Primary spontaneous pneumothorax (PSP) is a very common clinical emergency, mostly seen in young men without other pulmonary comorbidities, and has the characteristics of recurrent attacks. Since the development of video-assisted thoracic surgery (VATS) in the 1990s, it has gradually become the first choice for the treatment of spontaneous pneumothorax because of its advantages of small trauma, no damage to chest wall muscles and nerves, good surgical effect, fast postoperative recovery and less pain. Television thoracoscopic surgery includes wedge resection of diseased lung tissue and pleural fixation to prevent recurrence. There is no uniform standard regarding the method of pleural fixation in clinical practice, which is mainly based on the surgeon’s custom. Pleural friction fixation is the most commonly used pleural fixation method in clinical practice, but there is little evidence that pleural friction fixation actually reduces the recurrence rate of primary spontaneous pneumothorax, and its necessity in PSP surgery needs to be further confirmed. The aim of this study was to analyze the role and necessity of pleural friction fixation in PSP surgery and to preliminarily investigate the causes of recurrence after PSP surgery and the associated risk factors. Huang Yuqing, Department of Thoracic Surgery, Beijing Haidian Hospital, Beijing, China From January 2010 to January 2013, cases eligible for enrollment in our center were subjected to different surgical interventions according to a simple randomized method (coin toss), i.e., wedge resection + pleural abrasion group (PA group) and simple wedge resection group (WR group). During the trial, it was found that test B was negative for the difference in recurrence rate; therefore, the results of test A were overridden by test B, which led to the early termination of the trial in the isolated herpes group at n=47 and the trial in the multiple herpes group at n=242. A total of 289 eligible cases were enrolled. No intraoperative or postoperative deaths or serious complications occurred in either group, and the mean follow-up was 18 months (6 to 30 months). 1. Results A total of 289 cases were enrolled in this study, including 144 cases in the wedge resection of the lung alone group (WR group) and 145 cases in the wedge resection + pleural friction fixation group (PA). There were no statistically significant differences in age, sex, pneumothorax site, smoking history, lesion location, herpes pattern and body mass index between the two groups. There were no intraoperative or postoperative fatal cases or serious complications in all enrolled patients. As shown in Table 2-1, there were no statistically significant differences in operative time, postoperative air leak time and hospital stay in all patients, but there were significant differences in intraoperative bleeding, postoperative 24 hours, 48 hours and total chest volume (p < 0.01), all of which were significantly lower in the wedge resection alone group (WR) than in the wedge resection + pleural friction fixation group (PA), with the postoperative time with tube slightly longer in the WR group than in the PA group (6.43±1.297 vs. 5.99±3.108). There were 21 patients with persistent postoperative air leak (>5 days) (including 13 patients with wedge resection alone), and the difference between the two groups was not statistically significant (p=0.181). All patients with persistent postoperative air leak healed on their own or by chemical pleural adhesion method (interleukin-2), and there were no cases of secondary surgery in the whole group. As shown in Table 3-2, for patients with multiple macrosomia, the differences in intraoperative bleeding, 24 hours, 48 hours postoperatively, and total chest drainage were significant (p < 0.01) and were all significantly lower in the wedge resection alone group (WR) than in the wedge resection + pleural friction fixation group (PA), consistent with the overall analysis of the whole group. The mean follow-up time after surgery was 18 months (6 to 30 months) in all cases. A total of 17 patients in the whole group had recurrence of postoperative pneumothorax, including 9 cases in the wedge resection group alone, with a recurrence rate of 6.3%, and 8 cases in the wedge resection + pleural friction fixation group, with a recurrence rate of 5.5% and an overall recurrence rate of 5.9%. The average follow-up time after surgery was 18 months (6 to 30 months) in all cases, and a total of 17 patients in the whole group had recurrence of postoperative pneumothorax (Table 3), including 9 cases in the wedge resection group alone, with a recurrence rate of 6.3%, and 8 cases in the wedge resection + pleural friction fixation group, with a recurrence rate of 5.5% and an overall recurrence rate of 5.9%, and the differences between the different herpetic forms and the overall recurrence rate in the two groups were not statistically There was no statistically significant difference between the two groups in terms of different maculoplasty patterns and overall recurrence rate. JS Park et al. found that low age, non-smoking, and multiple macules increased the risk of postoperative recurrence, while lesion site was not associated with postoperative recurrence, but the risk factors for postoperative recurrence of PSP are still controversial. Accordingly, we divided the factors that may affect the recurrence after PSP into exposed and non-exposed groups, as shown in Table 5, with age ≤20 or ≥30 years, male, body mass index ≤18, non-smoking, lesions including other sites besides the thoracic apex, and multiple macules as risk factors for the exposed group, and age between 20 and 30 years, female, body mass index >18, smoking, lesions located only in the thoracic apex, and The age, sex, body mass index, smoking history, lesion location, and herpes pattern were analyzed in relation to postoperative recurrence. Among them, low age (≤20 years) increased the risk of postoperative recurrence of PSP with a relative risk ratio (RR) of 3.015 (95% CI=1.092-8.324), whereas there were no cases of recurrence in the age ≥30 years group with a relative risk ratio of no postoperative recurrence compared to the exposed group, i.e., high age (≥30 years) mildly decreased the risk of postoperative recurrence (RR1.034. 1.004-1.065), and no other factors were significantly associated with the presence of postoperative recurrence. 2, Discussion Patients with primary spontaneous pneumothorax without other underlying lung disease occur mostly in lean, tall young men between 10 and 30 years of age, and rarely in those over 40 years of age. The recurrence rate of conservative treatment (observation, puncture aspiration, and closed chest drainage alone) is up to 30% or more, so surgery is needed to remove the diseased lung tissue and reduce its recurrence rate. With the application of thoracoscopic technology in clinical practice since the 1990s, it has basically replaced traditional open pulmonary herpetomy because of its advantages such as small trauma, no damage to chest wall muscles and nerves, good surgical effect, fast postoperative patient recovery and less pain, but there is no unified standard regarding the specific operation of thoracoscopic pulmonary herpetomy. Among the many surgical methods to prevent pneumothorax recurrence, mechanical pleural fixation as Among the many surgical methods to prevent recurrence of pneumothorax, mechanical pleural fixation is widely used as an adjunct technique to wedge resection of pulmonary herpes, which aims to create adhesions in the dirty wall layer of the pleura. The methods of mechanical pleural fixation include pleurodesis or pleural friction fixation, of which pleural friction fixation is widely used because of its relative simplicity and low risk. The goal of pleural fixation is to create extensive and tight adhesions to the dirty wall layer of the pleura, but these extensive and tight adhesions can lead to certain potential complications. These include postoperative chest discomfort, usually in the form of dull chest pain, postoperative bleeding or hemothorax, Horner syndrome, impaired pulmonary function, and fibrothorax, while adhesions formed by pleural friction add difficulty to possible future thoracic surgery. There is currently some controversy regarding postoperative chest discomfort after pleural adhesions. Lang-Lazdunski et al. reported a low incidence of postoperative chest pain after pleural friction fixation, but Horio et al. reported no significant difference in postoperative chest pain after pleural friction compared to simple pulmonary maculopexy, and these controversies may be attributed to the high subjectivity of the patient’s postoperative discomfort. Although pleural friction fixation is widely used in clinical practice, there are no uniform criteria regarding the extent and degree of friction and whether pleural friction is required in all PSP patients with different types of herpes, but rather depending on the surgeon’s practice. This study is the first prospective randomized controlled study to analyze the role of pleural friction fixation in PSP and to investigate the risk factors for postoperative recurrence in PSP patients, and to develop the optimal surgical practice for PSP, so that the advantages of VATS can be fully utilized and the efficacy of VATS for PSP can be significantly higher than that of conventional open chest, while the appropriate surgical method can be selected according to different types of herpes, so that This will have important theoretical value and clinical application significance for the treatment of PSP. In our research center, early PSP surgery was routinely performed by wedge resection + pleural friction fixation, and the wall pleura was carefully rubbed by electric knife rubbing until extensive and uniform bleeding spots appeared in the rubbing area, and the rubbing range was up to the top of the chest and down to the sixth intercostal space, which was basically consistent with the internationally reported rubbing range and degree, even so, the adhesions produced after pleural rubbing were still quite limited, and the recurrence rate was still between 0% and 10%. In patients undergoing secondary surgery, we found that the main cause of recurrence was the formation of neonatal herpes, especially at the surgical margins. In addition, these pleural adhesions are either localized or extensive in patients undergoing pleural friction fixation, however, in most recurrent cases these adhesions are not strong enough to prevent pneumothorax recurrence and tearing of the trophoblastic vessels in the adhesion zone due to secondary pneumothorax can lead to severe hemopneumothorax or even life-threatening. In addition, these incomplete adhesions conceal the new herpes during secondary surgery and increase the risk of lung parenchymal injury during adhesiolysis. Based on the above, we have been studying the need for pleural friction fixation since 2010, and we have focused our surgical efforts on careful observation of possible pulmonary herpes and precise excision of the herpetic tissue found. Special emphasis was placed on the examination of the normal lung parenchyma at the cut edge to avoid missing potential future weak points for the formation of pulmonary blisters. We believe it is more important to prevent pneumothorax by proactively optimizing the surgical procedure and selecting different procedures for patients with different types of pulmonary blisters than by passively preventing pneumothorax through pleural adhesions, especially in patients with isolated limited pulmonary blisters. In this study, although the overall postoperative recurrence rate was slightly higher in the wedge resection-only group than in the pleural friction fixation group (6.3% vs. 5.5%), we found that the recurrence cases were mostly early cases since the study was conducted, and we attributed this difference to the careful intraoperative observation of the underlying diseased lung tissue, while statistical analysis revealed no statistical difference between the recurrence rate in the wedge resection-only and pleural friction fixation groups (p=0.7). (p=0.791), and the recurrence rates in both groups were within the range of internationally reported pneumothorax recurrence rates. Moreover, the recurrent cases in the wedge resection group alone were more likely to be found in the secondary surgery than after pleural friction fixation, which reduced the surgical difficulty of the secondary surgery for pneumothorax recurrence. Meanwhile, from the intraoperative and postoperative results, there were no statistically significant differences between the two groups in terms of operative time, postoperative air leakage time and hospital stay, but there were significant differences in intraoperative bleeding, postoperative 24 hours, 48 hours and total chest volume, all of which were significantly lower in the wedge resection alone group (WR) than in the wedge resection + pleural friction fixation group (PA); and the postoperative tube banding time was slightly longer in the WR group than in the PA group. Further analysis of the recurrence cases in Table 4 showed that recurrence in both groups occurred mostly at an early stage (within 3 weeks), but the majority of patients with recurrence in the WR group were cured by symptomatic conservative treatment such as observation and rest, and the patients had milder symptoms, whereas there was no pattern in the postoperative management of the PA group, and we observed the formation of new herpes in all three patients who underwent secondary surgery in the PA group. Accordingly, we hypothesized that the early recurrence in the simple wedge resection group might be related to the air leakage from the needle eye of the cutting edge suture, which could heal on its own after a period of time, rather than due to the rupture of the new herpes. This further suggests that wedge resection alone is sufficient to prevent pneumothorax recurrence, especially in patients with isolated limited pulmonary herpes, and that additional pleural friction fixation is questionable because of the unnecessary physiological and economic costs to the patient. Many research institutions have proposed new techniques and approaches in the optimization of PSP surgical techniques. Seokkee Lee et al. compared the effects of pleural friction fixation and cut edge covered absorbable polyglycolic acid resin (PGA) patches and found that PGA patches were effective in reducing postoperative air leak time and preventing recurrence. Minocycline as a chemical pleural adhesion method has also been shown to be effective in preventing pneumothorax recurrence. An analysis of risk factors for postoperative recurrence of PSP revealed that patient gender, body mass index, lesion site, macular pattern, and whether or not they smoked were not associated with postoperative recurrence, whereas low age (≤20 years) increased the risk of postoperative recurrence of PSP.JS Park et al. reported similar results and found that low age and non-smoking were risk factors for postoperative recurrence of PSP, whereas Cheng et al. concluded that smoking significantly increased the postoperative recurrence rate of patients with primary spontaneous pneumothorax, and there is still some controversy about the risk factors for postoperative recurrence in patients. In conclusion, this study demonstrated that thoracoscopic wedge resection of pulmonary bullae alone is sufficient to control postoperative recurrence of primary spontaneous pneumothorax, and additional pleural friction fixation brings unnecessary injury to the patient, and the surgical approach of primary spontaneous pneumothorax needs to be further standardized and optimized.