Background: Even in the case of minimally invasive pelvic surgery, sparing of the autonomic nerve supply is a prerequisite for maintaining anal sphincter function. Internal anal sphincter (IAS) innervation could be electrophysiologically identified based on processed electromyographic (EMG) recordings with conventional bipolar needle electrodes (NE). This experimental study aimed for the development of a minimally invasive approach via intra-anal surface EMG for recordings of evoked IAS activity. Methods: Six male pigs underwent nerve-sparing low anterior rectal resection. Electric autonomic nerve stimulations were performed under online-processed EMG of the IAS. EMG recordings were simultaneously carried out with conventional bipolar NE as the reference method and newly developed intra-anal surface electrodes (SE) in different designs. Results: In all experiments, the IAS activity could be continuously visualized via EMG recordings based on NE and SE. The median number of bipolar electric stimulations per animal was 27 (range 5-52). The neurostimulations resulted in significant EMG amplitude increases for both recording types [NE: median 3.0 µV (interquartile range, IQR 2.8-3.5) before stimulation vs. 7.1 µV (IQR 3.9-13.8) during stimulation, p < 0.001; SE: median 3.6 µV (IQR 3.1-4.3) before stimulation vs. 6.8 µV (IQR 4.8-10.3) during stimulation, p < 0.001]. Conclusions: Intra-anal SE enabled reliable EMG of electrophysiologically evoked IAS activity similar to the conventional recording via NE. The transfer of the method to access platforms for transanal total mesorectal excision or robotics may offer a practical more minimally invasive approach for monitoring extrinsic innervation.

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Prediction of anastomotic leakage after anterior rectal resection

Pakistan Journal of Medical Sciences ◽

10.12669/pjms.35.3.252 ◽

2019 ◽

Vol 35 (3) ◽

Cited By ~ 2

Author(s):

Shubang Cheng ◽

Bolin He ◽

Xueyi Zeng

Keyword(s):

Rectal Cancer ◽

Prediction Model ◽

Anastomotic Leakage ◽

Roc Curve ◽

Rectal Resection ◽

Preoperative Chemoradiotherapy ◽

Tumor Differentiation ◽

Intraoperative Bleeding ◽

Anterior Rectal Resection ◽

Validation Set

Objective: Anastomotic Leakage (AL) is one of the most common complications after resection of rectal cancer. Recognition of the incidence and risk factors related to AL is important. This study aimed develops a model that can predict anastomotic leakage after anterior rectal resection. Methods: Data from 188 patients undergoing anterior resection of rectal cancer were collected for retrospective analysis. Patients were randomly divided in the development set and validation set at a 1:1 ratio. We first included age, sex, preoperative chemoradiotherapy, tumor size, degree of tumor differentiation, stage, TNM stage, lymph vascular invasion, distance, anastomotic method, diabetes, intraoperative time, intraoperative bleeding and smoking as candidates for variable selection with a LASSO method. A ROC curve was constructed with the validation set to assess the accuracy of the prediction model. Results: AL occurred in 20 of 188 patients (10.6%). Preoperative chemoradiotherapy (p=0.04), medium degree of tumor differentiation (p=0.04), anastomotic method (p<0.01), intraoperative bleeding≥400ml (p<0.01), smoking (p<0.01), diabetes (p<0.01) were significantly related to AL. The area under the ROC curve of the prediction model is 0.952. Conclusions: This study developed a model that can predict anastomotic leakage after anterior rectal resection, which may aid the selection of preventive ileostomy and postoperative management. doi: https://doi.org/10.12669/pjms.35.3.252 How to cite this:Cheng S, He B, Zeng X. Prediction of anastomotic leakage after anterior rectal resection. Pak J Med Sci. 2019;35(3):830-835. doi: https://doi.org/10.12669/pjms.35.3.252 This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

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