Project description:BackgroundEndobronchial valve (EBV) therapy, a validated method for bronchoscopic lung volume reduction (BLVR) in severe emphysema, has been explored for persistent air-leak (PAL) management. However, its effectiveness and safety in the Asian population require further real-world evaluation. In this study, we assessed the outcomes of treatment with EBV within this demographic.MethodsWe conducted a retrospective analysis of medical records from 11 Korean centers. For the emphysema cohort, inclusion criteria were patients diagnosed with emphysema who underwent bronchoscopy intended for BLVR. We assessed these patients for clinical outcomes of chronic obstructive pulmonary disease. All patients with PAL who underwent treatment with EBV were included. We identified the underlying causes of PAL and evaluated clinical outcomes after the procedure.ResultsThe severe emphysema cohort comprised 192 patients with an average age of 70.3 years, and 95.8% of them were men. Ultimately, 137 underwent treatment with EBV. Three months after the procedure, the BLVR group demonstrated a significant improvement in forced expiratory volume in 1 s (+160 mL vs. +30 mL; P = 0.009). Radiographic evidence of lung volume reduction 6 months after BLVR was significantly associated with improved survival (adjusted hazard ratio 0.020; 95% confidence interval 0.038-0.650; P = 0.010). Although pneumothorax was more common in the BLVR group (18.9% vs. 3.8%; P = 0.018), death was higher in the no-BLVR group (38.5% vs. 54.5%, P = 0.001), whereas other adverse events were comparable between the groups. Within the subset of 18 patients with PAL, the predominant causes of air-leak included spontaneous secondary pneumothorax (44.0%), parapneumonic effusion/empyema (22.2%), and post-lung resection surgery (16.7%). Following the treatment, the majority (77.8%) successfully had their chest tubes removed. Post-procedural complications were minimal, with two incidences of hemoptysis and one of empyema, all of which were effectively managed.ConclusionsTreatment with EBV provides substantial clinical benefits in the management of emphysema and PAL in the Asian population, suggesting a favorable outcome for this therapeutic approach.
Project description:BackgroundBronchoscopic lung volume reduction (BLVR) using 1-way endobronchial valves (EBV) has become a guideline treatment in patients with advanced emphysema. Evidence from this minimally invasive treatment derives mainly from well-designed controlled trials conducted in high-volume specialized intervention centres. Little is known about real-life outcome data in hospitals setting up this novel treatment and which favourable conditions are required for a continuous successful program.ObjectivesIn this study, we aim to evaluate the eligibility rate for BLVR and whether the implementation of BLVR in our academic hospital is feasible and yields clinically significant outcomes.MethodA retrospective evaluation of patients treated with EBV between January 2016 and August 2019 was conducted. COPD assessment test (CAT), forced expiratory volume in 1 s (FEV1), residual volume (RV), and 6-min walking test (6MWT) were measured at baseline and 3 months after intervention. Paired sample t tests were performed to compare means before and after intervention.ResultsOf 350 subjects screened, 283 (81%) were not suitable for intervention mostly due to lack of a target lobe. The remaining 67 subjects (19%) underwent bronchoscopic assessment, and if suitable, valves were placed in the same session. In total, 55 subjects (16%) were treated with EBV of which 10 did not have complete follow-up: 6 subjects had their valves removed because of severe pneumothorax (n = 2) or lack of benefit (n = 4) and the remaining 4 had missing follow-up data. Finally, 45 patients had complete follow-up at 3 months and showed an average change ± SD in CAT -4 ± 6 points, FEV1 +190 ± 140 mL, RV -770 ± 790 mL, and +37 ± 65 m on the 6MWT (all p < 0.001). After 1-year follow-up, 34 (76%) subjects had their EBV in situ.ConclusionImplementing BLVR with EBV is feasible and effective. Only 16% of screened patients were eligible, indicating that this intervention is only applicable in a small subset of highly selected subjects with advanced emphysema, and therefore a high volume of COPD patients is essential for a sustainable BLVR program.
Project description:Spontaneous pneumothorax is a rare complication of pneumocystis jirovecii pneumonia. We report a patient with pneumocystis jirovecii pneumonia and therapy-refractory, right-sided pneumothorax due to persistent air leak (PAL) despite prolonged chest tube placement and multiple pleurodesis attempts. Due to the patient's morbidity, we evaluated if the PAL can be sealed by unidirectional endobronchial valves (EBVs). After occlusion of the right upper lobe by a balloon catheter, the air leak flow-rate decreased from 800 ml/min to 250 ml/min. Zephyr EBVs (ZEBVs) were placed in the segmental right upper lobe bronchi and subsequently, a complete resolution of the pneumothorax was noted. During 30 months of follow-up, neither recurrence of pneumothorax nor any adverse events of EBV treatment were noted. We conclude that ZEBV placement might be an effective and well-tolerated treatment option for PAL secondary to pneumocystis jirovecii pneumonia with promising long-term results.
Project description:New microfluidic lab-on-a-chip capabilities are enabled by broadening the toolkit of devices that can be created using microfabrication processes. For example, complex geometries made possible by 3D printing can be used to approach microfluidic design and application in new or enhanced ways. In this paper, we demonstrate three distinct designs for microfluidic one-way (check) valves that can be fabricated using digital light processing stereolithography (DLP-SLA) with a poly(ethylene glycol) diacrylate (PEGDA) resin, each with an internal volume of 5-10 nL. By mapping flow rate to pressure in both the forward and reverse directions, we compare the different designs and their operating characteristics. We also demonstrate pumps for each one-way valve design comprised of two one-way valves with a membrane valve displacement chamber between them. An advantage of such pumps is that they require a single pneumatic input instead of three as for conventional 3D-printed pumps. We also characterize the achievable flow rate as a function of the pneumatic control signal period. We show that such pumps can be used to create a single-stage diffusion mixer with significantly reduced pneumatic drive complexity.
Project description:Persistent air leak (PAL) is a cause of significant morbidity in patients who have undergone lung surgery and those with significant parenchymal lung disease suffering from a pneumothorax. Its management can be complex and challenging. Although conservative treatment with chest drain and observation is usually effective, other invasive techniques are needed when conservative treatment fails. Surgical management and medical pleurodesis have long been the usual treatments for PAL. More recently numerous bronchoscopic procedures have been introduced to treat PAL in those patients who are poor candidates for surgery or who decline surgery. These techniques include bronchoscopic use of sealants, sclerosants, and various types of implanted devices. Recently, removable one-way valves have been developed that are able to be placed bronchoscopically in the affected airways, ameliorating air-leaks in patients who are not candidates for surgery. Future comparative trials are needed to refine our understanding of the indications, effectiveness, and complications of bronchoscopic techniques for treating PAL. The following article will review the basic principles of management of PAL particularly focusing on bronchoscopic techniques.
Project description:The novel coronavirus disease (COVID-19) has resulted in a global pandemic. Recently, COVID-19-related pneumothorax has gained attention because of the associated prolonged hospital stay and high mortality. While most cases of pneumothorax respond well to conservative and supportive care, some cases of refractory pneumothorax with persistent air leaks (PALs) do not respond to conventional therapies. There is a lack of evidence-based management strategies to this regard. We describe the case of a 73-year-old man with COVID-19-related acute respiratory distress syndrome (ARDS) who developed delayed tension pneumothorax with PALs caused by alveolopleural fistulas. Despite chest tube drainage, autologous blood pleurodesis, and endoscopic procedures, the PALs could not be closed, and were complicated by thoracic empyema. Subsequent minimally invasive open-window thoracostomy (OWT) with vacuum-assisted closure (VAC) therapy helped successfully control the refractory PALs. Serial chest computed tomography monitoring was useful for the early detection of the pneumothorax and understanding of its temporal relationship with air-filled lung cysts. Our case provides a new perspective to the underlying cause of refractory pneumothorax with PALs, secondary to COVID-19-related ARDS, and underscores the potential of OWT with VAC therapy as a therapeutic alternative in such cases.
Project description:Rationale: Bronchoscopic lung volume reduction with Zephyr Valves improves lung function, exercise tolerance, and quality of life of patients with hyperinflated emphysema and little to no collateral ventilation.Objectives:Post hoc analysis of patient-reported outcomes (PROs), including multidimensional measures of dyspnea, activity, and quality of life, in the LIBERATE (Lung Function Improvement after Bronchoscopic Lung Volume Reduction with Pulmonx Endobronchial Valves used in Treatment of Emphysema) study are reported.Methods: A total of 190 patients with severe heterogeneous emphysema and little to no collateral ventilation in the target lobe were randomized 2:1 to the Zephyr Valve or standard of care. Changes in PROs at 12 months in the two groups were compared: dyspnea with the Transitional Dyspnea Index (TDI), focal score; the Chronic Obstructive Pulmonary Disease Assessment Test (CAT; breathlessness on hill/stairs); Borg; the EXAcerbations of Chronic pulmonary disease Tool-PRO, dyspnea domain; activity with the TDI, magnitude of task/effort/functional impairment, CAT (limited activities), and the St. George's Respiratory Questionnaire (SGRQ), activity domain; and psychosocial status with the SGRQ, impacts domain, and CAT (confidence and energy).Results: At 12 months, patients using the Zephyr Valve achieved statistically significant and clinically meaningful improvements in the SGRQ; CAT; and the TDI, focal score, compared with standard of care. Improvements in the SGRQ were driven by the impacts and activity domains (P < 0.05 and P < 0.001, respectively). Reduction in CAT was through improvements in breathlessness (P < 0.05), energy level (P < 0.05), activities (P < 0.001), and increased confidence when leaving home (P < 0.05). The TDI measures of effort, task, and functional impairment were uniformly improved (P < 0.001). The EXAcerbations of Chronic Pulmonary Disease Tool (EXACT)-PRO, dyspnea domain, was significantly improved in the Zephyr Valve group. Improvements correlated with changes in residual volume and residual volume/TLC ratio.Conclusions: Patients with severe hyperinflated emphysema achieving lung volume reductions with Zephyr Valves experience improvements in multidimensional scores for breathlessness, activity, and psychosocial parameters out to at least 12 months.Clinical trial registered with www.clinicaltrials.gov (NCT01796392).
Project description:BackgroundA prolonged air leak (PAL) is the most frequent complication after pulmonary resection. This study aimed to assess the safety and efficacy of autologous blood patch pleurodesis (ABPP) to treat PAL.MethodsA prospectively maintained database identified patients with a PAL after pulmonary resection for lung cancer between 2015-2019. In this observational cohort study, clinical data were collected to retrospectively compare patients undergoing ABPP to no ABPP in a propensity-matched analysis. Kaplan Meier estimates and Cox models accounting for inverse probability weighting (IPTW) were used to assess the association of ABPP with each outcome.ResultsOf the 740 patients undergoing lung resection, 110 (15%) were identified as having a PAL at postoperative day (POD) 5. There was no difference between baseline characteristics among those undergoing ABPP (n=34) versus no ABPP (n=76). Propensity-weighted analysis did not reveal a significant association of ABPP treatment with in-hospital complication (P=0.18), hospital length of stay (LOS) (P=0.13), or post-discharge complication (P=0.13). However, ABPP treatment was associated with a lower risk of hospital readmission [P=0.02, hazard ratio (HR) 0.16] and reoperation for air leak or empyema (P=0.05, HR 0.11). Although not statistically significant, the mean chest tube (CT) removal of 11 days for the ABPP group was less than the no ABPP group (16 days) (P=0.14, HR 1.5-2). Those treated with ABPP were less likely to be discharged with a CT (ABPP 7/34, 21% vs. no ABPP 40/76, 53%). There was no statistical difference in empyema development between groups (ABPP 0/34, 0% vs. no ABPP 4/76, 5%, P=0.39, HR 0.24).ConclusionsABPP administration is safe compared to traditional PAL management. In a retrospective propensity-matched analysis, postoperative patients treated with ABPP required less readmission and reoperation for PAL. Larger powered randomized trials may demonstrate the magnitude of benefit from treatment with ABPP.
Project description:One of the desired outcomes of dam decommissioning and removal is the recovery of aquatic and riparian ecosystems. To investigate this common objective, we synthesized information from empirical studies and ecological theory into conceptual models that depict key physical and biological links driving ecological responses to removing dams. We define models for three distinct spatial domains: upstream of the former reservoir, within the reservoir, and downstream of the removed dam. Emerging from these models are response trajectories that clarify potential pathways of ecological transitions in each domain. We illustrate that the responses are controlled by multiple causal pathways and feedback loops among physical and biological components of the ecosystem, creating recovery trajectories that are dynamic and nonlinear. In most cases, short-term effects are typically followed by longer-term responses that bring ecosystems to new and frequently predictable ecological condition, which may or may not be similar to what existed prior to impoundment.