| Objective:To establish a model for the conversion of laparoscopic rectal resection to open surgery and to predict possible conversion before surgery.Methods:A total of 6248 cases of laparoscopic rectectomy were comprehensively reviewed.Of these,551 required conversion (total conversion rate=8.82%), which included 100 cases due to technical reasons,411 cases due to non-technical reasons, and 40 cases due to accidental conversion. A review of the relevant literature indicated that possible risk factors for conversion from laparoscopic rectectomy included gender, age, obesity, history of abdominal surgery, tumor diameter of≥6 cm, tumor invasion or metastasis, surgical experience, hypertension, coronary heart disease, diabetes (with/without), anesthesia (American Society of Anesthesiologists (ASA) Physical Status classification score≥Ⅲ), etc. Possible risk factors for conversion were defined as follows:age≥65 years, obesity,body mass index (BMI)≥28, history of conventional lower abdominal surgery (open surgery); hypertension, coronary heart disease and diabetes of international standards, invasion or metastasis(tumor infiltration to surrounding tissues such as the uterus, prostate, and bladder or metastasis to the liver and lungs), surgical experience(< 25 cases of laparoscopic rectectomy) and preoperative tumor size≥6 cm, as determined by gastrointestinal endoscopy.A total of 602 cases of laparoscopic rectectomyperformed in our hospital from January 2001 to December 2013 were included for analysis. Conversion to open rectal surgery was required in 84 cases (total conversion rate=13.95%).All statistical analyses were performed usingSPSS v19.0 software (SPSS, Inc., Chicago, IL, USA). Multivariate logistic analysis was also performed because conversion was generally caused by multiple factors. The following risk factors were found to be associated with conversion:surgical experience, history of abdominal surgery, male, obesity, tumor diameter≥6 cm, and tumor invasion or metastasis. Theseresults wereconsistent with those in the literature. A formula to predict the probability of conversion was created by logistic analysis on these clinical data. We established a scoring system to predict possible conversion of laparoscopic rectectomy.Results:A total of 6248 cases of laparoscopic rectectomy were comprehensively reviewed. Of these,551 required conversion (total conversion rate=8.82%), whichincluded 100 cases due to technical reasons,411 due to non-technical reasons, and 40 due to accidental conversion.Adhesion (18.15%), Tumor invasion (16.70%), Tumor bulk (16.33%), Bleeding (9.26%). Exposure (7.80%), Tumor metastasis (5.44%), Obesity (4.36%), Instrument failure (3.99%), Bowel injury (2.54%), Narrow pelvis (2.36%), Bladder ureter injury (2.18%), Surgeon inexperience (1.81%), Infection (1.63%), Unexpected cancer(1.45%), Intestinal obstruction(1.09%), Anesthesia intolerance(0.91%), Bowel injury(O.73%), Expansion of the colon(0.45%).A review of the relevant literature indicated that possible risk factors for conversion fromlaparoscopic rectectomy included gender, age, obesity, history of abdominal surgery, tumor diameter of> 6 cm, tumor invasion or metastasis, surgical experience, hypertension, coronary heart disease, diabetes (with/without), anesthesia (American Society of Anesthesiologists (ASA) Physical Status classification score> Ⅲ), etc. Possible risk factors for conversion were defined as follows:age> 65 years, obesity,body mass index (BMI)≥ 28, history of conventional lower abdominal surgery (open surgery); hypertension, coronary heart disease and diabetes of international standards, invasion or metastasis(tumor infiltration to surrounding tissues such as the uterus, prostate, and bladder or metastasis to the liver and lungs), surgical experience(< 25 cases of laparoscopic rectectomy) and preoperative tumor size> 6 cm, as determined by gastrointestinal endoscopy.A total of 602 cases of laparoscopic rectectomyperformed in our hospital from January 2001 to December 2012 were included for analysis. Conversion to open rectal surgery was required in 84 cases (total conversion rate=14.95%).All statistical analyses were performed usingSPSS v19.0 software (SPSS, Inc., Chicago, IL, USA). Data were compared by univariate analysis. Multivariate logistic analysis was also performed because conversion was generally caused by multiple factors. The following risk factors were found to be associated with conversion:surgical experience, history of abdominal surgery, male, obesity, tumor diameter≥6 cm, and tumor invasion or metastasis. Theseresults wereconsistent with those in the literature. A formula to predict the probability of conversion was created by logistic analysis on these clinical data. (where b1, b2.....b6=1 or 0 in the presence or absence of a particular risk factor)According to the results of multiple regression analysis and the coefficients of risk factors in the probability formula above,6,4,5,10,15, and 21 points were assigned to six variables, respectively, which included male gender, surgical experience (25 previous cases of laparoscopic rectectomy), history of abdominal surgery, BMI> 28, tumor diameter> 6 cm, and tumor invasion or metastasis.The conversion scores of 602 patients were determined based on the points assigned to each risk factor, and an ROC curve was obtained based on the scores and the presence/absence of conversion.The area under the curve was 0.876 with a standard error of 0.021. The optimal sensitivity and specificity were 0.861 and 0.786, respectively, at a score of 14.5. The conversion rate was 3.88% for patients with scores< 14.5 and 47.83% for patients with scores> 14.5, suggesting a significant difference between the two groups. Therefore, we established a scoring system to predict possible conversion of laparoscopic rectectomy. Preoperative evaluation was performed using the established scoring system on 50 patients who underwent laparoscopicrectectomy in our hospital from 2012 to 2014. Of a total of 48 patients with scores< 14.5, two required conversion (conversion rate=4.17%), while of two patients with scores> 14.5, both required conversion (conversion rate=100%), indicating a significant difference between groups.Conclusion:1、Our results demonstrated that male gender, surgical experience, history of abdominal surgery, BMI≥28, tumor diameter≥6 cm, and tumor invasion or metastasis were risk factors associated with conversion of laparoscopicrectectomy to open surgery.2、Unnecessary conversion may be effectively avoided by preoperative evaluation of each patient by the LRTO scoring system.3、With the continuous development of technologies, the influence of a history of abdominal surgery, tumor size, and tumor invasion was reduced, whereas the impact of surgical experience on conversion was relatively stable after surgeons obtained relatively rich experience with laparoscopic rectectomy. |
PDF Full Text Request