The Use of Polyvinyl Alcohol Sponge and Cyanoacrylate Glue in the Treatment of Large and Chronic Bronchopleural Fistulae following Lung Cancer Resection.

BACKGROUND: Bronchopleural fistulae represent a relatively rare complication of pulmonary resection. For inoperable patients, several endoscopic procedures have been described. In the presence of large and chronic bronchopleural fistulae, persistent air leaks require a surgical therapy, while endoscopic airway stent represents a useful palliative treatment. OBJECTIVE: We describe the successful closure of large and chronic bronchopleural fistulae using an expandable polyvinyl alcohol (PVA) sponge and cyanoacrylate glue. METHODS: In all patients, a rigid bronchoscope was used to insert a small cylinder of PVA sponge within the fistula. After releasing the patch, cyanoacrylate glue was applied directly on the PVA sponge using a channel catheter. This methodology induces an expansion of the clot and the closure of the air leak. The long-term outcome of treatment was checked by flexible bronchoscopy once every month for 3 months and every 6 months until 5 years. RESULTS: We performed endoscopic treatment in 7 consecutive patients with bronchopleural fistula ranging from 4 to 8 mm. In 6 of 7 patients, the bronchial stump was the site of the fistula. In 1 patient, the fistula was visualized on the right wall of the distal trachea. A temporary complete occlusion of the fistula was achieved in 7 of 7 patients and a definitive result in 5 of 7 patients. CONCLUSIONS: The use of an expandable PVA sponge and cyanoacrylate glue is an available strategy for endobronchial closure of bronchopleural fistulae.

Osmosis process for leachate treatment in industrial platform: Economic and performances evaluations to zero liquid discharge.

The industrial processes require large quantities of water. The presence of discharges results not only in significant environmental impact but implies wastage of water resources. This problem could be solved treating and reusing the produced wastewaters and applying the new zero liquid discharge approach. This paper discusses the design and the performances of reverse osmosis membranes for the upgrading of full scale platform for industrial liquid wastes. The final effluent from the ultrafiltration unit of the full scale plant was monitored to design the reverse osmosis unit. Previous modelling phase was used to evaluate the specific ordinary and maintenance costs and the final effluent quality (2.7 €/m3). The system was designed in triple stages at different operative pressures. The economic feasibility and the payback period of the technology at different percentages of produced permeate were determined. The recovery of 90% was identified as profitable for the reverse osmosis application. One experimental pilot plant applying the reverse osmosis was used to test the final effluent. Moreover, the same flow was treated with second pilot system based on the forward osmosis process. The final efficiencies were compared. Removals higher than 95% using the reverse system were obtained for the main macropollutants and ions. No sustainable applicability of the forward osmosis was determined.

Reduction of Biological Sludge Production Applying an Alternating Oxic/anoxic Process in Water Line.

Alternating oxic/anoxic process, applied for the main objective of the improvement of nitrogen performances, was studied in terms of secondary effect of biomass reduction. The process was carried out in one real water resource recovery facility and the data were compared with the previous conventional period when a conventional process was adopted. The main mechanism of the process for the sludge minimization is recognized in the metabolic uncoupling. In fact, an increase of the specific oxygen uptake rate in the biological reactor was recorded stimulated by the change of the oxidation reduction potential environment. Moreover, the heterotrophic growth yield was measured equal to 0.385 kgVSS/kgCOD. The global percentage of reduction was tested with the mass balance of solids. The process is able to decrease the observed sludge yield up to 20%. The specific energy consumption was evaluated.

Dinitrogen oxide (N2O) emission in the treatment of urban wastewater via nitrite: influence of liquid kinetic rates.

N2O emission was studied in a continuous process via nitrite for real urban wastewater treatment. The relationship between the gaseous forms and the liquid kinetic rates of nitritation and denitritation was investigated. N2O mass load and global nitrogen mass balance were quantified. The emission factor of the N2O (gN2Oemitted/kg mixed liquor volatile suspended solids [MLVSS]/d) was calculated. Incrementing the nitritation rate permits the reduction of N2O emission by 78%. Instead, an N2O decrease of 93% was observed by increasing the denitritation velocity. The determinant role of the anoxic phase in the production of dinitrogen oxide was identified. The contribution of N2O emission from the anoxic phase (4.8 gN2O-N/kgMLVSS/d) was enhanced under limiting denitritation conditions (kd lower than 0.08 kgNOx-N/kgMLVSS/d). N2O production increased by five times with the accumulation of nitrites in the solution up to 200 mg/L. Strict correlation between free ammonia concentration and nitritation rate was found as a possible signal of further ammonia oxidizing bacteria selection.

Reduction of the excess sludge production by biological alternating process: real application results and metabolic uncoupling mechanism.

The biological solution proposed to reduce the wasted sludge production is based on a process of alternating phases realized in a specific reactor (alternate cycles in sludge line (ACSL)) where a quote of the recycle sludge is treated and sent back to the main activated sludge process. The ACSL process was applied in two urban wastewater treatment plants (WWTPs). The reduction was tested by changing the hydraulic retention time and the conditions of oxidation reduction potential. The main mechanism of the process is recognized in the metabolic uncoupling. In fact, an increase in the specific oxygen uptake rate in the biological reactors was recorded (up to 20 mg/g VSS/h), which was stimulated by the fasting condition in the ACSL. The process is able to reduce the observed sludge yield on average of 25-30% with final average values reaching 0.179 kg VSS/kg chemical oxygen demand (COD) for WWTP1 and 0.117 kg VSS/kg COD for WWTP2.

Production of nitrogen oxide gases from an oxic/anoxic process via nitrite: influence of liquid parameters and impact on mass balance.

The produced nitrogen oxides from the biological treatment of swine and dairy anaerobic supernatant are evaluated. The quantification of the emissions has been conducted in a continuous way and coupled with batch tests to determine the mechanisms of formation. Using a continuous monitoring system, N2O and NO forms are present in higher quantities than NO2. The elevated emissions are linked with the increment of the influent nitrogen load both in the daily variations and in the long period. The NH4-N and NO2-N accumulations are recognized as the main parameters which determine the great nitrogen oxide emissions even at dissolved oxygen concentration of around 2 mgL(-1). The nitrogen oxides' impacts are between 0.0034 and 0.0044N% for the N2O and between 0.0020 and 0.0026N% for NO. A strict dependence between the N2O and the oxidation reduction potential is found.

Industrial wastewater platform: upgrading of the biological process and operative configurations for best performance.

The treatment of industrial liquid wastes is placed in a wide context of technologies and is related to the high variability of the influent physical-chemical characteristics. In this condition, the achievement of satisfactory biological unit efficiency could be complicated. An alternate process (AC) with aerobic and anoxic phases fed in a continuous way was evaluated as an operative solution to optimize the performance of the biological reactor in a platform for the treatment of industrial liquid wastes. The process application has determined a stable quality effluent with an average concentration of 25 mg TN L(-1), according to the law limits. The use of discharged wastewaters as rapid carbon sources to support the anoxic phase of the alternate cycle, realizes a reduction of TN of 95% without impact on the total operative costs. The evaluation of the micro-pollutants behaviour has highlighted a bio-adsorption phenomenon in the first reactor. The implementation of the process defined 31% of energy saving during period 1 and 19% for the periods 2, 3 and 4.

Switching small WWTPs from extended to intermittent aeration: process behaviour and performances.

The paper presents the one year results obtained by a small wastewater treatment plant (WWTP) located in a decentralized area. The plant was organized, reusing current structures, introducing an equalization tank, an anoxic selector and the alternate cycles (AC) as technology in the biological process. The experimentation data processed show the excellent quality of the effluent with high removal efficencies for all the macropollutants. Also, the anoxic selector effect allows, in the critical winter period, the decrease in the filamentous bacteria total number, a net improvement of the settling behaviour with an average solid maximum flux value of 3.8 kgMLSSm(-2) h(-1) and a good mixed liquor settleability. The alternate cycles process flexibility consents to well manage the high fluctuations of the influent loadings. The costs comparison of AC process and extended aeration confirms the sustainability of the upgrading.

Role of Transbronchial Needle Core Biopsy in the Diagnosis of Mediastinal Diseases: Experience With an Innovative Endoscopic Technique Using a Rigid Tru-Cut Needle.

BACKGROUND: Enlarged lymph nodes or mediastinal masses diagnosed by computed tomographic scan before the advent of bronchoscopic procedures (TBNA or EBUS) were usually investigated using a thoracic surgical approach. In this paper, we report the experience with the use of a modified rigid tru-cut needle in the bioptical approach to mediastinal masses; to determine whether it could be considered a valid alternative to surgery, we investigated the diagnostic accuracy of this new endoscopic technique. METHODS: A total of 156 selected patients with radiographic evidence of lymphadenopathy or mediastinal masses (subcarinal and paratracheal with a short-axis diameter >3 cm) were studied in our center by rigid bronchoscopy using a 18-G tru-cut needle to obtain a core biopsy of the lesion. RESULTS: In 140 of 156 cases (89.7%), a histologically correct diagnosis was reached without perioperative or postoperative complications. A total of 114 (81.4%) malignant and 26 (18.6%) benign lesions were diagnosed avoiding further invasive surgical approach. CONCLUSIONS: Our results confirm that, in selected cases, transbronchial rigid core biopsy could be considered a safe and valid alternative technique to more invasive surgical approach in the diagnosis of mediastinal diseases.

Application of food waste disposers and alternate cycles process in small-decentralized towns: a case study.

The use of food waste disposers (FWDs) can be an interesting option to integrate the management of municipal wastewaters and household organic waste in small towns and decentralized areas. This strategy can be even more environmentally friendly if a suitable treatment process of the resulting sewage is performed in order to control nutrients emission. However, still nowadays, part of the scientific and technical community considers the application of this technology a possible source of problems. In this study, the FWDs were applied, with a market penetration factor of 67%, in a mountain village of 250 inhabitants. Further, the existing wastewater treatment plant (WWTP) was upgraded by applying an automatically controlled alternate cycles process for the management of nutrients removal. With specific reference to the observed results, the impact of the ground food waste on the sewerage system did not show particular solids sedimentation or significant hydraulic overflows. Further, the WWTP was able to face the overloads of 11, 55 and 2g per capita per day of TSS, COD and TN, respectively. Then, the increase of the readily biodegradable COD (rbCOD/COD from 0.20 to 0.25) and the favourable COD/TN ratio (from 9.9 to 12) led to a specific denitrification rate of some 0.06kgNO(3)-N/(kg MLVSS day). Therefore, not only COD removal, but also the total nitrogen removal increased: the denitrification efficiency reached 85%. That led to a better exploitation of the nitrogen-bound oxygen and a consequent reduction of energy requirements of 39%. The final economic evaluation showed the benefits of the application of this technology with a pay back time of 4-5 years.

Influence of aeration cycles on mechanical characteristics of elastomeric diffusers in biological intermittent processes: Accelerated tests in real environment.

The paper deals with the evaluation of the effect of on/off switching of diffuser membranes, in the intermittent aeration process of the urban wastewater treatments. Accelerated tests were done using two types of commercial EPDM diffusers, which were submitted to several consecutive cycles up to the simulation of more than 8 years of real working conditions. The effect of this switching on the mechanical characteristics of the membranes was evaluated in terms of pressure increment of the air operating at different flow rates (2, 3.5 and 6 m3/h/diff): during accelerated tests, such increment ranged from 2% to 18%. The intermittent phases emphasized the loss both of the original mechanical proprieties of the diffusers and of the initial pore shapes. The main cause of pressure increment was attributed to the fouling of the internal channels of the pores. Further analyses performed by scanning electron microscopy and by mechanical tests on EPDM membrane, using a traditional tensile test and a non destructive optical method, from which the Young's Modulus was obtained, supported previous conclusions. Any changes in terms of oxygen transfer parameters (KLa and SOTE%) were specifically founded by causing to the repeated on/off switching.

A new endoscopic hand drill for management of tracheal stenosis.

Tracheal resection and primary anastomosis is the treatment of choice for the management of benign tracheal stenoses. Rigid endoscopy with laser-assisted mechanical dilatation is an alternative to surgery and helps to improve symptoms and quality of life in patients unfit for surgery. Here, we describe the treatment of a simple web-like stenosis, using a new endoscopic hand drill that was assembled by sharpening the blunt tip of a standard endoscopic cotton applicator. The bronchoscopy was positioned proximally to the stenotic lesion and radial holes were made at 12, 3 and 9 o'clock. The tip of instrument touched the target area of the stenotic scar. The proximal end was handily rotated and the force, applied on the instrument's tip, and the hole was drilled. Next, endoscopic scissors was placed in the drill holes and the stenotic scar was cut. Mechanical dilatation with rigid bronchoscopes of increasing diameters completed the procedure. This procedure was successfully applied in 5 patients with simple benign tracheal stenosis and unfit for surgery. No intraoperative and/or postoperative complications occurred. No recurrence of stenosis was detected after a mean follow-up of 26 ± 2 months.

Endobronchial ultrasound-driven biopsy in the diagnosis of peripheral lung lesions.

STUDY OBJECTIVES: The aim of our study was to compare the diagnostic yield of two bronchoscopic procedures: endobronchial ultrasound-driven transbronchial biopsy (EBUS-TBB) and transbronchial biopsy (TBB) in peripheral pulmonary lesions. DESIGN: Prospective, randomized, blinded study. SETTING: University Hospital of Rome, Italy. PATIENTS AND METHODS: We examined 799 patients with peripheral lung lesions using bronchoscopy. Patients who could undergo a complete clinical diagnostic follow-up (n = 293) were enrolled in the study and randomly assigned to EBUS-TBB or TBB. We performed these two procedures on 221 patients (97 EBUS-TBB and 124 TBB). Patients in whom biopsies were not diagnostic underwent more invasive procedures to obtain a final diagnosis, and a complete follow-up was possible in 206 patients (87 EBUS-TBB and 119 TBB). RESULTS: Lung cancer was diagnosed in 61 patients in the EBUS-TBB group and in 83 patients in the TBB group. Pulmonary diseases other than cancer were diagnosed in 26 patients and 36 patients, respectively. For patients with lung cancer, sensitivity was 0.79 in the EBUS group and 0.55 in the TBB group (p = 0.004), and accuracy was 0.85 and 0.69, respectively (p = 0.007). The analysis of a subset of patients with lesions > 3 cm showed no significant difference in diagnostic ability between the two procedures. In lesions < 3 cm, we found a considerable decline in TBB sensitivity and accuracy (0.31 and 0.50) while EBUS-TBB maintained their diagnostic yield (0.75 and 0.83) [p = 0.0002 and p = 0.001, respectively]. A similar difference was observed when we compared the sensitivity of the two procedures in lesions < 2 cm (0.23 vs 0.71, p < 0.001). CONCLUSIONS: EBUS-TBB can be an important option in the early diagnosis of peripheral lung cancer, especially in small-sized lesions and in patients who are not eligible for surgery.

The Rationale for Treatment of Postresectional Bronchopleural Fistula: Analysis of 52 Patients.

BACKGROUND: Bronchopleural fistulas are a major therapeutic challenge. We have reviewed our experience to establish the best choice of treatment. METHODS: From January 2001 to December 2013, the records of 3,832 patients who underwent pulmonary anatomic resections were retrospectively reviewed. RESULTS: The overall incidence of bronchopleural fistulas was 1.4% (52 of 3,832): 1.2% after lobectomy and 4.4% after pneumonectomy. Pneumonectomy vs lobectomy, right-sided vs left-sided resection, and hand-sewn closure of the stump vs stapling showed a statistically significant correlation with fistula formation. Primary bronchoscopic treatment was performed in 35 of 52 patients (67.3%) with a fistula of less than 1 cm and with a viable stump. The remaining 17 patients (32.7%) underwent primary operation. The fistula was cured with endoscopic treatment in 80% and with operative repair in 88.2%. Cure rates were 62.5% after pneumonectomy and 86.4% after lobectomy. The cure rate with endoscopic treatment was 92.3% in very small fistulas, 71.4% in small fistulas, and 80% in intermediate fistulas. The cure rate after surgical treatment was 100% in small fistulas, 75% in intermediate fistulas, and 100% in very large fistulas. Morbidity and mortality rates were 5.8% and 3.8%, respectively. CONCLUSIONS: The bronchoscopic approach shows very promising results in all but the largest bronchopleural fistulas. Very small, small, and intermediate fistulas with a viable bronchial stump can be managed endoscopically, using mechanical abrasion, polidocanol sclerosing agent, and cyanoacrylate glue. Bronchoscopic treatment can be repeated, and if it fails, does not preclude subsequent successful surgical treatment.

Interventional endoscopy in the management of benign tracheal stenoses: definitive treatment at long-term follow-up.

OBJECTIVE: Interventional bronchoscopy is one of the modalities for palliation and definitive treatment of benign tracheal stenosis. There is however no general agreement on the management of this disease. Aim of this work is to define, in the largest group of patients presented in the literature, what types of tracheal stenosis are amenable to definitive treatment by interventional endoscopy. METHODS: From January 1996 to June 2006 209 consecutive patients (105 men, 104 women) with benign tracheal stenosis were referred to our center. Etiology included 167 post-intubation and 34 cases of post-tracheostomy stenoses, 8 cases of other diseases. The lesions were classified into two groups: simple and complex. All but nine patients underwent interventional procedures (mechanical dilatation, laser photoresection and placement of a silicone stent). Two years follow-up was complete for all patients. RESULTS: Simple stenoses (n=167) were treated by 346 endoscopic procedures (mean of 2.07 per patient), 16 stents and 1 end-to-end anastomosis. Thirty-eight granulomas were treated by 59 procedures (1.56 per patient), 97 concentrical stenoses by 228 procedures (2.35 per patient) and 32 web-like lesions with 59 operative endoscopies (1.84 per patient). Overall success rate was 96%. Among the 42 complex stenoses, 9 were immediately treated by surgical resection and the remaining 33 lesions underwent 123 endoscopic procedures (3.27 per patient), with 34 stents and 1 end-to-end anastomosis subsequent to recurrence after stent removal. In this group the success rate was 69%. CONCLUSIONS: Our study shows that, after a correct classification and stratification, interventional endoscopy may have a crucial role in the treatment of tracheal stenoses. In particular, endoscopy should be considered the first choice for simple stenoses, whereas complex stenoses need a multidisciplinary approach and often require surgery.