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OBJECTIVE Spread through air spaces (STAS) is a pattern of invasion present in some adenocarcinomas (ADC). The goal of this study was to assess the impact of STAS in patients treated with different types of surgical resections and on the clinical outcome in patients with ADC of different diameters and with different degrees of nodal involvement. METHODS A total of 109 patients were reviewed. Complete surgical resection with systematic nodal dissection was achieved in all patients. The median follow-up was 65 months (3–90 months). RESULTS STAS was observed in 70 cases (64.2%); 13 patients (18.5%) had lymph node involvement (N1 and N2). Overall survival and progression-free survival were higher in patients without STAS (P = 0.042; P = 0.027). The presence of STAS in tumours ≤2 cm was a predictor of worse progression-free survival following sublobar resection compared to major resections (P = 0.011). Sublobar resection of N0 STAS-positive tumours was associated with worse long-term survival compared to a major resection (P = 0.04). Statistical analyses showed that age >70 years and recurrence were independent variables for survival; smoking pack-years >20, sublobar resection and nodal involvement were independent variables for recurrence; and smoking pack-years >20 were independent variables for a history of cancer and pleural invasion for local recurrence. CONCLUSIONS STAS seems to play a role in long-term survival, particularly for patients with N0 and tumours smaller than 2 cm. Further studies are necessary to validate this hypothesis.

Objectives: Chest tubes are routinely inserted after thoracic surgery procedures in different size and numbers. The aim of this study is to assess the efficacy of Smart Drain Coaxial drainage compared with two standard chest tubes in patients undergoing thoracotomy for pulmonary lobectomy.Methods: Ninety-eight patients (57 males and 41 females, mean age 68.3±7.4 years) with lung cancer undergoing open pulmonary lobectomy were randomized in two groups: 50 received one upper 28-Fr and one lower 32-Fr standard chest tube (ST group) and 48 received one 28-Fr Smart Drain Coaxial tube (SDC group). Hospitalization, quantity of fluid output, air leaks, radiograph findings, pain control and costs were assessed.Results: We performed 33 right upper lobectomies (17 ST, 16 SDC), 25 right lower (15 ST, 10 SDC), 20 left upper (8 ST, 12 SDC) and 19 left lower (10 ST, 9 SDC). SDC group showed shorter hospitalization (7.3 vs 6.1 days, p=0.02), lower pain in postoperative day-1 (p=0.02) and a lower use of analgesic drugs (p=0.04). Pleural effusion drainage was lower in SDC group in the first postoperative day (464±143 ml vs 408±141 ml, p=0.04) and regarding the average of the first three days (374±96 ml vs 324±95 ml, p=0.01). No difference in terms of fluid retention, residual pleural space, subcutaneous emphysema and complications after chest tubes removal was found. Conclusions: Smart Drain Coaxial chest tube seems a feasible option after thoracotomy for pulmonary lobectomy. The SDC group showed a shorter hospitalization and a decreased analgesic drugs use and, thus, a reduction of costs.

Background: Brain metastases (BMs) are the most common intracranial tumors in adults and the brain is one of the most frequent metastatic sites for non-small-cell lung cancer (NSCLC). Some studies have hypothesized that EGFR expression in the primary tumor may result in clinically radiological and prognostic changes in related brain metastases, comparable to EGFR's correlation with prognosis in primary brain tumors. There are no current studies that clinically and radiologically demonstrate a difference between BMs from EGFR-mutated and wild-type NSCLC.Methods: We performed a retrospective study to identify prognostic factors for the survival of patients with NSCLC-BMs by exploring the role of driving mutations in NSCLC, focusing on EGFR mutated status, and comparing all morphological, radiological, and clinical features of NSCLC-BMs with their outcome parameters in a cohort of surgically treated patients. Results: The final cohort consisted of 81 patients. The overall survival of the cohort was 15±17 months. The tumor-related edema was associated with neurological symptoms at the clinical onset of the disease (p=.048). We found that EGFR and ALK mutation status did not reach significant associations with age, sex, and the morphology of the lesions. EGFR mutation in the primary tumor is positively associated with higher edema and tumor volume (respectively 22.38±21.35cm3 versus 7.68±8.44cm3 and 72.44±60.71cm3 versus 31.92cm3 p=.046 and p=.028). Moreover, EGFR mutation is associated with a clinical debut of seizures (p=.004).Conclusions: The role of EGFR and ALK mutations of NSCLC on prognostic characteristics of BMs is still to be fully clarified; however the results retrieved from the present study suggest that the presence of EGFR mutations significantly correlates with bigger edema volume and higher incidence of seizures. In recent studies, while EGFR mutation status did not affect the immune pathway scores of primary lung tumors, the overall immune pathway scores in related BMs indicate a peculiar immunogenic phenotype that could explain a large amount of edema volume. This study could be considered the first clinical and radiological demonstration of this immunological phenotype.

In the present paper, the use of the topology optimization in a metal Additive Manufacturing application is discussed and applied to an automotive Body-in-White component called dash. The dash is in the front area of the Body-in-White, between the left-hand-side shock-tower and the Cross Car Beam, and its task is to support the steering column. The dash under investigation is an asymmetric rib-web aluminium casting part. The influence of Additive Manufacturing constraints together with modal and stiffness targets is investigated in view of mass reduction. The constraints drive the topology result towards a feasible and fully self-supporting Additive Manufacturing solution. A simplified finite element model of the steering column and of the Body-in-White front area is presented, and the limiting assumption of isotropic material for Additive Manufacturing is discussed. The optimization problem is solved with a gradient-based method relying on the Solid Isotropic Material with Penalization and on the RAtional Material with Penalization algorithms, considering the overhang angle constraint with given build directions. Three metals are tested: steel, aluminium and magnesium alloys. Topology optimization results with and without overhang angle constraints are discussed and compared. The aluminium solution, preferred for its lesser weight, has been preliminarily redesigned following the optimization results. The new dash concept has been validated by finite element considering stiffness, modal responses, and buckling resistance targets. The proposed dash design weighs 721 g compared to the 1537 g of the reference dash, with a weight reduction of 53%, for the same structural targets.

Shafts with U-shaped circumferential grooves subjected to internal normal force and bending moment are investigated on the basis of finite element analysis. The classical problem of the stress concentration factors (SCFs) identification is addressed. SCF charts are provided, adopting the maximum equivalent von Mises stress in the SCF definition. The discrepancy between the uniaxial SCFs extracted from the standard reference books and the multiaxial SCF obtained by finite element increases from 5% up to 20%. The intersections between the SCF curves are studied, which reveal a non-monotonic profile of the SCFs with respect to the outer and inner diameter ratio of the notched shaft. The radial displacement at the notch root is examined and design charts of ample validity and prompt access are compiled. It is found that the radial displacement sign and magnitude are largely dependent on the geometry of the notch. Furthermore, the strain and stress state of extremely shallow grooves are analysed, and a critical discussion on their SCFs using the von Mises criterion is presented. The influence of Poisson’s ratio is considered. A simplified method for the evaluation of a multiaxial SCF is proposed to account for the Poisson’s ratio effect. Thanks to the employment of few dedicated diagrams, and the present method allows an accurate evaluation of the SCF for U-grooved shafts, when Poisson’s ratio differs from the common 0.3 value.

Structural engineering in the automotive industry has moved towards weight reduction and passive safety whilst maintaining a good structural performance. The development of Additive Manufacturing (AM) technologies has boosted design freedom, leading to a wide range of geometries and integrating functionally-graded lattice structures. This paper presents three AM-oriented numerical optimization methods, aimed at optimizing components made of: i) bulk material, ii) a combination of bulk material and graded lattice structures; iii) an integration of solid, lattice and thin-walled structures. The optimization methods were validated by considering the steering column support of a mid-rear engine sports car, involving complex loading conditions and shape. The results of the three methods are compared, and the advantages and disadvantages of the solutions are discussed. The integration between solid, lattice thin-walled structures produced the best results, with a mass reduction of 49.7% with respect to the existing component.

BACKGROUND: Spread through air spaces (STAS) has been reported as a negative prognostic factor in patients with lung cancer undergoing sublobar resection. Radiomics has been recently proposed to predict STAS using preoperative computed tomography (CT). However, limitations of previous studies included the strict selection of imaging acquisition protocols, leading to results hardly applicable to daily clinical practice. The aim of this study is to test a radiomics-based prediction model of STAS in a practice-based dataset. METHODS: A training cohort of 99 consecutive patients (65 STAS+ and 34 STAS−) with resected lung adenocarcinoma (ADC) was retrospectively collected. Preoperative CT images were collected from different centers regardless model and scanner manufacture, acquisition and reconstruction protocol, contrast phase and pixel size. Radiomics features were selected according to separation power and P value stability within different preprocessing setups and bootstrapping resampling. A prospective cohort of 50 patients (33 STAS+ and 17 STAS−) was enrolled for the external validation. RESULTS: Only the five features with the highest stability were considered for the prediction model building. Radiomics, radiological and mixed radiomics-radiological prediction models were created, showing an accuracy of 0.66±0.02 after internal validation and reaching an accuracy of 0.78 in the external validation. CONCLUSIONS: Radiomics-based prediction models of STAS may be useful to properly plan surgical treatment and avoid oncological ineffective sublobar resections. This study supports a possible application of radiomics-based models on data with high variance in acquisition, reconstruction and preprocessing, opening a new chance for the use of radiomics in the prediction of STAS. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT04893200.

Background: Pneumothorax can be the first symptom of lymphangioleiomyomatosis. Patients with lymphangioleiomyomatosis have a higher risk of recurrence of pneumothorax. Chemical pleurodesis is a viable option to treat the recurrence, but in rare cases, it is not the solution. Case Presentation: We present the case of a patient with lymphangioleiomyomatosis undergoing a talc poudrage via video-assisted thoracoscopic surgery for pneumothorax that failed to re-expand the lung. We proposed to the patient a surgical approach to debride the lung parenchyma with the patient under deep sedation with spontaneous breathing. The patient was discharged on the 5th postoperative day. The chest computed tomography scan showed complete lung re-expansion. Conclusion: We advocate that video-assisted thoracoscopic surgery in patients who are awake is a feasible surgical option that permits the restoration of physiological lung expansion in selected patients who underwent chemical pleurodesis and minimizes the risk of one-lung ventilation.

Funding Acknowledgements Type of funding sources: None. OBJECTIVES This study aimed to describe the results of a modified sympathicotomy (uniportal VATs with stellate ganglion sparing) for cardiac sympathetic denervation (CSD) in the setting of untreatable ventricular tachycardia. BACKGROUND. CSD, in patients with refractory ventricular tachycardia (VT), is comprehensively recognized as an important treatment option for patients with structural heart disease as well as congenital inherited arrhythmia syndrome. A recent case series demostrated the feasibility of the modified technique. METHODS We consecutively enrolled 8 patients with refractory VT. Baseline demographic, medical, and surgical data as well as arrhythmia outcomes and procedural complications were evaluated. RESULTS A total of 8 patients ( 7 pts NIDCM, 1 pt IDCM with mean age:68+-8 years) were enrolled for the treatment of refractory VT with a modified CSD technique. Mean sympathicotomy length were 7.3 (SD 3) min per side. 3/8 patients underwent monolateral (LCSD) sympathicotomy due to strong adesion in the right pleural cavity. Mean follow up was 13 months (SD 6). No complication occurred during the sympathicotomy. An overall reduction in VT burden and VT number was observed after the CSD despite an in-hospital early recurrence in 3 patients. CONCLUSIONS A modified CSD (sympathicotomy T2–T5) with stellate ganglion sparing and the use of unipolar radiofrequency is feasible, effective, and safe in the setting of untreatable VT. Abstract Figure. VT trend

Introduction After lung transplantation (LTx), infections caused by multidrug-resistant (MDR) bacteria are frequent and difficult to treat. Some new antibiotics seem to be effective in treating these infections. Material and Methods We describe our experience in treatment of Klebsiella pneumoniae MDR and Pseudomonas aeruginosa MDR infections with ceftazidime-avibactam (CEF-AVI) and ceftolozane-tazobactam (CEFT-TAZ) in patients who underwent LTx. Results In 3 patients who underwent double LTx and in 4 patients who underwent single LTx, strains of K. pneumoniae and P. aeruginosa were isolated from bronchoalveolar lavage. All patients showed worsening of respiratory functions, increasing in inflammation indexes, and, in some cases, onset of pulmonary consolidation. P. aeruginosa was treated with CEFT-TAZ for 10 days average (7-15 days) and K. pneumoniae with CEF-AVI for 14 days average (4-24 days). One patient developed a septic state caused by K. pneumoniae, requiring 24 days of therapy. None had shown side effects caused by drugs administration. One patient died after 15 days from lung transplant owing to primary graft dysfunction. Conclusions CEF-AVI and CEFT-TAZ seems to be effective in treatment of infections caused by MDR bacteria after lung transplant.

Pectus excavatum is a chest wall malformation with a strong psychological and aesthetic impact. Rarely, pectus excavatum patients can show respiratory or cardiac symptoms occurring mainly during physical exertion. We report a case of a 34-year-old pregnant woman with a severe degree of pectus excavatum who developed serious cardiovascular disease resulting in spontaneous twin abortion at the twenty-first week of gestation. Cardiovascular disease was resolved after open surgical correction of pectus excavatum. This case shows how a tardive diagnosis and a delayed surgical approach for pectus excavatum can lead to severe consequences.

OBJECTIVES Resection of thymic tumours including the removal of both the tumour and the thymus gland (thymothymectomy; TT) is the procedure of choice and is recommended in most relevant articles in the literature. Nevertheless, in recent years, some authors have suggested that resection of the tumour (simple thymomectomy; ST) may suffice from an oncological standpoint in patients with early-stage thymoma who do not have myasthenia gravis (MG) (non-MG). The goal of our study was to compare the short- and long-term outcomes of ST versus TT in non-MG early-stage thymomas using the European Society of Thoracic Surgeons thymic database. METHODS A total of 498 non-MG patients with pathological stage I thymoma were included in the study. TT was performed in 466 (93.6%) of 498 patients who had surgery with curative intent; ST was done in 32 (6.4%). The completeness of resection, the rate of complications, the 30-day mortality, the overall recurrence and the freedom from recurrence were compared. We performed crude and propensity score-adjusted comparisons by surgical approach (ST vs TT). RESULTS TT showed the same rate of postoperative complications, 30-day mortality and postoperative length of stay as ST. The 5-year overall survival rate was 89% in the TT group and 55% in the ST group. The 5-year freedom from recurrence was 96% in the TT group and 79% in the ST group. CONCLUSION Patients with early-stage thymoma without MG who have a TT show significantly better freedom from recurrence than those who have an ST, without an increase in postoperative morbidity rate.

Invenziona che riguarda un serbatoio a camere multiple con capacità anti-sbattimento e metodo di realizzazione, sviluppato per risolvere problemi di sicurezza e di dinamica.

Korrektur zu 10.1093/ejcts/ezab224

In this practically oriented paper, representative examples of cap failures in a connecting rod are discussed, and deeply dissimilar geometries of the cap cross section are presented. An analytical model of the stresses within a connecting rod cap is developed and satisfactorily validated versus FE (Finite Elements). This model accounts for the effect of the initial clearance between the crankpin surface and the cap intrados, and it realistically mimics the crankpin-cap progressive contact. A load parameter that accounts for the combined effects of several leading variables is analytically derived, on which the following variables depend: a) the contact angular extent between the crankpin and the cap; b) the ratio between the normal and bending stress. This model indicates that the cap bending stress depends on the initial gap between the crankpin and the cap, and not on the applied load. The normal stress within the cap is found to be considerably higher than its bending counterpart. The mechanical response of cap rectangular and ribbed cross sections is compared, and it is found that ribbed sections undesirably increase the cap bending stress. Consequently, the employment of ribs appears to be unjustified from a purely stress related viewpoint.

Lattice materials represent one of the utmost applications of additive manufacturing. The promising synergy between additive processes and topology optimization finds full development in achieving components that comprise bulky and hollow areas, as well as intermediate zones. Yet, the potential to design innovative shapes can be hindered by technological limits. The article tackles the manufacturability by laser-based powder bed fusion (L-PBF) of aluminum-based lattice materials by varying the beam diameter and thus the relative density. The printing accuracy is evaluated against the distinctive building phenomena in L-PBF of metals. The main finding consists in identification of a feasibility window that can be used for development of lightweight industrial components. A relative density of 20% compared with fully solid material (aluminum alloy A357.0) is found as the lowest boundary for a 3-mm cell dimension for a body-centered cubic structure with struts along the cube edges (BCCXYZ) and built with the vertical edges parallel to the growth direction to account for the worst-case scenario. Lighter structures of this kind, even if theoretically compliant with technical specifications of the machine, result in unstable frameworks.

BACKGROUND: Increased age of cancer patients is not an absolute contraindication to pulmonary resection. Different scores have been developed to determine the risk of morbidity and mortality. We have compared four scores in a series of elderly patients with primary or metastatic lung neoplasms who underwent pulmonary resection. METHODS: Data from 150 patients with an age equal or more than 75 years were reviewed. Mean age was 78.3 (range, 75–86) years. Based on medical history and preoperative tests 4 predicting scores were calculated. Statistical analysis was performed to identify which score correlates better with postoperative morbidity and mortality. RESULTS: Mortality at 30 days was observed in 3 patients (2%). Postoperative morbidity was observed in 38 patients (25.3%). Univariate analysis showed that risk factors significantly predicting the onset of postoperative complications were type of resection (P=0.02), American Society of Anesthesiology (ASA) score (P

It is sometimes possible to relieve the stresses in a mechanical component by removing material, where relief grooves are the commonest expedient approach. Within the rectilinear beam realm, rare situations are known in which, by removing material in the cross-sectional zones that are farthest from the neutral axis, a bending stress diminution is achieved. With regard to curved beams, selected examples are presented in which a bending stress diminution is achieved by laterally removing material from the zones close to the neutral axis. An approximate mathematical approach based on Gateaux linearization is developed that delimits the lateral zones of the beam cross-section in which material removal is accompanied by bending stress reduction. While the achievable stress diminution is generally marginal, the reduction of the beam’s cross-section is technically interesting.

A simplified mechanical analysis is carried out for a specific closure system of a pressure vessel, consisting of a segmented locking ring, partially inserted into an annular slot; the ring portion protruding from the slot supports the vessel bottom; sealing is achieved by placing a copper gasket between the ring and the bottom. An approximate contact reaction is assumed, that is formed by a distributed constant linear force and by concentrated forces at the extremities of the ring-slot contact. Analytical expressions of the ring internal forces are provided. A numerical example is presented.

Optimization methods are useful and effective techniques for the design and development of components from the weight reduction point of view. This paper presents an optimization methodology applied to the front cross-member of a Maserati chassis for metal replacement application with the objective of the minimization of the mass of the structure using composite materials. Firstly, a topological optimization of the front side of the vehicle is performed, and the available design space is considered to determine the optimal load path of the design volume and, consequently, to assess a preliminary geometry of the component under scrutiny. Secondly, free-size optimization of the preliminary cross-member design is developed, initially neglecting and subsequently considering the manufacturing constraints. In addition, a linear analysis of the cross-member, modeled as a rigid component, is carried out to evaluate the maximum contribution of this component on the structural performance of the front side of the vehicle. Finally, size and shuffle optimizations are carried out on the new design concept to determine the number and the thickness of the composite plies, and the optimal stacking sequence, respectively, in order to fulfill the structural requirements. A comparison between the new composite structure and the aluminium Maserati cross-member is presented.

A hexagonal joint is mechanically analysed. A cross section of the receding contact between the male and female components is modelled as a plane strain problem. Particular attention is paid to the effect of the presence of fillets in the hexagonal male. Finite Element (FE) results show that, for each side of the hexagonal contact, the contact zone constitutes a small portion of the length of the hexagonal side, and separation occurs elsewhere. The normalized peak contact pressure and the contact length along the male sides are numerically evaluated.

Topology Optimization (TO) methods optimize material layout to design light-weight and high-performance products. However, TO methods, applied for components or assembly with high complexity shape or for structures with copious number of parts respectively, do not usually take into account the manufacturability of the optimized geometries, then a heavy further work is required to engineer the product, risking to compromise the mass reduction achieved. Within an Industry 4.0 approach, we propose to evaluate manufacturing constraints since early stages of the conceptual design to perform a TO coherent with the manufacturing technology chosen. Several approaches of TO with different manufacturing constraints such as casting and extrusion are proposed and each solution is compared. The optimum conceptual design is determined in order to minimize the component weight while satisfying both the structural targets and the manufacturing constraints; a case study on a high-performance sport car dashboard is finally presented.

Bronchial sleeve resection is an uncommon thoracic surgical procedure. Under specific conditions, patients can be selected to undergo a sleeve resection of the main bronchus with complete parenchymal preservation. The left main bronchus is longer than the contralateral bronchus, therefore left endobronchial tumours can be localized at the proximal end of the bronchus or distally, near the secondary carina. Bronchial anastomosis in these 2 situations requires different approaches. We present the surgical technique of left main bronchus resection with complete preservation of lung parenchyma through a hemi-clamshell incision (proximal tumour) or posterolateral thoracotomy (distal tumour).

We describe a rare case of Dirofilaria repens infection presenting as peripheral lung nodules and mimicking a metastatic focus from a previously diagnosed cutaneous melanoma. To avoid invasive investigations before arriving at the correct diagnosis, dirofilariasis should be included as a part of the diagnostic process in subjects with lung nodules who live in (or have traveled to) endemic regions.

Iatrogenic tracheal or tracheobronchial injuries occur after intubation, percutaneous tracheostomy or rigid bronchoscopy. The incidence is relatively rare; however, this complication can potentially be life-threating. We report 13 patients with an iatrogenic tracheal laceration treated between 2011 and 2019 and a literature review to assess the different treatment options. On the base of our experience and the review of the literature surgical treatment remains the gold standard; conservative management is safe in clinically stable patients without complications like pneumomediastinum, mediastinitis or oesophageal laceration.

Background Lung transplantation (LT) is a viable option for a select group of patients with end-stage lung disease. However, infections are a major complication after LT, accounting for significant morbidity and mortality. Several germs may be responsible; multidrug-resistant Gram-negative (MDR-GN) bacteria are emerging. Colistin is widely used in the treatment of these infections and is administered by inhalation and/or parenterally. At our institution, in patients with tracheostomy, colistin is administered by direct instillation in the airway during bronchoscopy. We reviewed a series of patients who underwent LT complicated by postoperative MDR-GN bacterial pulmonary infection. Methods From January 2015 to May 2017, 26 lung transplants were performed. In the postoperative course, 14 (54%) developed MDR-GN bacterial infection; respiratory specimen culture, blood tests, and chest X-ray were considered. Colistin was the only antibiotic usable. Thirteen patients received intravenous (IV) colistin; in the subgroup of patients with tracheostomy, colistin was instilled directly in the airway, and 6 patients received inhaled colistin. Results Seven patients needed tracheostomy. Pseudomonas aeruginosa was the predominant infection (86%), with Acinetobacter baumanii seen in 2 cases (14%). An early clinical-laboratory response was observed in 9 patients (64%). White blood cell count and C-reactive protein values improved (P = .02 and P = .001, respectively). A significant reduction in bacterial load was observed on microbiologic bronchoalveolar lavage specimens. Conclusion Colistin instilled directly in the airway did not show side effects. The combination of IV and inhaled/instilled colistin could be a useful treatment option for MDR-GN infections after LT.

In the last three decades, minimally invasive techniques have progressively gained acceptance, as shown by the numerous studies published in the literature. Before the 1990s, video-assisted thoracoscopic surgery (VATS) was considered feasible almost exclusively for the diagnosis of pleural diseases. The availability of better instruments and endoscopic stapling devices allowed thoracoscopy to evolve into a new “therapeutic era”. Nowadays, VATS is considered the approach of choice for the treatment of pneumothorax and other lung, mediastinal and esophageal diseases, replacing traditional approaches as thoracotomy and sternotomy. The use of ports through small incisions (one to three-four) for the camera and surgical instruments allows the surgeon to explore the pleural cavity and work easily on the lung parenchyma. This approach translates into less discomfort for the patient, reduced morbidity, shorten hospital stay and faster functional recovery. The optimal treatment of pneumothorax certainly refers thoracoscopy as the approach of choice maintaining the same indications as for open surgery.