Learning curve for two-port video-assisted thoracoscopic surgery lung segmentectomy.

OBJECTIVES: When lung cancer evolves from a large, centrally located mass to small, peripherally located pulmonary nodules, such as ground glass nodules, segmentectomy offers a reasonable method by which to save lung parenchyma without eliciting compromising oncological effects. To master these techniques, it is important to analyse the learning curve of surgeons. Therefore, the aim of the present study was to analyse the learning curve for two-port video-assisted thoracoscopic surgery (VATS) segmentectomy in our institution. METHODS: We retrospectively collected data from 86 consecutive patients who underwent two-port VATS segmentectomy between June 2019 and November 2019. The operative time (OT) and estimated blood loss and other complications were analysed. The learning curve was evaluated using the OT and the cumulative sum (CUSUM) value of OTs across all cases. RESULTS: We generated a graph of the CUSUM of OTs and found that the learning curve could be differentiated into 3 phases: phase 1, the initial learning phase (1st to 27th operation); phase 2, the increased competence phase (28th to 54th operation); and phase 3, the experienced phase (55th to 86th operation). The CUSUM value inflected at patient number 47. There were significant reductions in the OT and bleeding in phase 3 relative to phases 1 and 2. There were also significant differences in OT and estimated blood loss between the simple and complex segmentectomy procedures. CONCLUSIONS: In conclusion, the 3 phases identified using CUSUM analysis of the OT represented characteristic stages of the learning curve for two-port VATS segmentectomy. The data indicate that, in our institution, the inflection point for the learning curve was achieved after operating on 47 cases.

Safety of early discharge with a chest tube after pulmonary segmentectomy.

OBJECTIVES: Early removal of chest tube is an important step in enhanced recovery after surgery protocols. However, after pulmonary resection with a wide dissection plane, such as pulmonary segmentectomy, prolonged air leak, a large volume of pleural drainage and the risk of developing empyema in patients can delay chest tube removal and result in a low rate of completion of the enhanced recovery after surgery protocol. In this study, we aimed to assess the safety of discharging patients with a chest tube after pulmonary segmentectomy. METHODS: We retrospectively reviewed a single surgeon's experience of pulmonary segmentectomy from May 2019 to September 2019. Patients who fulfilled the criteria for discharging with a chest tube were discharged and provided written instructions. They returned for chest tube removal after satisfactory resolution of air leak or fluid drainage. RESULTS: In total, 126 patients underwent pulmonary segmentectomy. Ninety-five (75%) patients were discharged with a chest tube postoperatively. The mean time to chest tube removal after discharge was 5.6 (range 2-32) days, potentially saving 532 inpatient hospital days. Overall, 90 (95%) patients experienced uneventful and successful outpatient chest tube management. No life-threatening complications were observed. No patient experienced complications resulting from chest tube malfunction. Five (5%) patients experienced minor complications. Overall, all patients reported good-to-excellent mobility with a chest tube. CONCLUSIONS: Successful postoperative outpatient chest tube management after pulmonary segmentectomy can be accomplished in selected patients without a major increase in morbidity or mortality.

A unique invertase is important for sugar absorption of an obligate biotrophic pathogen during infection.

An increased invertase activity in infected plant tissue has been observed in many plant-pathogen interactions. However, the origin of this increased invertase activity (plant and/or pathogen) is still under debate. In addition, the role of pathogen invertases in the infection process is also unclear. We identified and cloned a gene with homology to invertases from Puccinia striiformis f. sp. tritici (Pst). Transcript levels of PsINV were analyzed by quantitative reverse transcription PCR in both compatible and incompatible Pst-wheat interactions . Function of the gene product was confirmed by heterologous expression, and its function in Pst infection was analyzed by host-induced gene silencing (HIGS). Pst abundantly secretes invertase during its invasion attempts whether in a compatible or incompatible interaction with wheat. Further research into the different domains of this protein indicated that the rust-specific sequence contributes to a higher efficiency of sucrose hydrolysis. With PsINV silenced by HIGS during the infection process, growth of Pst is inhibited and conidial fructification incomplete. Finally, pathogenicity of Pst is impaired and spore yield significantly reduced. Our results clearly demonstrate that this Pst invertase plays a pivotal role in this plant-pathogen interaction probably by boosting sucrose hydrolysis to secure the pathogen's sugar absorption.