Current situation of management of spontaneous pneumothorax in Japan: A cross-sectional cohort study.

BACKGROUND: Limited epidemiological information is available on spontaneous pneumothorax. To address this gap, the Japan Society for Pneumothorax and Cystic Lung Disease (JSPCLD) conducted a nationwide retrospective survey to investigate the current epidemiology of spontaneous pneumothorax in Japan. METHODS: In this study, we conducted a retrospective cross-sectional cohort study to demonstrate the clinical features of spontaneous pneumothorax in one year from April 2019 to March 2020, compare patient characteristics and treatment outcomes between primary (PSP) and secondary spontaneous pneumothorax (SSP), and investigate the risk factors associated with in-hospital mortality among patients with SSP. RESULTS: A total of 1784 patients from 28 institutions were enrolled in the study, with PSP observed in 956 cases (53.6%) and SSP in 817 cases (45.8%). The age distribution showed a biphasic peak caused by the different peaks between PSP and SSP. In-hospital mortality occurred in 42 cases (2.4%) among all patients, with 0 cases (0%) in PSP and 42 cases (5.1%) in SSP. Multivariable analyses revealed that interstitial pneumonia as an underlying disease (odds ratio: 2.4700, 95% confidence interval: 1.1100 to 5.4800, p = 0.0269), performance status≧3 (odds ratio: 7.3900, 95% confidence interval: 3.1900 to 17.2000, p < 0.0001), and lower value of serum albumin on admission (odds ratio: 0.4060, 95% confidence interval: 0.2140 to 0.7690, p = 0.0057) were significantly associated with in-hospital mortality among patients with SSP. CONCLUSIONS: SSP patients with poor baseline conditions are at a higher risk for in-hospital mortality. It is crucial to provide close and meticulous management for SSP patients with compromised conditions.

Postoperative hormonal therapies reduce the recurrence of thoracic endometriosis-related pneumothorax.

OBJECTIVES: Thoracic endometriosis-related pneumothorax (TERP) frequently recurs even after surgery. Meanwhile, postoperative hormonal therapies (HTx) are believed to be effective for pelvic endometriosis. Therefore, we evaluated the relationship between postoperative TERP recurrence and postoperative HTx in a retrospective observational study. METHODS: We retrospectively reviewed the data of patients with TERP who underwent the first video-assisted thoracoscopic surgery between January 2011 and February 2022. RESULTS: Of the 248 patients eligible for this study, 67 (27.0%) experienced postoperative TERP recurrence. Postoperative HTx were administered to 70 patients (28.2%). Dienogest was the most frequently administered drug, given to 56.7% of patients. Following univariable analysis, postoperative hormonal therapies was closely related to reduce postoperative recurrence (P = 0.003). Likewise, the multivariable analysis revealed postoperative hormonal therapies were significantly associated with the risk reduction of recurrence (hazard ratio 0.28, P < 0.001). CONCLUSIONS: Postoperative HTx reduced TERP recurrence. We hypothesize that HTx may control residual endometrial tissues to avoid TERP if pleural endometrial tissues are resected as much as possible.

Clinicopathological Impacts of Expression of Neuronal Markers in Lymphangioleiomyomatosis.

Lymphangioleiomyomatosis (LAM) is a tuberous sclerosis complex (TSC)-associated tumor, characterized by the expression of neural crest lineages including neuronal markers. Neural crest cells can differentiate into multiple cell types that contribute to tissues associated with TSC-related tumors, and TSC-related tumors could be specifically associated with distinct neural crest subtypes. This study aimed to clarify the clinicopathological effects of expression of neuronal markers in LAM. Lung tissues from 40 patients with LAM (of whom 13, 1, and 26 had undergone lung transplantation, lobectomy, and partial lung resection, respectively) were immunohistochemically analyzed. All patients were women, and their median age was 36 years (range: 24-62 y). All patients who underwent lung transplantation or lobectomy were classified as LAM histologic score (LHS)-3, whereas those who underwent partial lung resection were classified as LHS-1. LAM cells expressed peripherin (65%), and neuron-specific ßIII-tubulin (43%). A comparison of the early (LHS-1) and advanced (LHS-3) stages of LAM revealed that neuron-specific ßIII-tubulin was significantly expressed in the early stage of LAM ( P = 0.0009). Neuron-specific ßIII-tubulin-positive LAM was associated with younger age ( P < 0.0001), the coexistence of renal angiomyolipoma ( P = 0.027), and the absence of retroperitoneal LAM ( P = 0.045). Furthermore, based on the expression levels of immunohistochemical markers in LAM, 2 distinct clusters with different expression levels of neuronal markers were observed. Approximately 40% to 60% of patients with LAM expressed neuron-specific ßIII-tubulin and peripherin. Neuronal expression may be associated with disease severity.

Clinical and genetic features of 334 Asian patients with Birt-Hogg-Dubé syndrome (BHDS) who presented with pulmonary cysts with or without a history of pneumothorax, with special reference to BHDS-associated pneumothorax.

BACKGROUND: The clinical pulmonary manifestations and genetic features of Birt-Hogg-Dubé syndrome (BHDS) in Asian patients remained unclear. We aimed to clarify the clinical features of BHDS-associated pneumothorax (PTX) and retrospectively investigate potential contributing factors in the largest Asian cohort to date. METHODS: We reviewed the clinical and genetic data collected in 2006-2017, from the BHDS patients who were Asian and presented with pulmonary cysts with or without a history of PTX. RESULTS: Data from 334 (41.3% males; 58.7% females) patients from 297 unrelated families were reviewed. Among them, 314 (94.0%) patients developed PTX. The median age at the first occurrence of PTX was 32 years, which was significantly lower in males (P = 0.003) and patients without notable skin manifestations (P < 0.001). Seventy-six (24.2%) patients experienced their first PTX episode before the age of 25 years. PTX simultaneously occurred in the bilateral lungs of 37 (11.8%) patients. Among 149 patients who had their first PTX episode at least 10 years before BHDS diagnosis, PTX occurred more frequently in males (P = 0.030) and light smokers than in nonsmokers (P = 0.014). The occurrence of PTX peaked in the early 30s and gradually decreased with age but remained high in females (P = 0.001). We identified 70 unique FLCN germline variants, including duplications (46.4%), substitutions (7.1%), insertions/deletions (30.0%), and variants affecting splicing (12.5%). Approximately 80% of Asian patients suspected of having BHDS could be genetically diagnosed by examining FLCN exons 7, 9, 11, 12, and 13. No apparent genotype-phenotype correlation regarding pulmonary manifestations was identified. CONCLUSIONS: Our findings indicate that sex, smoking history, and skin manifestations at BHDS diagnosis significantly influence the clinical features of BHDS-associated PTX. These findings may contribute to the appropriate management and treatment of BHDS-associated PTX.

Dynamics of thoracic endometriosis in the pleural cavity.

BACKGROUND: Thoracic endometriosis-related pneumothorax is a secondary spontaneous pneumothorax caused by thoracic endometriosis. Diaphragmatic endometriosis is well-studied, but visceral and/or parietal pleural lesions are not. Although surgery is an effective treatment, postoperative recurrence rates are unsatisfactory probably due to inadequate understanding of underlying pathophysiology. We aimed to clarify the clinicopathological features of thoracic endometriosis. METHODS: In total, 160 patients who underwent thoracoscopic surgery from a single institution with histopathologically proven thoracic endometriosis from January 2015 to December 2019 were included. Clinicopathological characteristics and surgical outcomes were assessed retrospectively. RESULTS: The cohort median age was 41 (range 22-53) years. Pneumothorax was right-sided in 159 (99.4%) and left-sided in only 1 (0.6%) case. Visceral and parietal pleural lesions were diagnosed in 79 (49.4%) and 71 (44.4%) patients, respectively. In total, 104 visceral pleural lesions and 101 parietal pleural lesions were detected. The S4 region and the dorsal 6th intercostal space contained the largest number of visceral pleural (66 lesions) and parietal pleural lesions (25 lesions), respectively. Histopathological evaluation revealed endometriotic tissues, existing in the outer external elastic layer in all lesions, were localized or invaded deeply. The median follow-up period was 370 (range, 6-1824) days. The Kaplan-Meier method revealed that the 1- and 2-year postoperative recurrence rates were 13.8% and 19.3%, respectively. CONCLUSIONS: Visceral pleural endometriotic lesions may be disseminated from the visceral pleural surface and infiltrate into the pleura. Intraoperatively, careful observation of the specific sites, such as the visceral pleura of S4 and the parietal pleura of 6th intercostal space, is important to reduce postoperative recurrence.

Current opinion and comparison of surgical procedures for the treatment of primary spontaneous pneumothorax.

INTRODUCTION: Although three-port video-assisted thoracoscopic surgery (VATS) is the standard radical treatment for primary spontaneous pneumothorax (PSP), several issues need to be addressed as the postoperative recurrence rate remains relatively high. Although bullectomy is effective in preventing the postoperative recurrence of PSP, recurrent pneumothorax often occurs, requiring additional methods such as pleural covering with absorbable mesh sheets, surgical chemical pleurodesis, pleural abrasion, or pleurectomy. In addition, minimally invasive approaches that exceed three-port VATS are required according to the social demand. These approaches, such as uniportal VATS, reduced port surgery, and needlescopic surgery, have cosmetic merits, lower postoperative pain, and similar surgical results as three-port VATS. AREAS COVERED: We focused on conventional and novel treatments for PSP in this article. EXPERT OPINION: Effective methods that prevent postoperative recurrence and minimally invasive approaches will become popular in the near future.

The effects of total pleural covering on pneumothorax recurrence and pulmonary function in lymphangioleiomyomatosis patients without history of pleurodesis or thoracic surgeries for pneumothorax.

BACKGROUND: Total pleural covering (TPC) is an innovative surgical procedure in which the entire visceral pleura is wrapped with sheets of oxidized regenerated cellulose (ORC) mesh under video-assisted thoracoscopic surgery. We have previously reported that TPC could successfully prevent pneumothorax recurrence in patients with lymphangioleiomyomatosis (LAM). However, the actual efficacy and preventive effect of TPC on pneumothorax recurrence remains unclear as many LAM patients already had pleural adhesion prior to TPC that was induced by thoracic surgery and/or pleurodesis. The purpose of this study is to evaluate the effects of TPC on pneumothorax recurrence and pulmonary function in LAM patients with no history of thoracic surgeries or pleurodesis. METHODS: We retrospectively reviewed medical charts of 52 patients (60 hemithoraces) who underwent TPC at our center, from January 2003 to September 2019, as a first surgical intervention for pneumothorax. RESULTS: Pneumothorax recurrence occurred in 12 patients [14 of 60 hemithoraces (23.3%)] during the observation period [27 months (14.7; 56.4) = median (lower; upper quartiles)]. The probability of recurrence-free hemithorax post TPC was 81.1% at 2.5 years and 64.1% at 5 years. TPC did not produce a significant decrease in either VC %predicted (pred) or FEV1/FVC. The pre- vs. post-TPC median (lower; upper quartiles) VC %pred was 85.7% (79.7; 98.0) vs. 87.2% (72.3; 95.6), P=0.535 and the FEV1/FVC was 84.6% (75.7; 89.6) vs. 83.0% (71.8; 87.0), P=0.667. Mechanistic/mammalian target of rapamycin (mTOR) inhibitors (mTORI) were subsequently initiated in 19 patients (36.5%) because of the progression of LAM. The postoperative FEV1%pred was significantly lower in patients who required mTORI than in those who did not [68.1% (57.3; 82.9) vs. 88.7% (84.6; 89.8), P=0.020]; the decline rate in FEV1%pred/year from pre to post TPC was significantly greater in LAM patients who required mTORI than in those who did not [-9.37% (-4.73; 12.9) vs. -1.94% (1.52; -4.50), P=0.029]. Postoperative complications were found in 25 of 52 hemithoraces (48.1%). CONCLUSIONS: TPC can prevent pneumothorax recurrence without causing ventilatory impairment or severe pleural symphysis in LAM patients. TPC is an effective treatment option for LAM-associated pneumothorax based on its efficacy and safety.

Is conventional management of primary spontaneous pneumothorax appropriate?

OBJECTIVE: This study aimed to evaluate the recurrence rate after primary and secondary conservative treatments and to clarify the validity of current primary spontaneous pneumothorax management by comparing secondary conservative treatment and surgical outcomes. METHODS: Data from 166 patients with primary spontaneous pneumothorax treated at a single site between September 2015 and March 2019 were retrospectively evaluated. Patient characteristics of those who received primary conservative therapy (n = 166) and secondary conservative therapy (n = 28) were summarized. The outcomes from patients who experienced recurrence (n = 64) were compared based on those who underwent surgery (n = 24) and those who underwent secondary conservative therapy (n = 28). RESULTS: The post-treatment day 60 recurrence rate was 27.1 and 49.5% cases in the primary and secondary treatment groups, respectively, which was significantly higher after secondary treatment than after primary treatment with conservative therapy (p = 0.032). The post-treatment one-year recurrence rate was 13.5 and 57.9% in patients who underwent surgery and secondary conservative treatment, respectively; secondary conservative treatment resulted in a significantly higher recurrence rate than surgery (p < 0.001). CONCLUSIONS: There is evidence for guidelines that recommend surgery for recurrent primary spontaneous pneumothorax after primary conservative therapy based on its lower and more delayed post-treatment recurrence rate than secondary treatment with conservative therapy.

Does a gender have something to do with clinical pictures of primary spontaneous pneumothorax?

OBJECTIVE: Primary spontaneous pneumothorax is relatively rarer in women than in men. In addition, women develop secondary spontaneous pneumothorax, such as lymphangioleiomyomatosis, which is rare and difficult to diagnose. Therefore, the clinical characteristics of primary spontaneous pneumothorax in women remain unknown presently. We compared the clinical characteristics of primary spontaneous pneumothorax between the two sexes at two pneumothorax centers. METHODS: Between January 2015 and July 2019, we retrospectively evaluated 627 cases (106 women and 521 men) who underwent first video-assisted thoracoscopic surgery for primary spontaneous pneumothorax and extracted the medical backgrounds and postoperative recurrence between the sexes. Univariate and multivariate analysis was used to examine the effect of sexual specificity on postoperative recurrence. RESULTS: Among women and men with PSP, the mean ages were 27.8 ± 10.7 and 24.3 ± 10.0 years, respectively; their mean heights were 162.0 ± 5.9 and 173.3 ± 6.1 cm, respectively. These differences were statistically significant. Three women (2.8%) and 54 men (10.4%) developed postoperative recurrence, which showed significant difference on Kaplan-Meier analysis (p = 0.027). Univariate and multivariate analysis showed the factors; women (p = 0.045, hazard ratio: 0.289 [95% confidence interval 0.086-0.973]) and smoker (p = 0.035, hazard ratio: 0.269 [95% confidence interval 0.079-0.909]) had the preventing factor for postoperative recurrence, respectively. CONCLUSIONS: Women with PSP had lower postoperative recurrence rate than men. Although we could not reveal why women had lower postoperative recurrence rates than men in this study, the sexual difference such as hormonal cycle, development of body structure possibly affects the clinical characteristics of women with primary spontaneous pneumothorax.

The clinical characteristics and surgical results of smoking-related young pneumothorax.

OBJECTIVE: Primary spontaneous pneumothorax is a common disease that develops in relatively young healthy patients. Although smoking is generally believed to have a negative effect on the lungs, some authors reported that smokers with primary spontaneous pneumothorax had significantly lower postoperative recurrence rates than nonsmokers. This unexpected result suggests that primary spontaneous pneumothorax is classified into two categories: smoking-related young pneumothorax and residual primary spontaneous pneumothorax. We compared these two categories to determine their characteristics and corresponding surgical results. METHODS: Between January 2009 and December 2018, we enrolled 267 consecutive cases that underwent first surgery for primary spontaneous pneumothorax in our hospital. A total of 252 eligible cases (211 residual primary spontaneous pneumothorax and 41 smoking-related young pneumothorax) underwent evaluation. Smoking-related young pneumothorax cases were defined as cases with characteristic HRCT findings and smoking habit. RESULTS: The mean ages for the residual primary spontaneous pneumothorax and smoking-related young pneumothorax groups were 25.9 ± 13.1 and 30.5 ± 6.9 years, respectively. The groups included 186 (88.2%) and 41 (100.0%) men, and the mean body mass indices were 19.1 ± 2.2 and 20.0 ± 1.9, respectively. Fifty-nine (28.0%) and 41 (100.0%) subjects were smokers, and there were 43 (20.4%) and 1 (2.4%) cases of postoperative recurrence, respectively. These results were significantly different between the two groups. CONCLUSIONS: Individuals with smoking-related young pneumothorax were older, predominantly men, and had higher body mass index and significantly lower postoperative recurrence rates than those with residual primary spontaneous pneumothorax.

Optimal margin distance of bullectomy for primary spontaneous pneumothorax reduces postoperative recurrence.

BACKGROUND: For primary spontaneous pneumothorax, bullectomy using autosutures is the standard procedure. Despite performing various methods for preventing postoperative recurrence, it remains relatively high. Although considering the margin distance of bullectomy is important, no argument has been discussed for the optical margin distance until now. Hence, we evaluated the optimal margin distance for bullectomy of spontaneous pneumothorax, bullectomy to reduce postoperative recurrence. METHODS: Between March 2015 and May 2018, 91 eligible candidates from 142 cases, who underwent video-assisted thoracoscopic bullectomy for spontaneous pneumothorax, bullectomy, were evaluated. We analysed the factors preventing postoperative recurrence, including the margin distance using the inverse-probability of treatment weighted method by propensity score was used to adjust for heterogeneous patient backgrounds. RESULTS: The patients' median age was 20 years (range, 14-86 years). Postoperative recurrences occurred in 8 cases (8.8%). The margin distance was 9.1±5.0 mm. The cut-off point of the margin distance was defined as 5.0 mm. The inverse-probability of treatment weighted method indicated that a margin distance ≥5.0 mm significantly prevented postoperative recurrence (P=0.0076, hazard ratio =0.18). CONCLUSIONS: This study suggests that a margin distance of ≥5.0 mm for bullectomy of PSP can reduce postoperative recurrence.

Contralateral bulla neogenesis associated with postoperative recurrences of primary spontaneous pneumothorax in young patients.

BACKGROUND: Video-assisted thoracoscopic surgery (VATS) is considered an acceptable treatment for recurrent primary spontaneous pneumothorax (PSP). However, recent reports have described a high postoperative recurrence rate in young patients with PSP. We hypothesized that ineffective VATS may have been performed for these patients (aged <25 years). We evaluated the factors preventing postoperative recurrence in young PSP patients in order to identify patients with effective surgery. METHODS: Between April 2009 and December 2018, we retrospectively evaluated 92 patients aged <25 years who underwent first VATS bullectomy for PSP. Factors such as gender, smoking habit, history of contralateral PSP, family history, body mass index (BMI), and contralateral bulla neogenesis on high-resolution computed tomography were evaluated. RESULTS: The mean BMI was 18.8±1.8. Contralateral bulla neogenesis was present in 31 patients (33.7%). The median period of observation for postoperative recurrence was 401.5 days. Thirty cases (32.6%) developed postoperative recurrence. Univariate and multivariable analyses showed that a BMI ≥18.0 and no contralateral bulla neogenesis were significant factors preventing postoperative recurrence (P=0.018, hazard ratio: 0.41 and P=0.0046, hazard ratio: 0.25, respectively). CONCLUSIONS: Although the patients aged <25 years have a high rate of postoperative recurrence, the patients with BMI ≥18.0 and no contralateral bulla neogenesis have a significantly lower rate of postoperative recurrence rate.

Natural history of bulla neogenesis for primary spontaneous pneumothorax: a propensity score analysis.

OBJECTIVE: For patients with recurrent primary spontaneous pneumothorax, surgery has been thought to be an acceptable treatment. However, even if bulla is completely resected, postoperative recurrence is relatively common due to bulla neogenesis. Bulla neogenesis seems to develop naturally in younger patients compared with the elderly, as theorized till date. If the complete development of bulla neogenesis is confirmed, surgical resection can be performed as the radical treatment. Then, we evaluated the relationship between bulla neogenesis and age. METHODS: Between February 2009 and July 2018, we consecutively enrolled 276 patients who underwent primary bullectomy for primary spontaneous pneumothorax in our hospital. Finally, high-resolution computed tomography findings/observations of 155 eligible patients were evaluated retrospectively. The relationship between bulla neogenesis and age was evaluated using univariate and multivariate analyses and an inverse probability of treatment-weighted method using the propensity score. RESULTS: The study included 58 patients aged < 20 years and 97 aged ≥ 20 years. Bulla neogenesis was present in 34 patients (21.9%). Bulla neogenesis developed significantly at age < 20 compared with age ≥ 20 (44.8 vs. 8.2%). Univariate and multivariate analyses showed that age < 20 years was a significant factor associated with bulla neogenesis (P < 0.001 and P = 0.018, respectively). The inverse probability of treatment-weighted method showed that age < 20 years was a significant factor associated with bulla neogenesis (P = 0.0057, hazard ratio 4.79). CONCLUSIONS: Surgical treatment may be delayed in young patients (age < 20 years), because bulla neogenesis is not completely developed by this time for primary spontaneous pneumothorax.

Pleural Coating by 50% Glucose Solution Reduces Postoperative Recurrence of Spontaneous Pneumothorax.

BACKGROUND: Video-assisted thoracoscopic surgery is the standard procedure for treatment of spontaneous pneumothorax. However, postoperative recurrence is relatively common even if an absorbable covering sheet is used for reinforcement of the visceral pleura. Injection of a high concentration glucose solution to the thoracic cavity was recently reported to be effective in stopping postoperative air leakage or as a prophylactic procedure to prevent postoperative recurrence of spontaneous pneumothorax. Therefore, we used 50 mL of a 50% glucose solution for pleural coating (GPC) on an absorbable sheet intraoperatively to prevent postoperative recurrence of spontaneous pneumothorax. This is a retrospective study, and patient backgrounds are heterogeneous. We evaluated the feasibility of GPC using propensity scores to adjust for heterogeneity in their backgrounds. METHODS: Between January 2010 and December 2017, 376 patients who underwent video-assisted thoracoscopic surgery, with or without GPC, were evaluated. The GPC group consisted of 106 patients, and the non-GPC group consisted of 270. We analyzed the factors preventing postoperative recurrence of spontaneous pneumothorax by univariate analysis and Cox regression analysis with or without propensity score matching. RESULTS: Univariate analysis revealed age of 25 or older, smoking habit, no history of an ipsilateral operation, and GPC were significant factors preventing postoperative recurrence. GPC significantly prevented postoperative recurrence as shown by Cox regression analysis with propensity score matching (hazard ratio, 0.15; p = 0.014) and the inverse-probability of treatment weighted method (hazard ratio, 0.23; p = 0.0038). CONCLUSIONS: Intraoperative GPC significantly reduced the postoperative recurrence rate of spontaneous pneumothorax.

[Injection of High Concentration Glucose Solution for Pleural Coating Reduces Postoperative Recurrence of Spontaneous Pneumothorax;A Short-term Retrospective Study].

BACKGROUND: Video-assisted thoracoscopic surgery (VATS) is the standard treatment for patients with spontaneous pneumothorax (SP). However, postoperative recurrence is not infrequent even with an absorbable covering sheet used to reinforce the visceral pleura. Recent reports suggest that intraoperative injection of a highly concentrated glucose solution into the thoracic cavity provides effective prophylaxis against postoperative SP recurrence. Since September 2015, we have been injecting 50 ml of 50 % glucose solution intraoperatively for pleural coating (GPC) around an absorbable sheet to prevent postoperative SP recurrence. METHODS: We evaluated 340 patients who underwent VATS between February 2011 and June 2017(88 patients:GPC group, 252:non-GPC group), and we retrospectively analyzed the efficacy of GPC in preventing postoperative SP recurrence. RESULTS: One year postoperative recurrence rates of GPC and non-GPC groups were 9.0 and 17.9%,respectively. The log-rank test revealed GPC as a significant factor in preventing postoperative recurrence (p=0.020). No severe adverse events occurred in either group. Minor postoperative complications, viz., high blood sugar, high volume of chest tube drainage occurred in the GPC group. CONCLUSION: Application of GPC is beneficial in reducing postoperative recurrence of SP.

Feasibility of single-incision thoracoscopic surgery using a modified chest wall pulley for primary spontaneous pneumothorax: a propensity score matching analysis.

PURPOSE: Recently, single-incision thoracoscopic surgery (SITS) has been recognized as a favorable treatment choice for primary spontaneous pneumothorax (PSP) compared with conventional three-port video-assisted thoracoscopic surgery (VATS). However, conventional SITS bullectomy often results in collisions with surgical devices. Therefore, we devised a method of SITS using a chest wall pulley for lung excision (PulLE) and modified PulLE (mPulLE) system, which substitutes threads to eliminate such collisions. We compared the mPulLE system with conventional procedures using propensity score matching (PSM) to adjust for patient backgrounds. METHODS: Using PSM, we evaluated the surgical results of 210 PSP patients who underwent VATS, including mPulLE (n = 23) and three-port VATS (n = 102), at our institution between January 2010 and August 2016. RESULTS: We selected 17 mPulLE cases and 17 three-port VATS. There were no marked differences between the groups in the patient backgrounds or surgical results. However, there was a significant difference between the mPulLE cases and the three-port VATS cases in the operative time (71.7 ± 15.7 vs. 85.9 ± 25.5 min, respectively, P = 0.0388) and the number of autosutures used (3.6 ± 1.2 vs. 4.5 ± 1.2, respectively, P = 0.0178). CONCLUSION: The surgical results of mPulLE in patients with PSP with multiple lesions were equivalent to those achieved with three-port VATS under the same conditions.

Modified Chest Wall Pulley for Lung Excision during Single-Incision Thoracoscopic Surgery for Primary Spontaneous Pneumothorax.

We reported the feasibility of single-incision thoracoscopic surgery bullectomy using a chest wall pulley for lung excision (PulLE) in patients with primary spontaneous pneumothorax (PSP). PulLE has many merits including comfort of manipulation, cosmetic advantages, etc., compared to other procedures. However, our method was utilized for relatively straightforward cases. The PulLE was contraindicated for PSPs with multiple or comprehensive bullae. Therefore, we developed the modified PulLE (mPulLE) to treat such cases in February 2015. Although one chest wall pulley is placed in the thoracic cavity for a PulLE, two are used for an mPulLE. Herein, we describe the mPulLE technique.

[Propensity-score-matched Comparison of Postoperative Pain Between Young and Elderly Patients Who Underwent Video-assisted Thoracoscopic Surgery for Spontaneous Pneumothorax].

Video-assisted thoracoscopic surgery (VATS) is the standard treatment for spontaneous pneumothorax(SP). Although VATS has decreased the postoperative pain in comparison with conventional thoracotomy, the procedure still often requires sufficient postoperative pain management especially for young patients, and the present study on the postoperative pain management focused on the age difference was designed. Using the numerical rating scale, we compared postoperative pain between the young group(36 patients) and the elderly group (36 patients) selected by propensity score matching in order to adjust for the patients' backgrounds. Although the young group had significantly stronger pain than the elderly group immediately after surgery(4.9±2.5 vs.3.2±2.4, p=0.002), it improved promptly. Moreover, the young group required significantly more frequent continuous infusions of opioids after surgery( p=0.001). In conclusion, it is considered that the postoperative pain management in the pneumothorax surgery should be customized according to the age.

Association between postoperative bulla neogenesis at the staple line and resected lung weight for primary spontaneous pneumothorax: a retrospective study using the inverse-probability of treatment weighted method in patients grouped according to age.

BACKGROUND: Bullectomy using autosutures is the standard procedure in patients with primary spontaneous pneumothorax (PSP). However, postoperative bulla neogenesis (POBN) along the staple line is relatively common and promotes PSP recurrence. We have previously reported the relationship between POBN and resected lung weight (LW). However, recently published data indicate that young patients with PSP have a high postoperative recurrence rate. Therefore, we evaluated the relationship between POBN and LW in PSP patients, subdivided according to age. METHODS: Between February 2011 and April 2016, 96 lung-resection sites in 67 patients who underwent bullectomy were evaluated. Patients were subdivided into two groups by age: Y group (<25 years, 56 sites) and O group (≥25 years, 40 sites). We used the inverse-probability of treatment weighted (IPTW) method to adjust for the heterogeneity in their backgrounds. POBN was diagnosed by computed tomography. RESULTS: Cox regression analysis for the O group indicated that LW ≥3.0 g was a significant risk factor for POBN (P=0.049). For the Y group, no association between lung weight and POBN was observed. CONCLUSIONS: A LW ≥3.0 g is a significant risk factor for POBN in individuals aged ≥25 years.

Novel paravertebral block during single-incision thoracoscopic surgery for primary spontaneous pneumothorax.

Recently, the use of paravertebral block (PVB) during thoracic surgery has been re-evaluated, as it is not inferior to epidural anaesthesia for postoperative pain control, and has been associated with fewer complications (e.g., hematoma of epidural, hypotension, urinary retention, postoperative nausea and vomiting). No reports have described intraoperative catheterization for PVB during single-incision thoracoscopic surgery (SITS) as distinct from thoracotomy or multi-ports video-assisted thoracoscopic surgery. We describe a case of SITS bullectomy using a chest wall pulley for lung excision to treat primary spontaneous pneumothorax and 25 catheterizations for PVB during SITS that have been performed since June 2013. Our novel technique is both easy and safe. It is ideal to combine PVB with SITS because both methods are less invasive.