Electromagnetic navigation bronchoscopy (ENB) has been widely used to mark small peripheral pulmonary nodules (PPNs) in video-assisted thoracic surgery (VATS) resection. This technique offers the advantages of a high accuracy and fewer complications. However, few studies have analyzed the learning curve of ENB-guided preoperative localization. We aimed to describe the learning curve and factors influencing ENB-guided thoracoscopic pulmonary nodule resection.

This study included 300 consecutive patients with PPNs who underwent ENB-guided localization by the same endoscopist in our department between November 2019 and December 2021. The cumulative sum (CUSUM) method was used to analyze the learning curve of ENB-guided localization and the learning curve in different lobes, while logistic regression was used to analyze the risk factors affecting ENB operative time (OT).

In 184 patients with 300 nodules, three learning phases were identified through turning points of the learning curve: Phase I (the 16th nodule), Phase II (the 17th to the 107th nodule), and Phase III (the 107th to the 300th nodule). No significant difference was found in the success rate of ENB-guided localization in each phase of the learning curve (100%, 96.7%, and 97.9%, P=0.78). The distance from the localization to the pleura in Phase I was statistically significantly shorter than that in Phase II and Phase III (0.6±0.4 vs. 1.1±0.6 vs. 1.0±0.5 cm, P=0.001 and P=0.003). Furthermore, the learning curves for nodules in different lobes were different. The learning curve for the upper lobe nodules was divided into two phases; the learning curve for the middle lobe disclosed more negative values; and the learning curve for the lower lobe nodules displayed no obvious pattern. Significant differences were found in nodule location, distance from the localization to the pleura and learning curve phase (P=0.003, P<0.001, P=0.02). The independent factors for OT included gender, smoking history, nodule type, distance from localization to the pleura, and learning curve phase.

ENB OT at the 107th nodule leveled off and showed a downward trend. Different lobes have different learning curves, the middle lobe is the easiest lobe to learn with ENB and can be used as the first lobe of choice for beginners. The learning curve can objectively evaluate the accuracy of ENB location and help endoscopists identify areas for improvement.

ObjectiveTo evaluate the value and clinical effect of different preoperative localization techniques for solitary pulmonary nodules (SPN) before single-port thoracoscopic surgery.MethodFrom January 2018 to June 2019, 54 patients diagnosed with solitary pulmonary nodules received single-port thoracoscopic surgery in Thoracic Department of General Hospital of Southern Theater Command of PLA. Based on the location methods of the nodules, the patients were divided into group A (34 cases) with preoperative CT-guided Hook-wire (a common positioning needle usually using in mammary gland) positioning and group B (20 cases) with preoperative CT-guided methylene blue location.ResultsThe success rate of localization in group A was 94.18% (32/34), significantly higher than that in group B [85% (17/20), P < 0.05). No intraoperative conversion to thoracotomy occurred in group A, while the conversion rate was 10% (2/20) in group B (P < 0.05). The average positioning cost was significantly higher in group A than in group B (1715±109 vs 1021±86 RMB yuan, P < 0.05), but the total hospitalization cost was similar between the two groups (50 114±3788 vs 47871±5902 RMB yuan, P>0.05). The length of hospital stay was significantly shorter in group A than in group B (6.71±1.23 vs 8.19±2.61 days, P < 0.05).ConclusionCompared with the traditional methylene blue localization method, Hook-wire localization positioning can significantly increase the success rate of localization, and can be used as the standard preoperative localization method in patients undergoing single-port thoracoscopic pulmonary nodule resection, especially in those with deep nodule location from the visceral pleura.