ObjectiveTo monitor surgical quality and analyze learning curve of minimally invasive mitral valve replacement (MVR)through right minithoracotomy with cumulative sum analysis (CUSUM analysis). MethodsClinical data of 60 consecutive patients who underwent minimally invasive MVR through right minithoracotomy in the Fourth Affiliated Hospital of Guangxi Medical University from June 2011 to April 2013 were retrospectively analyzed. There were 32 male and 28 female patients with their age of 28-53 (34.67±7.11)years and their heart function ranging from NYHA class Ⅱ to Ⅳ. There were 31 patients with mitral stenosis (MS), 19 patients with mitral regurgitation (MR), and 10 patients with MS and MR. According to the surgical sequence, all the patients were divided into 3 groups (group A, B and C)with 20 patients in each group. Surgical outcomes were compared among the 3 groups, and surgical quality was analyzed with descriptive statistics and CUSUM curves. ResultsAortic cross-clamp time, cardiopulmonary bypass time and operation time of group C were significantly shorter than those of group A and group B (aortic cross-clamp time of group C vs. group A:50.35±2.30 minutes vs. 66.15±8.38 minutes; operation time of group C vs. group B:167.50±4.63 minutes vs. 178.60±4.49 minutes, P < 0.05). In-hospital mortality was 3.3% (2/60). CUSUM analysis showed a significant learning curve effect, although surgical quality remained in control during the study period. Surgical failure rate was lower than 80% after about 45 operations, indicating that failure rate was 10% lower than expectation. ConclusionMinimally invasive MVR is safe and reliable, and CUSUM analysis is a simple statistical method to monitor surgical quality.
ObjectiveTo explore the learning curve of endoscopic thyroidectomy using the gasless unilateral axillary approach for papillary thyroid microcarcinoma.MethodsWe retrospectively analyzed the clinical data of 51 patients diagnosed with papillary thyroid microcarcinoma who underwent an endoscopic thyroidectomy using a gasless unilateral axillary approach by the same surgeon from November 2019 to September 2020 in the Department of Thyroid and Parathyroid Surgery, West China Hospital, Sichuan University. The cumulative sum (CUSUM) analysis was used to determine the learning curve of the technology, and the CUSUM learning curve was modeled by the best fit. The operative time, intraoperative blood loss, number of lymph nodes dissected, incidence of complications and postoperative hospital stay in different phases of the learning curve were compared.ResultsThe CUSUM fitting curve reached the top at the 18th case. As a cut-off point, the learning curve was divided into two stages: the learning improvement period and the proficiency period. The operative time of patients in the proficiency stage was significantly shorter than that in the learning improvement stage (P<0.05), and there were no statistically significant differences in other data of patients in the two stages (P>0.05).ConclusionThe CUSUM analysis method is used to accurately analyze the learning curve of endoscopic thyroidectomy using the gasless unilateral axillary approach for papillary thyroid microcarcinoma, indicating that the cumulative number of operations required to master this technique is 18 cases.
Objective To explore the clinical efficacy and learning curve of robot-assisted thymectomy via subxiphoid approach. MethodsThe clinical data of patients with robot-assisted thymectomy surgery via subxiphoid approach performed by the same surgical team in the Department of Thoracic Surgery of Shanghai Pulmonary Hospital from February 2021 to August 2022 were retrospectively analyzed. The cumulative sum (CUSUM) analysis and best fit curve were used to analyze the learning curve of this surgery. The general information and perioperative indicators of patients at different learning stages were compared to explore the impact of different learning stages on clinical efficacy of patients. ResultsA total of 67 patients were enrolled, including 31 males and 36 females, aged 57.10 (54.60, 59.60) years. The operation time was 117.00 (87.00, 150.00) min. The best fitting equation of CUSUM learning curve was y=0.021 2x3–3.192 5x2 +120.17x–84.444 (x was the number of surgical cases), which had a high R2 value of 0.977 8, and the fitting curve reached the top at the 25th case. Based on this, the learning curve was divided into a learning period and a proficiency period. The operation time and intraoperative blood loss in the proficiency stage were significantly shorter or less than those in the learning stage (P＜0.001), and there was no statistical difference in thoracic drainage time and volume between the two stages (P＞0.05). ConclusionThe learning process of robot-assisted thymectomy via subxiphoid approach is safe, and this technique can be skillfully mastered after 25 cases.
ObjectiveTo analyze the learning curve of Da Vinci robotic segmentectomy. MethodsCumulative sum analysis (CUSUM) was used to analyze the learning curve of Da Vinci robotic segmentectomy performed by the General Hospital of Northern Theater Command from February 2018 to December 2020. The learning curve was obtained by fitting, and R2 was used to judge the goodness of fitting. The clinical data of patients in different stages of learning curve were compared and analyzed. Results The first 50 patients who received Da Vinci robotic segmentectomy were included, including 24 males and 26 females, with an average age of 61.9±10.6 years. The operation time decreased gradually with the accumulation of operation patients. The goodness of fitting coefficient reached the maximum value when R2=0.907 (P<0.001), CUSUM (n) =0.009×n3−0.953×n2+24.968×n−7.033 (n was the number of patients). The fitting curve achieved vertex crossing when the number of patients reached 17. Based on this, 50 patients were divided into two stages: a learning and improving stage and a mastering stage. There were statistical differences in the operation time, intraoperative blood loss, postoperative drainage volume, number of lymph node dissection, postoperative catheter time, postoperative hospital stay, and postoperative complications between the two stages (P<0.05). ConclusionIt shows that the technical competency for assuring feasible perioperative outcomes can be achieved when the cumulative number of surgical patients reaches 17.
ObjectivesTo evaluate the learning curve of radical hepatectomy combined with vascular and/or bile duct reconstruction (RHVBR) in the treatment of hepatic alveolar echinococcosis (HAE), and to explore the feasibility and safety of RHVBR. MethodsThe clinical data of 203 patients who received RHVBR treatment for HAE complicated with vascular invasion in West China Hospital from 2010 to 2018 were analyzed retrospectively. Cumulative sum (CUSUM) and risk-adjusted cumulative sum (RA-CUSUM) were used to analyze the learning curve of RHVBR, determine the learning stage, and compare the differences of intraoperative and postoperative outcome indexes in different learning stages. ResultsThe average operative time was (537.9±207.6) minutes, with an average blood loss amounted to (616.5±724.7) mL. Postoperative complications occurred in 65 cases, and the incidence of complications was 32.0%. Among them, 29 cases (14.3%) had serious complications. Three cases (1.5%) died within 90 days after operation. The results of RA-CUSUM analysis showed that 54 cases of surgery were the cut-off point of learning curve for serious postoperative complications. According to the results of CUSUM analysis, the whole queue was divided into the first stage (n=53) and the second stage (n=150) based on the completion of 53 operations. Compared with the first stage, the operative time and total postoperative hospital stay in the second stage were shortened, the incidence of serious complications was reduced, and the number of resected liver segments was increased. The differences were statistically significant (P<0.05). ConclusionIt is feasible and safe to treat HAE with RHVBR, and the incidence of serious complications is obviously reduced after 54 cases of operation.