Autologous blood patch intraparenchymal injection reduces the incidence of pneumothorax and the need for chest tube placement following CT-guided lung biopsy: a systematic review and meta-analysis.

PURPOSE: To assess the effectiveness of autologous blood patch intraparenchymal injection during CT-guided lung biopsies with a focus on the incidence of pneumothorax and the subsequent requirement for chest tube placement. METHODS: A comprehensive search of major databases was conducted to identify studies that utilized autologous blood patches to mitigate the risk of pneumothorax following lung biopsies. Efficacy was next assessed through a meta-analysis using a random-effects model. RESULTS: Of the 122 carefully analyzed studies, nine, representing a patient population of 4116, were incorporated into the final analysis. Conclusion deduced showed a noteworthy reduction in the overall incidence of pneumothorax (RR = 0.65; 95% CI 0.53-0.80; P = 0.00) and a significantly decline in the occasion for chest tube placement due to pneumothorax (RR = 0.45; 95% CI 0.32-0.64; P = 0.00). CONCLUSIONS: Utilizing autologous blood patch intraparenchymal injection during the coaxial needle retraction process post-lung biopsy is highly effective in diminishing both the incidence of pneumothorax and consequent chest tube placement requirement.

[Predictive model for additional intraoperative placement of chest drainage after thoracoscopic lobectomy]. / Prognosticheskaya model' dlya dopolnitel'noi intraoperatsionnoi ustanovki plevral'nogo drenazha pri torakoskopicheskoi lobektomii.

OBJECTIVE: To create a prognostic model determining the risk of tension pneumothorax and the need for intraoperative installation of additional drainage after thoracoscopic lobectomy. MATERIAL AND METHODS: A retrospective multiple-center study included patients who underwent thoracoscopic lobectomy for lung cancer between 2016 and 2022. One drainage tube was used after surgery in all cases. We synthesized data to expand patient selection using the Riley method and machine learning algorithm. In total, treatment outcomes in 1458 patients were analyzed. After identifying significant factors, we performed binary logistic regression analysis using backward stepwise inclusion of variables in accordance with the Akaike information criterion. After validating the model using the Bootstrap method (400 iterations) and original data set, we created a nomogram determining scoring characteristics, linear predictors and risk of postoperative tension pneumothorax. RESULTS: The incidence of tension pneumothorax was 4.53% (n=66). The most significant variables associated with pneumothorax and the need for additional pleural drainage were adhesions, intraoperative lung suturing, unclear interlobar groove, enlarged intrapulmonary lymph nodes and chronic obstructive pulmonary disease (p<0.001). The model's C-index was 0.957, mean absolute calibration error - 0.6%, calibration curve slope - 0.959. A score of 26 indicated a 95% risk of postoperative pneumothorax. CONCLUSION: We developed a prognostic model for tension pneumothorax after thoracoscopic lobectomy. Nomogram makes it possible to make a decision on intraoperative installation of additional pleural drainage tube and prevent complications associated with postoperative lung collapse.

Surfactant therapy guided by tests for lung maturity in preterm infants at risk of respiratory distress syndrome.

BACKGROUND: Administration of various exogenous surfactant preparations has been shown to decrease lung injury and pneumothorax and improve survival in very preterm infants with respiratory distress syndrome (RDS). There is no consensus on the threshold for surfactant administration, to allow timely intervention and avoid over-treatment, also considering the invasiveness of the procedure and its cost. Rapid tests for lung maturity, which include the click test, lamellar body counts and stable microbubble test, might guide the identification of those infants needing surfactant administration. OBJECTIVES: To assess the effects of surfactant treatment guided by rapid tests for surfactant deficiency in preterm infants at risk for or having RDS. Comparison 1: In preterm infants at risk for RDS, does surfactant treatment guided by rapid tests for surfactant deficiency compared to prophylactic surfactant administration to all high-risk infants minimize the need for surfactant treatment and prevent bronchopulmonary dysplasia and mortality? Comparison 2: In preterm infants who require early respiratory support, does surfactant treatment guided by rapid tests for surfactant deficiency compared to surfactant therapy provided to infants with RDS diagnosed on clinical and radiologic criteria minimize the need for surfactant treatment and prevent bronchopulmonary dysplasia and mortality? SEARCH METHODS: We searched in October 2022 CENTRAL, PubMed, Embase and three additional trial registries. We also screened the reference lists of included studies and related systematic reviews for studies not identified by the database searches. SELECTION CRITERIA: We included randomized controlled trials (RCTs) and quasi-RCTs evaluating rapid tests after birth for surfactant deficiency in infants at high risk of RDS or requiring respiratory support. We specified two comparisons: 1)surfactant treatment guided by rapid tests for surfactant deficiency versus prophylactic surfactant administration to all high-risk infants in extremely preterm (less than 28 weeks' gestation) and very preterm (28 to 32 weeks' gestation); 2)surfactant treatment guided by rapid tests for surfactant deficiency versus surfactant therapy provided to preterm infants (less than 37 weeks' gestation) with RDS diagnosed on clinical and radiologic criteria. DATA COLLECTION AND ANALYSIS: We used standard Cochrane methods. We used the fixed-effect model with risk ratio (RR) and risk difference (RD), with their 95% confidence intervals (CIs) for dichotomous data. Our primary outcomes were: neonatal mortality, mortality prior to hospital discharge, bronchopulmonary dysplasia and the composite outcome bronchopulmonary dysplasia or mortality. We used GRADE to assess the certainty of evidence. MAIN RESULTS: We included three RCTs enrolling 562 newborn infants in this review. No studies compared surfactant treatment guided by rapid tests for surfactant deficiency versus prophylactic surfactant administration to all high-risk infants. Comparing surfactant therapy guided by rapid tests for surfactant deficiency versus surfactant therapy provided to infants with RDS diagnosed on clinical and radiologic criteria. No studies reported neonatal mortality. Compared with surfactant therapy provided to infants with RDS diagnosed on clinical and radiologic criteria, the evidence is very uncertain about the effect of surfactant treatment guided by rapid tests for surfactant deficiency on mortality prior to hospital discharge: RR 1.25, 95% CI 0.65 to 2.41, RD 0.01, 95% CI -0.03 to 0.05, 562 participants, 3 studies; I² for RR and RD = 75% and 43%, respectively; very low-certainty evidence. Surfactant treatment guided by rapid tests for surfactant deficiency may result in little to no difference in bronchopulmonary dysplasia: RR 0.90, 95% CI 0.61 to 1.32, RD -0.02, 95% CI -0.08 to 0.04, 562 participants, 3 studies; I² for RR and RD = 0%; low-certainty evidence. No studies reported the composite outcome bronchopulmonary dysplasia or mortality. Surfactant treatment guided by rapid tests for surfactant deficiency may result in little to no difference in surfactant utilization (RR 0.97, 95% CI 0.85 to 1.11, RD -0.02, 95% CI -0.10 to 0.06, 562 participants, 3 studies, I² for RR and RD = 63% and 65%, respectively, low-certainty evidence), and any pneumothorax (RR 0.53, 95% CI 0.15 to 1.92, RD -0.01, 95% CI -0.04 to 0.01, 506 participants, 2 studies, I² for RR and RD = 0%, low-certainty evidence) compared with surfactant therapy provided to infants with RDS diagnosed on clinical and radiologic criteria. No studies reported moderate to severe neurodevelopmental impairment. We identified two large ongoing RCTs. AUTHORS' CONCLUSIONS: No studies compared surfactant treatment guided by rapid tests for surfactant deficiency to prophylactic surfactant administration to all high-risk infants. Low to very low-certainty evidence from three studies is available on surfactant therapy guided by rapid tests for surfactant deficiency versus surfactant therapy provided to infants with RDS diagnosed on clinical and radiologic criteria. No studies reported neonatal mortality, the composite outcome 'bronchopulmonary dysplasia or mortality', or neurodevelopmental outcomes. Compared with surfactant therapy provided to infants with RDS diagnosed on clinical and radiologic criteria, the evidence is very uncertain about the effect of surfactant treatment guided by rapid tests for surfactant deficiency on mortality prior to hospital discharge. Surfactant treatment guided by rapid tests for surfactant deficiency may result in little to no difference in bronchopulmonary dysplasia, surfactant utilization and any pneumothorax. The findings of the two large ongoing trials identified in this review are likely to have an important impact on establishing the effects of surfactant treatment guided by rapid tests for surfactant deficiency in preterm infants.

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.

Early nasal intermittent positive pressure ventilation (NIPPV) versus early nasal continuous positive airway pressure (NCPAP) for preterm infants.

BACKGROUND: Nasal continuous positive airway pressure (NCPAP) is a strategy to maintain positive airway pressure throughout the respiratory cycle through the application of a bias flow of respiratory gas to an apparatus attached to the nose. Early treatment with NCPAP is associated with decreased risk of mechanical ventilation exposure and might reduce chronic lung disease. Nasal intermittent positive pressure ventilation (NIPPV) is a form of noninvasive ventilation delivered through the same nasal interface during which patients are exposed to short inflations, along with background end-expiratory pressure. OBJECTIVES: To examine the risks and benefits of early (within the first six hours after birth) NIPPV versus early NCPAP for preterm infants at risk of or with respiratory distress syndrome (RDS). Primary endpoints are respiratory failure and the need for intubated ventilatory support during the first week of life. Secondary endpoints include the incidence of mortality, chronic lung disease (CLD) (oxygen therapy at 36 weeks' postmenstrual age), pneumothorax, duration of respiratory support, duration of oxygen therapy, and intraventricular hemorrhage (IVH). SEARCH METHODS: Searches were conducted in January 2023 in CENTRAL, MEDLINE, Embase, Web of Science, and Dissertation Abstracts. The reference lists of related systematic reviews and of studies selected for inclusion were also searched. SELECTION CRITERIA: We considered all randomized and quasi-randomized controlled trials. Eligible studies compared NIPPV versus NCPAP treatment, starting within six hours after birth in preterm infants (< 37 weeks' gestational age (GA)). DATA COLLECTION AND ANALYSIS: We collected and analyzed data using the recommendations of the Cochrane Neonatal Review Group. MAIN RESULTS: We included 17 trials, enrolling 1958 infants in this review. NIPPV likely reduces the rate of respiratory failure (risk ratio (RR) 0.65, 95% confidence interval (CI) 0.54 to 0.78; risk difference (RD) -0.08, 95% CI -0.12 to -0.05; 17 RCTs, 1958 infants; moderate-certainty evidence) and needing endotracheal tube ventilation (RR 0.67, 95% CI 0.56 to 0.81; RD -0.07, 95% CI -0.11 to -0.04; 16 RCTs; 1848 infants; moderate-certainty evidence) amongst infants treated with early NIPPV compared with early NCPAP. The meta-analysis demonstrated that NIPPV may reduce the risk of developing CLD compared to CPAP (RR 0.70, 95% CI 0.52 to 0.92; 12 RCTs, 1284 infants; low-certainty evidence) slightly. NIPPV may result in little to no difference in mortality (RR 0.82, 95% CI 0.62 to 1.10; 17 RCTs; 1958 infants; I2 of 0%; low-certainty evidence), the incidence of pneumothorax (RR 0.92, 95% CI 0.60 to 1.41; 16 RCTs; 1674 infants; I2 of 0%; low-certainty evidence), and rates of severe IVH (RR 0.98, 95% CI 0.53 to 1.79; 8 RCTs; 977 infants; I2 of 0%; low-certainty evidence). AUTHORS' CONCLUSIONS: When applied within six hours after birth, NIPPV likely reduces the risk of respiratory failure and the need for intubation and endotracheal tube ventilation in very preterm infants (GA 28 weeks and above) with respiratory distress syndrome or at risk for RDS. It may also decrease the rate of CLD slightly. However, most trials enrolled infants with a gestational age of approximately 28 to 32 weeks with an overall mean gestational age of around 30 weeks. As such, the results of this review may not apply to extremely preterm infants that are most at risk of needing mechanical ventilation or developing CLD. Additional studies are needed to confirm these results and to assess the safety of NIPPV compared with NCPAP alone in a larger patient population.

Evaluating and developing sealants for the prevention of pulmonary air leakage: A systematic review of animal models.

Sealants may provide a solution for pulmonary air leakage (PAL), but their clinical application is debatable. For sealant comparison, standardized animal models are lacking. This systematic review aims to assess methodology and quality of animal models for PAL and sealant evaluation. All animal models investigating lung sealing devices (e.g., staplers, glues, energy devices) to prevent or treat PAL were retrieved systematically from Embase, Pubmed and Web of science. Methodological study characteristics, risk of bias, reporting quality and publication bias were assessed. A total of 71 studies were included (N = 75 experiments, N = 1659 animals). Six different species and 18 strains were described; 92% of experiments used healthy animals, disease models were used in only six studies. Lesions to produce PAL were heterogenous, and only 11 studies used a previously reported technique, encompassing N = 5 unique lesions. Clinically relevant outcomes were used in the minority of studies (imaging 16%, air leak 10.7%, air leak duration 4%). Reporting quality was poor, but revealed an upward trend per decade. Overall, high risk of bias was present, and only 18.7% used a negative control group. All but one study without control groups claimed positive outcomes (95.8%), in contrast to 84.3% using positive or negative control groups, which also concluded equivocal, adverse or inconclusive outcomes. In conclusion, animal studies evaluating sealants for prevention of PAL are heterogenous and of poor reporting quality. Using negative control groups, disease models and quantifiable outcomes seem important to increase validity and relevance. Further research is needed to reach consensus for model development and standardization.

Lung deflation while placing a subclavian vein catheter: Our experience in minimizing the risk of pneumothorax.

PURPOSE: Lung deflation may reduce the risk of pneumothorax based on the assumption that the distance between the subclavian vein and the lung pleura would increase as well as the diameter of the vein. We aim to provide evidence to support the suggested desideratum of deflation in adults. METHODS: A prospective database was created that included patients who underwent subclavian vein catheterization for monitoring and therapeutic reasons from January 2014 to January 2020. Measurements using ultrasonography of the diameter of the subclavian vein were taken while the patient's breathing was controlled by a ventilator and then repeated after disconnecting the mechanical ventilation and opening the pressure relief valve. RESULTS: A total of 123 patients were enrolled, with an average age of 41.9 years. The subclavian vein diameter was measured during controlled breathing with a mean average of 8.1 ± 0.6mm in males and 7.1 ± 0.5mm in females. The average increase after lung deflation with the pressure relief valve closed was 8.0± 5.1mm in males and 13.9 ± 5.4mm in females. An increase was noticed after opening a pressure valve, and the means were 5.5 ± 2.8mm in males and 5.1 ± 3.3mm in females. The catheter malposition rate was 0.8. CONCLUSION: The benefit of interrupting mechanical ventilation and lung deflation lies within possibly avoiding pneumothorax as a complication of subclavian vein catheterization. These findings support the need for evidence regarding the curtailment of pneumothorax incidence in spontaneously breathing patients and the suggested increase in first-time punctures and success rates.

Combined autologous blood patch-immediate patient rollover does not reduce the pneumothorax or chest drain rate following CT-guided lung biopsy compared to immediate patient rollover alone.

PUPROSE: The purpose of this study was to evaluate a combined autologous blood-patch (ABP)-immediate patient rollover (IPR) technique compared with the IPR technique alone on the incidence of pneumothorax and chest drainage following CT-guided lung biopsy. METHODS: In this interventional cohort study of both prospectively and retrospectively acquired data, 652 patients underwent CT-guided lung biopsy. Patient demographics, lesion characteristics and technical biopsy variables including the combined ABP-IPR versus IPR alone were evaluated as predictors of pneumothorax and chest drain rates using regression analysis. RESULTS: The combined ABP-IPR technique was performed in 259 (39.7 %) patients whilst 393 (60.3 %) underwent IPR alone. There was no significant difference in pneumothorax rate or chest drains required between the combined ABP-IPR vs IPR groups (p =.08, p =.60 respectively). Predictors of pneumothorax adjusted for the combined ABP-IPR and IPR alone groups included age (p =.02), lesion size (p =.01), location (p =.005), patient position (p =.008), emphysema along the needle track (p =.005) and lesion distance from the pleura (p =.02). Adjusted predictors of chest drain insertion included lesion location (p =.09), patient position (p =.002), bullae crossed (p =.02) and lesion distance from the pleura (p =.02). CONCLUSION: The combined ABP-IPR technique does not reduce the pneumothorax or chest drain rate compared to the IPR technique alone. Utilising IPR without an ABP following CT-guided lung biopsy results in similar pneumothorax and chest drain rates while minimising the potential risk of systemic air embolism.

The effect of polyglycolic acid sheet in preventing postoperative recurrent pneumothorax: a prospective cohort study.

BACKGROUND: Primary spontaneous pneumothorax occasionally relapses, even after bullectomy; therefore, coverage of the bullectomy staple line for pleural reinforcement is common in Japan. However, the appropriate covering materials have not yet been determined. METHODS: This was a longitudinal prospective cohort study. Data were available for patients aged < 40 years with primary spontaneous pneumothorax who underwent their first thoracoscopic bullectomy between July 2015 and June 2021. We used oxidized regenerated cellulose (ORC) sheets from July 2015 to June 2018, and polyglycolic acid (PGA) sheets from July 2018 to June 2021. The postoperative recurrence-free survival rate was evaluated. The characteristics of the recurrent cases (radiographic, intraoperative, and pathological findings) were also evaluated. The extent of pleural adhesions was classified into the following three groups: none, medium, or extensive. RESULTS: A total of 187 patients were included in the study. There were 92 and 95 participants in the ORC and PGA sheet groups, respectively. The postoperative recurrence-free survival rates were significantly higher in the PGA sheet group than in the ORC sheet group (ORC group vs. PGA group, 82.9% vs. 95.4%, p = 0.031). In recurrent cases, there was a significant difference in terms of pleural adhesion (0.0% [12 of 12, none] vs. 100.0% [four of four, extensive], p < 0.001). CONCLUSIONS: Compared with ORC sheets, PGA sheets are an effective material for preventing early recurrence of primary spontaneous pneumothorax. Strong local pleural adhesions potentially contribute to decreasing recurrence.

Biopsy-tract haemocoagulase injection reduces major complications after CT-guided percutaneous transthoracic lung biopsy.

AIM: To determine whether the injection of haemocoagulase into the biopsy tract can reduce pneumothorax and pulmonary haemorrhage after computed tomography (CT)-guided percutaneous transthoracic lung biopsy (PTLB). MATERIALS AND METHODS: A retrospective study was performed involving patients with undiagnosed pulmonary lesions scheduled for PTLB between January 2020 and March 2021. Patients were assigned to the haemocoagulase group or the non-haemocoagulase group. After CT-guided biopsies were performed with a 17 G coaxial system, patients in the haemocoagulase group received a haemocoagulase injection (0.2-0.5 units) in the biopsy tract as the sheath was withdrawn. Postoperative image studies were performed to evaluate complications, including pneumothorax and pulmonary haemorrhage. Factors, including the patient's position, lesion location, and pathological results, were evaluated to determine their associations with the complications. RESULTS: A total of 100 patients were included, with 44 men and a mean age of 53 years old. The overall incidences of pneumothorax and pulmonary haemorrhage were 15% and 13%, respectively. The incidences of pneumothorax and pulmonary haemorrhage were statistically significantly lower in the haemocoagulase group (8% and 6%, respectively) than in the non-haemocoagulase group (22% and 20%, respectively; p=0.04 and 0.03, respectively). There was no statistically significant difference in haemoptysis between the haemocoagulase (6%) and non-haemocoagulase (2%) groups (p=0.23). There were also no statistically significant associations of pneumothorax or pulmonary haemorrhage with the patients' positions, lesion location, or pathological results. CONCLUSION: Biopsy tract haemocoagulase injection reduced the incidences of postoperative pneumothorax and pulmonary haemorrhage after PTLB.

Sirolimus reduces the risk of pneumothorax recurrence in patients with lymphangioleiomyomatosis: a historical prospective self-controlled study.

BACKGROUND: Spontaneous pneumothorax has a high incidence and high rate of recurrence in patients with lymphangioleiomyomatosis (LAM). The risk factors for pneumothorax and the effects of sirolimus on pneumothorax in patients with LAM are unknown. In our study, multivariate logistic regression was applied to a cross-sectional cohort to investigate factors associated with pneumothorax in LAM patients. Kaplan-Meier analysis was applied in the historical prospective self-controlled study to determine whether sirolimus reduces the risk of pneumothorax recurrence in patients with LAM. RESULTS: Of the 399 patients registered with LAM-CHINA at our center between May 10, 2017 and August 31, 2020, 142 had a history of pneumothorax at registration. High CT grade and age at presentation ≤ 35 years were associated with a higher risk of pneumothorax in patients with LAM. Postmenopausal status was correlated with a lower risk of pneumothorax. In the historical prospective self-controlled study, the 5-year probability of pneumothorax recurrence was 80% lower in the sirolimus group than in the control group (hazard ratio for pneumothorax recurrence, 0.20; 95% CI, 0.14 to 0.30, P < 0.001 by log-rank test). CONCLUSION: Sirolimus reduced the risk of pneumothorax recurrence in LAM patients.

Preventive tract embolization with gelatin sponge slurry is safe and considerably reduces pneumothorax after CT-guided lung biopsy with use of large 16-18 coaxial needles.

OBJECTIVE: To evaluate the clinical impact of the tract embolization technique using gelatin sponge slurry after percutaneous CT-guided lung biopsy. METHODS: We retrospectively compared coaxial needle CT-guided lung biopsies performed without embolization (100 patients) and with the tract embolization technique using a mixture of iodine and gelatin sponge slurry (105 patients) between June 2012 and July 2020. Uni- and multivariate analyses were performed between groups to determine risk factors of pneumothorax. RESULTS: Patients with gelatin sponge slurry tract embolization had statistically lower rates of pneumothorax ((17.1% vs 39%, p < 0.001). In univariate analysis, tract embolization (OR = 0.32, CI = 0.17-0.61 p<0.001) and nodule size >2 cm (OR = 0.33 CI = 0.14-0.8 p = 0.013) had a protective effect on pneumothorax. The puncture path lengths > 2-20 mm and >20 mm were risk factors for pneumothorax (OR = 3.35 IC = 1.44-8.21 p = 0.006 and OR = 4.36 CI = 1.98-10.29 p<0.001, respectively). In multivariate regression analysis, tract embolization had a protective effect of pneumothorax (OR = 0.25, CI = 0.12-0.51, p < 0.001). The puncture path lengths > 2-20 mm and >20 mm were risk factors for pneumothorax (p = 0.030 and p = 0.002, respectively). CONCLUSIONS: The tract embolization technique using iodinated gelatin sponge slurry is safe and considerably reduces pneumothorax after percutaneous CT-guided lung biopsy. Our results suggest that it could be use in clinical routine. ADVANCES IN KNOWLEDGE: The systemic use of gelatin sponge slurry is safe and reduces considerably the rate of pneumothorax upon needle removal when CT-guided core biopsies are performed using large 16-18G coaxial needles.

Artificial pneumothorax suppresses postoperative inflammatory reaction in mediastinal tumor surgery.

OBJECTIVE: The induction of artificial pneumothorax has many intraoperative advantages. However, few reports on the postoperative effects of artificial pneumothorax induction are available. In this study, we investigated the effect of artificial pneumothorax on postoperative clinical course in patients with mediastinal tumors. METHODS: We retrospectively investigated the clinical courses of 89 patients who had undergone mediastinal tumor resection between January 2010 and December 2020. Sixty-five patients had undergone resection with artificial pneumothorax. RESULTS: The tumor location significantly varied across patients. The proportion of patients in whom artificial pneumothorax was induced was higher among those having anterior mediastinal tumors. The number of ports and the total skin incision length were significantly higher in patients without artificial pneumothorax. The C-reactive protein level elevation on postoperative day 2 and pleural effusion at 24 h after surgery were significantly higher in patients without artificial pneumothorax. Furthermore, the albumin level reduction and hospital stay after surgery were significantly lower in patients with artificial pneumothorax. Multiple regression analysis showed that the use of artificial pneumothorax was an independent predictive factor of the C-reactive protein level elevation on postoperative day 2 and pleural effusion at 24 h after surgery. In patients without artificial pneumothorax, the operation time positively correlated with the C-reactive protein level (r = 0.646, P < 0.001). CONCLUSIONS: Artificial pneumothorax suppressed the postoperative inflammatory response, pleural effusion, and albumin reduction, and shortened the hospital stay in patients undergoing mediastinal tumor surgery.

Toward a Next-Generation Digital Chest Tube.

Chest tubes in patients who have undergone pulmonary resection with pleural air leak are painful, impair ventilatory mechanics, and increase hospital length of stay and costs. Despite these well-documented concerns, current protocols for chest tube management in this setting are not well supported by evidence. Excessive suction applied to chest tubes has been associated with prolonged air leak due to alveolar over-distension, and most practitioners intuit that suction should be minimized to the lowest level needed to maintain desired pleural apposition. Unfortunately, there is no evidence-based protocol for the establishment of minimal adequate suction. Digital suction devices in current clinical use can identify air leak resolution preventing the delay of chest tube removal but cannot guide suction minimization while an air leak persists. We recently described a monitor of lung expansion in a porcine model of pleural air leak that could detect loss of pleural apposition continuously in real-time based on electrical impedance readings obtained directly from the surface of the lung via chest tube-embedded electrodes. The value of the impedance signal was "in-range" when pleural apposition was present but became abruptly "out-of-range" when pneumothorax due to inadequate suction developed. These findings suggested that a digitally controlled suction pump system could be programmed to recognize the development of pneumothorax and automatically identify and set the minimum level of suction required to maintain pleural apposition. We present here preliminary proof of concept for this system.

Multicentre, prospective, observational study investigating the most appropriate surgical option that can prevent the recurrence of primary spontaneous pneumothorax after surgery: the PATCH study, protocol.

INTRODUCTION: Thoracoscopic surgery is performed for refractory or recurrent primary spontaneous pneumothorax (PSP). To reduce postoperative recurrence, additional treatment is occasionally adopted during surgery after bulla resection. However, the most effective method has not been fully elucidated. Furthermore, the preference for additional treatment varies among countries, and its efficacy in preventing recurrence must be evaluated based on settings tailored for the conditions of a specific country. The number of registries collecting detailed data about PSP surgery is limited. Therefore, to address this issue, a prospective multicentre observational study was performed. METHODS AND ANALYSIS: This multicentre, prospective, observational study will enrol 450 participants aged between 16 and 40 years who initially underwent PSP surgery. Data about demographic characteristics, disease and family history, surgical details, and CT scan findings will be collected. Follow-up must be conducted until 3 years after surgery or in the event of recurrence, whichever came first. Patients without recurrence will undergo annual follow-up until 3 years after surgery. The primary outcome is the rate of recurrence within 2 years after surgery. A multivariate analysis will be performed to compare the efficacy of different surgical options. Then, adverse outcomes correlated with various treatments and the feasibility of treatment methods will be compared. ETHICS AND DISSEMINATION: This study was approved by the local ethics committee of all participating centres. The findings will be available in 2025, and they can be used as a basis for clinical decision-making regarding appropriate options for the initial PSP surgery. TRIAL REGISTRATION NUMBER: NCT04758143.

Efficacy of Commercial Chest Seal Adherence and Tension Pneumothorax Prevention: A Systematic Review of Quantitative Studies.

BACKGROUND: Penetrating thoracic injuries account for an essential subset of battlefield and civilian injuries that result in death. Current recommendations are to use commercially available nonocclusive chest seals. We review current evidence for which chest seal(s) is likely to be the most effective in treating open pneumothoraces. METHODS: A systematic review was conducted in accordance with the PRIMSA 2009 standard systematic review methodology, except where noted. The databases Pubmed, MEDLINE, CINAHL, Scopus, and gray sources were searched for all English-language, full-manuscript, experimental, quantitative studies of humans and animals concerning seal adherence or their efficacy at preventing tension pneumothoraces published between 1990 and 2020. A numerical analysis was used to provide the consensus recommendation. RESULTS: Of 683 eligible identified articles [PubMed 528 (77.3%), Scopus 87 (12.7%), CINAHL 67 (9.8%), one (0.1%) unpublished], six (0.9%) articles were included. Synthesis of all studies' results suggests a consensus recommendation for the Hyfin Vent Chest Seal and Russell Chest Seal. These two were the most effective chest seals, as previously investigated in a quantifiable, experimental study. CONCLUSION: While chest seals are recommended in civilian and military prehospital medicine to improve patient survival, current evidence concerning the individual device's efficacy is limited. Further scientific, quantitative research is needed to clarify which commercially available chest seals are most effective and provide patients with penetrating chest trauma the best possible method for preventing or mitigating tension pneumothoraces.

Two-Stage Bronchoscopic Endobronchial Valve Treatment Can Lead to Progressive Lung Volume Reduction and May Decrease Pneumothorax Risk.

Background: Since successful development of endobronchial valves (EBV) as treatment for severe emphysema, its main complication, pneumothorax, remains an important concern. Objective: We hypothesized that a two-step EBV implantation, during two distinct iterative procedures could lead to a more progressive target lobe volume reduction (TLVR) and thus ipsilateral lobe re-expansion, resulting in a significant decrease in the pneumothorax rate. Methods: This retrospective bi-center study carried out by Limoges and Toulouse University Hospitals included patients following the inclusion criteria established by the BLVR expert panel. All patients were treated by two distinct procedures: first, EBVs were placed in all but the most proximal segment or sub-segment. The remaining segment was treated subsequently. All patients had a complete evaluation before treatment, and 3 months after the second procedure. Results: Out of 58 patients included, only 4 pneumothoraxes (7%) occurred during the study. The other complications were pneumonia and severe COPD exacerbation (8.6% and 13.7% of patients, respectively). Significant improvement was found for FEV1 (+19.6 ± 25%), RV (-468 ± 960mL), 6MWD (30 ± 85m), BODE Index (-1.4 ± 1.8 point) and TLVR (50.6 ± 35.1%). Significant TLVR (MCID) was obtained in 74.1% of patients (43/58). Conclusion: This new approach using EBV could reduce the incidence of pneumothorax without increasing other complication rates. Clinical and physiological outcomes are similar to those reported in studies using the conventional single-step treatment.

Gelfoam slurry tract occlusion after computed tomography-guided percutaneous lung biopsy: Does it prevent major pneumothorax?

INTRODUCTION: Computed tomography (CT)-guided lung biopsy is a frequently performed procedure in the diagnostic workup for suspicious lung nodules that can be complicated by pneumothorax. This retrospective study assessed the efficacy of biopsy tract occlusion with a gelatin sponge slurry for preventing post-biopsy pneumothorax. METHODS: Retrospective analysis was conducted on consecutive adult patients who underwent CT-guided lung biopsy over a 10-year period. Age, gender, existing chronic obstructive pulmonary disease (COPD), evidence of emphysema on CT, location of the lesion and the presence of pneumothorax on post-procedure CT and 4-h chest radiograph were recorded. RESULTS: Two hundred and ninety-six patients were included (126 patients in the non-gelfoam group and 170 in the gelfoam group). When gelfoam was used, risk of developing an immediate pneumothorax was lower (P = 0.032). Patients with emphysema were 2.4 times more likely to develop a delayed pneumothorax without gelfoam (P = 0.034). There was a significantly higher risk of both immediate and delayed pneumothorax in non-peripheral lesions without gelfoam (P = 0.001 and P = 0.002, respectively). The frequency of requiring a chest tube to treat a pneumothorax was 86% lower when gelfoam was used (P = 0.012). CONCLUSION: Gelfoam is effective in preventing immediate pneumothorax. In patients with emphysema, there was a significantly higher risk of delayed pneumothorax without gelfoam. Additionally, non-peripheral lesions were more likely to develop pneumothorax when gelfoam was not used. The use of gelfoam was especially important in preventing the development of major pneumothoraces that would require drainage with a chest tube.