Is chest tube capnography effective in differentiating between true and false air leaks after minimally invasive thoracic surgery?

OBJECTIVE

Air leak (AL) is the most frequent adverse event after thoracic surgery. When AL occurs, the concentration of the principal gas in the pleural space should be similar to that of air exhaled. Accordingly, we tried to develop a new method to identify AL by analyzing pCO2 levels in the air flow from the chest drainage using capnography.

METHODS

This is a prospective observational study of 104 patients who underwent VATS surgery between January 2020 and July 2021. Digital drainage systems were used to detect AL.

RESULTS

Eighty-two patients (79%) had lung resection. Among them, 19 had post-operative day 1 air leaks (median 67 ml/min). AL patients had higher intrapleural CO2 levels (median 24 mmHg) (p < 0.001). Median chest drainage duration was 2 days (range 1.0-3.0). Univariable logistic regression showed a linear and significant association between intrapleural CO2 levels and AL risk (OR 1.26, 95% CI 1.17-1.36, p < 0.001, C index: 0.94). The Univariable Gamma model demonstrated that an elevation in CO2 levels was linked to AL on POD1 (with an adjusted mean effect of 7.006, 95% CI 1.59-12.41, p = 0.011) and extended duration of drainage placement (p < 0.001).

CONCLUSIONS

Intrapleural CO2 could be an effective tool to assess AL. The linear association between variables allows us to hypothesize the role of CO2 in the identification of AL. Further studies should be performed to identify a CO2 cutoff that will standardize the management of chest drainage.

Autologous mesenchymal stromal cells embedded with Tissucol Duo® for prevention of air leak after anatomical lung resection: results of a prospective phase I/II clinical trial with long-term follow-up

BACKGROUND

Prolonged air leak (PAL) is the most frequent complication after pulmonary resection. Several measures have been described to prevent the occurrence of PAL in high-risk patients, however, the potential role of mesenchymal stem cells (MSCs) applied in the parenchymal suture line to prevent postoperative air leak in this setting has not been fully addressed.

OBJECTIVE

To analyse the feasibility, safety and potential clinical efficacy of the implantation of autologous MSCs embedded in Tissucol Duo® as a prophylactic alternative to prevent postoperative prolonged air leak after pulmonary resection in high-risk patients.

STUDY DESIGN

Phase I/II single-arm prospective clinical trial.

METHODS

Six patients with high risk of PAL undergoing elective pulmonary resection were included. Autologous bone marrow-derived MSCs were expanded at our Good Manufacturing Practice (GMP) Facility and implanted (embedded in a Tissucol Duo® carrier) in the parenchymal suture line during pulmonary resection surgery. Patients were monitored in the early postoperative period and evaluated for possible complications or adverse reactions. In addition, all patients were followed-up to 5 years for clinical outcomes.

RESULTS

The median age of patients included was 66 years (range: 55-70 years), and male/female ratio was 5/1. Autologous MSCs were expanded in five cases, in one case MSCs expansion was insufficient. There were no adverse effects related to cell implantation. Regarding efficacy, median air leak duration was 0 days (range: 0-2 days). The incidence of PAL was nil. Radiologically, only one patient presented pneumothorax in the chest X-ray at discharge. No adverse effects related to the procedure were recorded during the follow-up.

CONCLUSIONS

The use of autologous MSCs for prevention of PAL in patients with high risk of PAL is feasible, safe and potentially effective.

TRIAL REGISTRATION NO

EudraCT: 2013-000535-27.

CLINICALTRIALS

gov idenfier: NCT02045745.

A series of experiences with TissuePatch™ for alveolar air leak after pulmonary resection

OBJECTIVES

Prolonged air leak after pulmonary resection strongly influences chest tube duration and hospitalization. This prospective study aimed to report a series of experiences with a synthetic sealant (TissuePatch™) and compare them with a combination covering method (polyglycolic acid sheet + fibrin glue) for air leaks after pulmonary surgery.

METHODS

We included 51 patients (age: 20-89 years) who underwent lung resection. Patients who presented with alveolar air leak during the intraoperative water sealing test were randomly assigned to the TissuePatch™ or combination covering method groups. The chest tube was removed when there was no air leak over a period of 6 h, and no active bleeding under continuous monitoring using a digital drainage system. The chest tube duration was assessed, and various perioperative factors (such as the index of prolonged air leak score) were evaluated.

RESULTS

Twenty (39.2%) patients developed intraoperative air leak; ten patients received TissuePatch™; and one patient who was receiving TissuePatch™ switched to the combination covering method because of broken TissuePatch™. The chest tube duration, index of prolonged air leak score, prolonged air leak, other complications, and postoperative hospitalization in both groups were similar. No TissuePatch™-related adverse events were reported.

CONCLUSIONS

Results from the use of TissuePatch™ were almost similar to those associated with the use of combination covering method in preventing prolonged postoperative air leak after pulmonary resection. Randomized, double-arm studies are required to confirm the efficacy of TissuePatch™ observed during this study.

Intrinsic pulmonary sealing, its mechanisms and impact on validity and translational value of lung sealant studies: a pooled analysis of animal studies

Background

No validated and standardized animal models of pulmonary air leakage (PAL) exist for testing aerostatic efficacy of lung sealants. Lack of negative control groups in published studies and intrinsic sealing mechanisms of healthy animal lungs might contribute to a translational gap, leading to poor clinical results. This study aims to address the impact of intrinsic sealing mechanisms on the validity of PAL models, and investigate the conditions required for an ovine model of PAL for lung sealant testing.

Methods

An ovine acute aerostasis model was developed, consisting of a bilateral thoracotomy with lesion creation, chest tube insertion and monitoring of air leaks using digital drains (≥80 minutes), under spontaneous respiration. Healthy mixed-breed adult female sheep were used and all in vivo procedures were performed under terminal anesthesia. Superficial parenchymal lesions were tested post-mortem and in vivo, extended lesions including bronchioles (deep bowl-shaped and sequential lung amputation lesions) were tested in vivo. Experiment outcomes include air leakage (AL), minimal leaking pressure (MLP) and histology.

Results

Two post-mortem (N=4 superficial parenchymal lesions) and 10 in vivo experiments (N=5 superficial parenchymal and N=16 lesions involving bronchioles) were performed. In contrast to the post-mortem model, superficial parenchymal lesions in vivo showed less air leak [mean flow ± standard deviation (SD): 760±693 vs. 42±33 mL/min, P=0.055]. All superficial parenchymal lesions in vivo sealed intrinsically within a median time of 20 minutes [interquartile range (IQR), 10-75 minutes]. Histology of the intrinsic sealing layer revealed an extended area of alveolar collapse below the incision with intra-alveolar hemorrhage. Compared to superficial parenchymal lesions in vivo, lesions involving bronchioles induced significantly higher air leak post-operatively (normalized mean flow ± SD: 459±221 mL/min, P=0.003). At termination, 5/9 (55.6%) were still leaking (median drain time: 273 minutes, IQR, 207-435 minutes), and intrinsic sealing for the remaining lungs occurred within a median of 115 minutes (IQR, 52-245 minutes).

Conclusions

Lung parenchyma of healthy sheep shows a strong intrinsic sealing mechanism, explained pathologically by an extended area of alveolar collapse, which may contribute to a translational gap in lung sealant research. A meaningful ovine model has to consist of deep lesions involving bronchioles of >⌀1.5 mm. Further research is needed to develop a standardized PAL model, to improve clinical effectiveness of lung sealants.

Sealing effectiveness of a novel NHS-POx based patch: experiments in a dynamic ex vivo porcine lung

Background

Sealants are used to prevent prolonged pulmonary air leakage (PAL) after lung resections (incidence 5.6-30%). However, clinical evidence to support sealant use is insufficient, with an unmet need for a more effective product. We compared a novel gelatin patch impregnated with functionalized polyoxazolines (NHS-POx) (GATT-Patch) to commercially available sealant products.

Methods

GATT-Patch Single/Double layers were compared to Progel®, Coseal®, Hemopatch® and TachoSil® in an ex vivo porcine lung model (first experiment). Based on these results, a second head-to-head comparison between GATT-Patch Single and Hemopatch® was performed. Air leakage (AL) was assessed in three settings using increasing ventilatory pressures (max =70 cmH2O): (I) baseline, (II) with 25 mm × 25 mm superficial pleural defect, and (III) after sealant application. Lungs floating on saline (37 ℃) were video recorded for visual AL assessment. Pressure and tidal volumes were collected from the ventilator, and bursting pressure (BP), AL and AL-reduction were determined.

Results

Per sealant 10 measurements were performed (both experiments). In the first experiment, BP was superior for GATT-Patch Double (60±24 cmH2O) compared to TachoSil® (30±11 cmH2O, P<0.001), Hemopatch® (33±6 cmH2O, P=0.006), Coseal® (25±13 cmH2O, P=0.001) and Progel® (33±11 cmH2O, P=0.005). AL-reduction was superior for GATT-Patch Double (100%±1%) compared to Hemopatch® (46%±50%, P=0.010) and TachoSil® (31%±29%, P<0.001), and also for GATT-Patch Single (100%±14%, P=0.004) and Progel (89%±40%, P=0.027) compared to TachoSil®. In the second experiment, GATT-Patch Single was superior regarding BP (45±10 vs. 40±6 cmH2O, P=0.043) and AL-reduction (100%±11% vs. 68%±40%, P=0.043) when compared to Hemopatch®.

Conclusions

The novel NHS-POx patch shows promise as a lung sealant, demonstrating elevated BP, good adhesive strength and a superior AL-reduction.

A panoramic view of a cohort of obstructive sleep apnea patients on positive airway pressure therapy using cloud based telemonitoring devices

Background

Positive airway pressure therapy is mainstay of treatment of obstructive sleep apnea (OSA). But long-term compliance with is poor with such therapy. A proactive and vigilant management may improve the PAP therapy usage. Cloud-based telemonitoring PAP devices offer an opportunity for proactive monitoring and prompt interventions related to PAP troubleshooting. This technology is also used in India for adult OSA patients. But we lack our own data on behavior of Indian patients as a cohort on PAP therapy. The present study is an attempt to look at the behavior a cohort of PAP users in OSA.

Methodology

This study was planned as a retrospective analysis of data of OSA patients who were using a cloud-based PAP devices. First 100 patients were chosen for data retrieval that who was on this therapy. The data was obtained for those patients who were on PAP for at least 7 days and maximum follow-up was available up to 390 days. Descriptive statistical analysis has been carried out in the present study.

Results

The number of male and female patients was 75 and 25, respectively. Overall good compliance was present in 66% of patients. 34% of patients were not compliant with PAP during follow-up. The compliance was statistically same in both the sexes (P = 0.8088). Incomplete data recovery was present in 17 patients and 11 (64.70%) were non-compliant among them. In the initial, 60 days non-compliant patients were more than compliant patients. The difference was lost in 60 to 90 days of use. The air leak was present more in the compliant group than non-compliant group (P = 0.0239). 75.75% of compliant patients had achieved AHI control, whereas 35.29% of non-compliant patients also achieved AHI control. But overall, AHI control was poor in non-compliant patients and 61.76% of non-compliant patients had an AHI uncontrolled.

Conclusions

We conclude that 3/4th of the compliant patients achieve AHI control while 1/4th didn't. This 1/4th population needs further exploration to determine the causes of poor AHI control. Cloud-based PAP devices give an easy opportunity to monitor patients of OSA. It gives an instant panoramic view of behavior of OSA patients on PAP therapy. The compliant patients can be tracked, and non-compliant patients can be segregated quickly.

Prolonged air leak after robotic lung resection: a narrative review

Background and Objective

Prolonged air leak (PAL) following lung resection is related to an increase in morbidity and both direct and indirect costs. In recent years, robotic-assisted thoracic surgery (RATS) has proved to be a safe technique with comparable perioperative outcomes of video-assisted thoracic surgery (VATS), optimal oncological results, and potential advantages in case of sublobar resection. We here focus on the incidence and clinical impact of PAL in the field of robotic surgery and discuss the therapeutic strategies currently available.

Methods

We conducted a search on PubMed/MEDLINE and Scopus database from inception until May 27^th 2022 to select the relevant literature published in English exploring the occurrence of PAL following RATS.

Key Content and Findings

The implementation of robotic surgery led to a significant reduction in PAL occurrence after pulmonary resection compared to open thoracotomy, while there is still no clear advantage with respect to VATS. However, the enhanced dexterity and improved visualization of the robot seem to particularly valuable in case of sublobar lung resection, especially complex ones. Accurate selection of patients based on the presence of risk factors allows the implementation of intraoperative measures in order to reduce the occurrence of PAL.

Conclusions

Robotic lung resection is a safe technique, advantageous compared to traditional open thoracotomy in terms of PAL occurrence reduction and it is a valid alternative to manual VATS. Moreover, with the extension of indications for sublobar resection in the treatment of early stage lung cancer, RATS may prove to be the technique of choice thanks to its intrinsic advantages.

Air leaks in COVID-19

Coronavirus disease 2019 (COVID-19) continues to create havoc and may present with myriad complications involving many organ systems. However, the respiratory system bears the maximum brunt of the disease and continues to be most commonly affected. There is a high incidence of air leaks in patients with COVID-19, leading to acute worsening of clinical condition. The air leaks may develop independently of the severity of disease or positive pressure ventilation and even in the absence of any traditional risk factors like smoking and un-derlying lung disease. The exact pathophysiology of air leaks with COVID-19 remains unclear, but multiple factors may play a role in their development. A significant proportion of air leaks may be asymptomatic; hence, a high index of suspicion should be exercised for enabling early diagnosis to prevent further deterioration as it is associated with high morbidity and mortality. These air leaks may even develop weeks to months after the disease onset, leading to acute deterioration in the post-COVID period. Conservative management with close monitoring may suffice for many patients but most of the patients with pneumothorax may require intercostal drainage with only a few requiring surgical interventions for persistent air leaks.

Risk factors for prolonged air leak and need for intervention following lung resection

OBJECTIVES

Prolonged air leak (PAL; >5 days) following lung resection is associated with postoperative morbidity. We investigated factors associated with PAL and PAL requiring intervention.

METHODS

Retrospective review of all patients undergoing lobectomy, segmentectomy or wedge resection from 2016 to 2019 at our institution. Bronchoplastic reconstructions and lung-volume reduction surgeries were excluded. Incidence and risk factors for PAL and PAL requiring intervention were evaluated.

RESULTS

In total, 2384 patients were included. PAL incidence was 5.4% (129/2384); 22.5% (29/129) required intervention. PAL patients were more commonly male (56.6% vs 39.7%), older (mean age 69 vs 65 years) and underwent lobectomy or thoracotomy (all P < 0.001). Patients with PAL had longer length of stay (9 vs 3 days), more discharge needs and increased odds of complication (all P < 0.050).Twenty-nine patients required intervention (9 chest tubes; 4 percutaneous drains; 16 operations). In 50% of operative interventions, an air leak source was identified; however, the median time from intervention to resolution was 13 days. Patients requiring intervention had increased steroid use, lower diffusion capacity for carbon monoxide and twice the length of stay versus PAL patients (all P < 0.050).On univariable analysis, forced expiratory volume in 1 s (FEV1) <40%, diffusion capacity for carbon monoxide <50%, steroid use and albumin <3 had increased odds of intervention (P < 0.050).

CONCLUSIONS

Age, gender and operative technique were related to PAL development. Patients with worse forced expiratory volume in 1 s or diffusion capacity for carbon monoxide, steroid use or poor nutrition were less likely to heal on their own, indicating a population that could benefit from earlier intervention.

Risk Factors, Clinical Characteristics, and Outcome of Air Leak Syndrome in COVID-19: A Systematic Review

Introduction

Air leak consisting of pneumothorax, pneumomediastinum, and subcutaneous emphysema has been described as one of the complications of coronavirus disease-2019 (COVID-19) infection affecting disease course and outcome. We aimed to conduct a systematic review of published literature to highlight the risk factors, types, and outcomes in COVID-19.

Method

A systematic search of PubMed, Embase, Scopus, and Google Scholar was performed from November 1, 2019, to February 28, 2021. Seventy-one studies fulfilled the inclusion criteria and 136 adult patients were included in the final analysis.

Results

Majority of patients were male (75.2%) with the mean age of 58 years. Hypertension was the most common comorbidity followed by diabetes mellitus. Moreover, 12.5% of patients had a history of smoking while 11.7% had preexisting lung disease. Isolated pneumothorax (48.5%) was the most common and 17.65% had developed spontaneous pneumothorax. Mean onset time was 11.6 days and 67% of patients required an intercostal drainage tube for management. Mortality was 40%, and elderly, female gender, obese and hypertensive were at higher risk.

Conclusion

COVID-19-related air leaks are associated with higher mortality and longer hospital stay and can occur even without positive pressure ventilation. History of smoking and preexisting lung disease has not been shown to increase the incidence of air leak. A well-designed study is required for a better understanding of COVID-19-related air leak.

How to cite this article

Singh A, Singh Y, Pangasa N, Khanna P, Trikha A. Risk Factors, Clinical Characteristics, and Outcome of Air Leak Syndrome in COVID-19: A Systematic Review. Indian J Crit Care Med 2021;25(12):1434–1445.

Airway injury and pneumomediastinum associated with less invasive surfactant administration in a premature neonate: a case report

Background

The use of less invasive surfactant administration (LISA)/minimally invasive surfactant therapy (MIST) has increased due to its potential advantage over traditional surfactant delivery methods through an endotracheal tube. Known complications for this procedure include failure of the first attempt at insertion, desaturation, and bradycardia. To the best of our knowledge, this is the first reported case of pneumomediastinum and subcutaneous emphysema following LISA.

Case presentation

A preterm newborn born at 27 weeks of gestation presented with respiratory distress syndrome requiring surfactant replacement. LISA using the Hobart method was completed. There was a report of procedural difficulty related to increased resistance to insertion of the 16G angiocath. The newborn was subsequently noted to have subcutaneous emphysema over the anterior aspect of the neck and substantial pneumomediastinum on radiological assessment. Associated complications included hypotension requiring inotropic support. The newborn was successfully managed conservatively, with complete resolution of the air leak.

Conclusions

Upper airway injury leading to air leak syndrome is a rare complication of the Hobart method for LISA. Awareness of such procedural complications is important as the use of the LISA method increases.

Air leaks: Stapling affects porcine lungs biomechanics

During thoracic operations, surgical staplers resect cancerous tumors and seal the spared lung. However, post-operative air leaks are undesirable clinical consequences: staple legs wound lung tissue. Subsequent to this trauma, air leaks from lung tissue into the pleural space. This affects the lung's physiology and patients' recovery. The objective is to biomechanically and visually characterize porcine lung tissue with and without staples in order to gain knowledge on air leakage following pulmonary resection. Therefore, a syringe pump filled with air inflates and deflates eleven porcine lungs cyclically without exceeding 10 cmH₂O of pressure. Cameras capture stereo-images of the deformed lung surface at regular intervals while a microcontroller simultaneously records the alveolar pressure and the volume of air pumped. The raw images are then used to compute tri-dimensional displacements and strains with the Digital Image Correlation method (DIC). Air bubbles originated at staple holes of inner row from exposed porcine lung tissue due to torn pleural on costal surface. Compared during inflation, left upper or lower lobe resections have similar compliance (slope of the pressure vs volume curve), which are 9% lower than healthy lung compliance. However, lower lobes statistically burst at lower pressures than upper lobes (p-value<0.046) in ex vivo conditions confirming previous clinical in vivo studies. In parallel, the lung deformed mostly in the vicinity of staple holes and presented maximum shear strain near the observed leak location. To conclude, a novel technique DIC provided concrete evidence of the post-operative air leaks biomechanics. Further studies could investigate causal relationships between the mechanical parameters and the development of an air leak.

A rare case of persistent air leak: beware of all the tubes

Background

Patients with acute respiratory failure, impaired consciousness, and impaired airway reflexes will require invasive mechanical ventilation. Monitoring of such patients is important. The use of ventilator scalars and loops help in monitoring, diagnosing the abnormality, and treating the patients effectively. We report a rare cause one should suspect in a case of persistent and fixed air leak in a patient requiring mechanical ventilation.

Case presentation

We describe a 28-year-old young patient requiring ventilator support due to neuromuscular weakness. His neuromuscular weakness was rapidly progressing involving the respiratory muscles. The patient was intubated and put on mechanical ventilator support. He was transferred from another health care center to our hospital. On evaluation, the patient was intubated with ETT no 8. The patient had persistent air leak as observed on the ventilator graphics. We checked for ETT cuff malfunction, ventilator circuit, catheter mount, and HME for any disconnection causing the leak. The air leak which we observed in our patient was due to the malpositioned Ryle’s tube.

Conclusions

Vigilant monitoring of patients requiring mechanical ventilation is necessary. For the evaluation of the cause of air leak, algorithmic approach will help in correctly identifying the abnormality.

Efficacy of a Novel Medical Adhesive for Sealing Lung Parenchyma: An in vitro Study in Rabbit Lungs

INTRODUCTION

During thoracic resection procedures, complete hemostasis and aerostasis are priorities. A persistent alveolar air leak is associated with increased morbidity and mortality rates. This study aimed to evaluate whether the novel medical adhesive VIVO (Adhesys Medical GmbH Aachen, Germany) is a reliable alternative sealing technique to routine surgical procedures.

METHODS

We conducted an in vitro animal study by analyzing 21 lungs of New Zealand (n = 19) and Chinchilla Bastard (n = 2) rabbits (age, 11-18 weeks; weight, 2,400-3,600 g). Three groups, each comprising 7 animals, were evaluated. VIVO (VIVO-group) was compared with standard surgical lung parenchymal lesion closure with a polypropylene suture (Suture-group) and TachoSil® (TachoSil-group). We adopted a stable, pressure-controlled ventilation protocol. After explantation, a surgical incision 0.5-cm deep and 1.5-cm wide was made in the lungs using a customized template. Air leak was measured quantitatively (mL/min) using a respirator and visualized qualitatively by 2 observers who made independent judgments. Next, the leak was closed using VIVO, suture, or TachoSil® as specified by the manufacturer. Subsequently, positive end-expiratory pressure (PEEP) and inspiratory pressure were gradually increased until a maximum of 15 and 30 mbar were attained, respectively.

RESULTS

At PEEPs of 8, 10, and 15 mbar, VIVO achieved complete sealing of the profound parenchymal defect in all (n = 7) lungs. After closure of the incision, we observed an air leak variation of 127 ± 114 mL/min (Suture-group), 31 ± 49 mL/min (VIVO-group), and 114 ± 134 mL/min (TachoSil-group). VIVO showed a significantly lower air leak than surgical sutures (p = 0.031) and TachoSil® (p = 0.046).

CONCLUSION

VIVO offers sufficient closure of the lung parenchymal lesions. The novel adhesive enabled significantly better sealing with lower persistent air leakage than TachoSil® or surgical sutures. Further investigation using in vivo models is strongly encouraged to confirm our findings.

Postoperative Air Leaks After Lung Surgery: Predictors, Intraoperative Techniques, and Postoperative Management

Postoperative air leak is one of the most common complications after pulmonary resection and contributes to postoperative pain, complications, and increased hospital length of stay. Several risk factors, including both patient and surgical characteristics, increase the frequency of air leaks. Appropriate intraoperative tissue handling is the most important surgical technique to reduce air leaks. Digital drainage systems have improved the management of postoperative air leak via objective data, portability, and ease of use in the outpatient setting. Several treatment strategies have been used to address prolonged air leak, including pleurodesis, blood patch, placement of endobronchial valves, and reoperative surgery.

Treatment of air leakage using the VIO soft coagulation system: a mouse pulmonary air leak model

PURPOSE

We aimed to compare the efficacy of the VIO soft coagulation system (VSCS) for the treatment of air leaks by sealing with fibrin glue, and also assess the histological alterations that occur after soft coagulation.

METHODS

A mouse pulmonary air leak model was designed. The pulmonary fistula was subsequently coagulated with the VSCS or sealed with fibrin glue with polyglycolic acid (PGA) sheets. The burst pressure at air leak recurrence was measured in each group, and the results were compared. We also evaluated the histological alterations in the mouse pulmonary air leak model after soft coagulation with the VSCS.

RESULTS

The burst pressure in the soft coagulation group (80 W/Effect 5) (median 42.8; range 35.4-53.8 cmH₂O) was similar to that in the fibrin glue group (median 41.5; range 34.6-43.9 cmH₂O) (p = 0.21). Histological examinations revealed that the visceral pleura remained torn, the structure of the pulmonary alveolus was maintained, and the coagulated fistula was covered with a fibrin membrane in the soft coagulation group.

CONCLUSIONS

The pressure resistance following soft coagulation was equivalent to that after sealing using fibrin glue with PGA sheets. The air leaks were likely controlled by covering the fistula with a fibrin membrane after soft coagulation with the VSCS.

A combined management with vv-ECMO and independent lung ventilation for asymmetric chest trauma

Association of independent lung ventilation (ILV) and veno-venous extracorporeal membrane oxygenation (vv-ECMO) may be life-saving therapy in cases of refractory hypoxemia. We report the case of a trauma patient affected by asymmetric hypoxemic lung contusions and massive air leak managed by association of ILV and vv-ECMO. This combined strategy allowed us first to restore physiologic conditions and later to achieve safe thoracic surgery with reduced resection of pulmonary parenchyma. This case highlights the success of a new damage control strategy in extreme cases of persistent air leak with refractory hypoxemia allowing initial vital rescue and a more conservative treatment.

Simulation and Measurement of Aerosolisation in Different Chest Drainage Systems

The aim of the study was to assess the degree of aerosolisation in different chest drainage systems according to different air leak volumes, in a simulated environment. This novel simulation model was designed to produce an air leak by passing air through and agitating a fluorescent fluid. The air leak volume and amount of fluorescent fluid were tested in various combinations and aerosolisation was assessed at 10-minute intervals using the ultraviolet light. The following chest drainage systems were compared: (1) single-chamber chest drainage system, (2) 3-compartment wet-dry suction chest drainage system, (3) digital drainage and monitoring system. The impact of suction (−2 and −4 kPa) in generating aerosolised particles was tested as well. A total number of 187 of 10-minute interval measurements were performed. The single-chamber chest drainage system generated the largest number of aerosolised particles at different air leak volumes and drainage output. The 3-compartment wet-dry suction system and the digital drainage and monitoring system did not generate any identifiable aerosolised particles at any of the air leak or drain output volumes considered. Suction applied to the chest drainage systems did not have an effect on aerosolisation. Aerosol generation in the simulated air-leak model demonstrated the potential risk of SARS-CoV-2 spread in the clinical setting. Full personal protective equipment must be used in patients with an air leak. Single-chamber chest drainage system generates the highest rate of aerosolised particles and it should not be used as an open system in patients with an air leak.

Prolonged air leak after IPC insertion: An unusual complication

Indwelling pleural catheters [IPC] have an important role in the management of malignant pleural effusions. We report the development of a significant air leak following IPC insertion with resultant extensive subcutaneous emphysema. The air leak developed, presumably, as a result of visceral pleural disruption, which occurred at the time of vacuum drainage of pleural fluid after IPC placement and not due to lung injury during insertion. The patient required insertion of a large bore intercostal drain connected to low-pressure negative suction. He was eventually discharged home with the aid of an ambulatory system. Although commonly seen in the surgical setting, we believe emergency and respiratory physicians should be aware of the risk of such a complication, and the challenges in its management.

Management of Complications After Lung Resection: Prolonged Air Leak and Bronchopleural Fistula

Prolonged air leak or alveolar-pleural fistula is common after lung resection and can usually be managed with continued pleural drainage until resolution. Further management options include blood patch administration, chemical pleurodesis, and 1-way endobronchial valve placement. Bronchopleural fistula is rare but is associated with high mortality, often caused by development of concomitant empyema. Bronchopleural fistula should be confirmed with bronchoscopy, which may allow bronchoscopic intervention; however, transthoracic stump revision or window thoracostomy may be required.

Radiologically Guided Management of Secondary Spontaneous Pneumothorax

Secondary spontaneous pneumothorax is a serious medical condition that typically occurs in patients with an underlying lung pathology such as chronic obstructive pulmonary disease. Those patients are usually compromised and more amenable to higher morbidity and mortality rates. Moreover, they are poor candidates for general anesthesia and mechanical ventilation due to their poor health condition. We report a case of an 86-year-old male, who presented with a non-ST-elevation myocardial infarction and was incidentally found to have secondary spontaneous pneumothorax on a routine chest x-ray. The results of his blood work, international normalized ratio and liver function test were abnormal. Therefore, a novel intervention was introduced to control the air-leak by injecting a sealant material (Progel™, Warwick, Rhode Island, USA) through a thoracostomy tube guided by computed tomography fluoroscopy. The procedure was demonstrated to be a successful method of air-leak repair with minimal complications; as the patient was followed for two and a half years without any evidence of recurrence.

Ventilator- and interface-related factors influencing patient-ventilator asynchrony during noninvasive ventilation

Patient-ventilator asynchrony (PVA) is common in patients receiving noninvasive ventilation (NIV). This occurs primarily when the triggering and cycling-off of ventilatory assistance are not synchronized with the patient's inspiratory efforts and could result in increased work of breathing and niv failure. In general, five types of asynchrony can occur during NIV: ineffective inspiratory efforts, double-triggering, auto-triggering, short-ventilatory cycling, and long-ventilatory cycling. Many factors that affect PVA are mostly related to the degree of air leakage, level of pressure support, and the type and properties of the interface used. Careful monitoring and adjustment of these factors are essential to reduce PVA and improve patient comfort. In this article, we discuss the machine and interface-related factors that influence PVA during NIV and its effect on the respiratory mechanics during pressure support ventilation, which is the ventilatory mode used most commonly during NIV. For that, we critically evaluated studies that assessed ventilator- and interface-related factors that influence PVA during NIV and proposed therapeutic solutions.

Novel air leak test using surfactant for lung surgery

Background

Prolonged air leak is the most common complication after pulmonary resection surgery. Water submersion test (WST) has been used to check for air leak. However, it is cumbersome under the circumstances of video-assisted thoracic surgery (VATS). This study aimed to devise a new air leak detection method that is suitable for the VATS.

Methods

We decided to utilize the properties of the surfactants to overcome the disadvantages of WST. To find the optimal surfactant, ex-vivo porcine lung experiments were prepared with a custom-made large glass vessel mimicking a human thoracic cavity. A fresh lung was put inside the glass vessel and connected with the ventilator. We made a needle injury on the lung surface and dropped various kinds of liquid surfactants to create air bubbles during the lung ventilation. The appearances of bubbles were recorded through 5mm thoracoscope.

Results

Considering the bubble forming ability, Pluronic F-127 solution (PF127), a well-known non-toxic and non-ionic colorless surfactant, was chosen as candidate substance. To find the optimal condition, various concentrations of PF127 (30%, 25%, 20%, 15%, 10%) were tested. Greater than 20% concentration of PF127 were not feasible due to its high viscosity; the bubbles kept increasing in size without popping and blocked the thoracoscopic vision. The 10% PF127 did not form any bubbles. On the contrary, the 15% PF127 formed bubbles that are 1-2 cm in size with dynamic movement allowing for clear visibility of the air leak point. We finally made a green colored 15% PF127 by mixing an indocyanine green to increase its visibility. All of the components in the solution are FDA approved and permissible to be used in the human body.

Conclusions

Our bubble solution can easily detect the air leak even in small quantities and is expected to be useful in VATS with limited vision. However, in order for its full-scale clinical use, its safety in the human body must be verified.

Air leak pattern shown by digital chest drainage system predict prolonged air leakage after pulmonary resection for patients with lung cancer

Background

A common cause of complications after a pulmonary resection procedure is prolonged air leakage. Recently introduced digital drainage systems provide accurate recording of air leak data for later review. We investigated the clinical usefulness of the continuous stream of data recorded by such a device.

Methods

We analyzed data obtained from 299 patients with pulmonary malignancy who underwent a pulmonary resection procedure for lung cancer patients with use of a digital chest drainage system. Postoperative air leak patterns were divided into 4 groups and their correlation with prolonged air leakage after pulmonary resection was evaluated.

Results

The incidence of prolonged air leak was 10% (30/299). The postoperative air leak patterns noted in the present patients were divided into none (n=217, 73%), intermittent (n=21, 7%), decrease (n=40, 13%), and variable (n=21, 7%). The incidence of prolonged air leak in each group was 0.5% (1/217) in the none group, 24% (5/21) in the intermittent group, 20% (8/40) in the decrease group, and 76% (16/21) in the variable group. The amount of air leakage immediately after surgery was highest in the variable group. Patients in the intermittent and variable groups had longer durations of air leakage and chest tube placement. The frequency of postoperative interventional treatment was significantly higher in the variable group as compared to the others. Chest tube reinsertion for pneumothorax and increased subcutaneous emphysema after the initial chest tube removal was only seen in the intermittent group.

Conclusions

Advantages of digital drainage system use are continuous monitoring and recording capabilities, which show the detailed air leak pattern after pulmonary resection. That pattern can be used to predict the durations of air leakage and chest tube drainage, as well as for producing an air leak management algorithm.

Pressure-decay testing of pleural air leaks in intact murine lungs: evidence for peripheral airway regulation

The critical care management of pleural air leaks can be challenging in all patients, but particularly in patients on mechanical ventilation. To investigate the effect of central airway pressure and pleural pressure on pulmonary air leaks, we studied orotracheally intubated mice with pleural injuries. We used clinically relevant variables - namely, airway pressure and pleural pressure - to investigate flow through peripheral air leaks. The model studied the pleural injuries using a pressure-decay maneuver. The pressure-decay maneuver involved a 3 sec ramp to 30 cmH2 0 followed by a 3 sec breath hold. After pleural injury, the pressure-decay maneuver demonstrated a distinctive airway pressure time history. Peak inflation was followed by a rapid decrease to a lower plateau phase. The decay phase of the inflation maneuver was influenced by the injury area. The rate of pressure decline with multiple injuries (28 ± 8 cmH2 0/sec) was significantly greater than a single injury (12 ± 3 cmH2 O/sec) (P < 0.05). In contrast, the plateau phase pressure was independent of injury surface area, but dependent upon transpulmonary pressure. The mean plateau transpulmonary pressure was 18 ± 0.7 cm H2 O. Finally, analysis of the inflation ramp demonstrated that nearly all volume loss occurred at the end of inflation (P < 0.001). We conclude that the air flow through peripheral lung injuries was greatest at increased lung volumes and limited by peripheral airway closure. In addition to suggesting an intrinsic mechanism for limiting flow through peripheral air leaks, these findings suggest the utility of positive end-expiratory pressure and negative pleural pressure to maintain lung volumes in patients with pleural injuries.

Use of Bioglue™ to seal a difficult to treat air leak in a complicated empyema patient

Surgical sealants have been used in thoracic surgery in an effort to reduce air leak duration, intercostal drain duration, length of stay and complications. They are instilled over a defect usually treated with other means. We herein present the technique of controlling a difficult to treat defect by directly instilling Bioglue™ alone into a crater, caused during empyema Video-assisted thoracic surgery in a 50-year-old patient with a trapped lung. This deep crater had caused a significant air leak rendering intraoperative ventilation challenging. After instillation, the dependent lung was kept blocked. With this technique, the Bioglue™ polymerized and the air leak was dramatically decreased making ventilation and eventually extubation of the patient feasible. Instillation of Bioglue™ directly into a large lung defect could be a choice of action to decrease complicated air leaks, otherwise impossible to treat with other means, in patients with trapped lung.

Can a standardised Ventilation Mechanical Test for quantitative intraoperative air leak grading reduce the length of hospital stay after video-assisted thoracoscopic surgery lobectomy?

We standardised a Ventilation Mechanical Test (VMT) after video-assisted thoracoscopic surgery (VATS) lobectomy that classifies intraoperative alveolar air leaks (IOAALs) in mild, moderate and severe. We assumed that mild IOAALs (<100 mL/min) are self-limiting, whereas severe IOAALs (>400 mL/min) must be treated. An IOAAL between 100 and 400 mL/min was defined moderate and constituted the study population of a prospective multicentre randomised trial on the use of a polymeric biodegradable sealant (Progel^TM Pleural Air Leak Sealant, Bard Davol, USA) in case of moderate IOAAL compared with no treatment. We assumed that the standardised VMT allows to accurately selected patients needing treatment, thus limiting unnecessary sealant use. We analysed data of the randomised trial to assess the cost-effectiveness of Progel treatment in VMT selected patients. This is a multicenter randomised controlled trial. Patients with moderate IOAAL were randomised to Progel (group A) or "no treatment" (group B).The primary efficacy endpoint of the study was the postoperative duration of air leakage. The secondary outcome measures included: mean time to chest drain removal, mean length of hospitalisation, the percentage of postoperative complications occurring within two months, and cost of treatment. Between January 2015 and January 2017, 255 VATS lobectomies were performed in 4 centres, 55 met the inclusion criteria, and they were randomly assigned to 2 different groups (28 in the Progel and 27 in the control group). The mean air leakage duration was statistically different between the two groups: in the group A was 1.60 vs. 5.04 days in group B (P<0.001). The average duration of chest drainage was statistically shorter in group A than in the control group (4.1 vs. 6.74 days; P=0.008). The mean time to hospital discharge was also statistically shorter in group A than in group B (5.75 vs. 7.85 days, P=0.026). In the Progel group, a statistically significant reduction of hospitalisation costs compared with the control group was observed (Progel group =12,905₤, Control group =39,690₤; P<0.001). Our standardised VMT helps in reducing the length of hospital stay after VATS lobectomy because in case of IOAALs between 100 and 400 mL/min the use of ProgelTM significantly reduces postoperative air leak, time to drain removal and length of hospitalisation compared with no treatment. This shorter hospital stays results in significant cost saving benefits. Selection of patients with standardised VMT is essential to limit unnecessary intraoperative sealant treatments, thus contributing to limit the costs.

Cost-effectiveness analysis of sealant impact in management of moderate intraoperative alveolar air leaks during video-assisted thoracoscopic surgery lobectomy: a multicentre randomised controlled trial

Background

Intraoperative alveolar air leak (IOAAL) is one of most common complications after video-assisted thoracoscopic surgery (VATS) lobectomy. The study aimed to evaluate if, in moderate IOAAL, intraoperative polymeric biodegradable sealant (Progel^TM) reduced postoperative air leak (PAL) and consequently was cost-effective.

Methods

Patients with moderate IOAAL were randomised in a multicentre trial to intraoperative use of a sealant (Sealant group) or standard management of air leaks (Control group). Primary endpoint was the postoperative duration of air leakage. Secondary outcomes included: time to drainage removal, length of hospital stay, postoperative complications within 2 months, and cost analysis.

Results

Between January 2015 and January 2017, 255 VATS lobectomies were performed in four centres. Fifty-five met inclusion criteria and were randomly assigned to Sealant group [28] and Control group [27]. The mean air leakage duration was statistically different between groups (Sealant group =1.60 days, Control group =5.04 days; P<0.001). The average length of drainage was significantly (P=0.008) shorter in Sealant group (4.1 days) than in Controls (6.74 days). The mean time of hospital stay was statistically shorter in sealant group (Sealant =5.75 days, Control =7.85 days; P=0.026). Sealant group observed a statistically significant reduction of costs.

Conclusions

In moderate IOAAL after VATS lobectomy, polymeric biodegradable sealants are safe and efficient. Compared with standard treatments, sealant significantly reduces PAL, time to drain removal and length of hospital stay resulting in significant costs benefits.

Low-voltage coagulation, polyglycolic acid sheets, and fibrin glue to control air leaks in lung surgery

OBJECTIVE

We evaluated the efficacy of low-voltage coagulation (LVC) with polyglycolic acid (PGA) sheets (Neoveil, GUNZE Ltd., Japan) and fibrin glue to control intraoperative alveolar air leaks after lung surgery.

METHODS

We included 176 patients with non-small cell lung cancer who underwent thoracoscopic lobectomies. When alveolar air leak was confirmed after lung resection, we applied LVC system to the pleural defect followed by layers of PGA sheets and fibrin glue (n = 40). We then analyzed postoperative air leaks (rate of occurrence and duration time).

RESULTS

73% of patients (29/40 cases) experienced no postoperative air leaks. Although 11 patients experienced air leaks after surgery, there were no prolonged air leaks (>7 days) (resolution time, 3.5 ± 1.4 days; range, 2-6 days). Two patients required drainage for late-onset air leaks, but their conditions improved without further treatment. There were no further adverse events.

CONCLUSIONS

The use of LVC with PGA sheets and fibrin glue following pulmonary resection efficiently prevented both intraoperative air leaks and prolonged air leaks after lung surgery.

A prospective randomized trial comparing homologous and autologous fibrin sealants for the control of alveolar air leak

Background

Postoperative air leak is a common complication seen after pulmonary resection. It is a significant reason of morbidity and also leads to greater hospital cost owing to prolonged length of stay. The purpose of this study is to compare homologous sealant with autologous one to prevent air leak following pulmonary resection.

Methods

A total of 57 patients aged between 20 and 79 (mean age: 54.36) who underwent pulmonary resection other than pneumonectomy (lobar or sublobar resections) were analyzed. There were 47 males (83%) and 10 females (17%). Patients who intraoperatively had air leaks were randomized to receive homologous (Tisseel; n=28) or autologous (Vivostat; n=29) fibrin sealant. Differences among groups in terms of air leak, prolonged air leak, hospital stay, amount of air leak were analyzed.

Results

Indications for surgery were primary lung cancer in 42 patients (71.9%), secondary malignancy in 5 patients (8.8%), and benign disease in 10 patients (17.5%). Lobectomy was performed in 40 patients (70.2%), whereas 17 patients (29.8%) had wedge resection. Thirteen (46.4%) patients developed complications in patients receiving homologous sealant while 11 (38.0%) patients had complication in autologous sealant group (P=0.711). Median duration of air leak was 3 days in two groups. Time to intercostal drain removal was 3.39 and 3.38 days in homologous and autologous sealant group respectively (P=0.978). Mean hospital stay was 5.5 days in patients receiving homologous sealant whereas it was 5.0 days in patients who had autologous agent (P=0.140). There were no significant differences between groups in terms of measured maximum air leak (P=0.823) and mean air leak (P=0.186). There was no significant difference in the incidence of complications between two groups (P=0.711).

Conclusions

Autologous and heterologous fibrin sealants are safe and acts similarly in terms of air leak and hospital stay in patients who had resectional surgery.

Bronchoscopic management of prolonged air leak

Bronchopleural fistula (BPF) with prolonged air leak (PAL) is most often, though not always, a sequela of lung resection. When this complication occurs post-operatively, it is associated with substantial morbidity and mortality. Surgical closure of the defect is considered the definitive approach to controlling the source of the leak, but many patients with this condition are suboptimal operative candidates. Therefore there has been active interest for decades in the development of effective endoscopic management options. Successful use of numerous bronchoscopic techniques has been reported in the literature largely in the form of retrospective series and, at best, small prospective trials. In general, these modalities fall into one of two broad categories: implantation of a device or administration of a chemical agent. Closure rates are high in published reports, but the studies are limited by their small size and multiple sources of bias. The endoscopic procedure currently undergoing the most systematic investigation is the placement of endobronchial valves. The aim of this review is to present a concise discussion on the subject of PAL and summarize the described bronchoscopic approaches to its management.

Management of Prolonged Pulmonary Air Leaks With Endobronchial Valve Placement

Background:

Prolonged pulmonary air leaks (PALs) are associated with increased morbidity and extended hospital stay. We sought to investigate the role of bronchoscopic placement of 1-way valves in treating this condition.

Methods:

We queried a prospectively maintained database of patients with PAL lasting more than 7 days at a tertiary medical center. Main outcome measures included duration of chest tube placement and hospital stay before and after valve deployment.

Results:

Sixteen patients were eligible to be enrolled from September 2012 through December 2014. One patient refused to give consent, and in 4 patients, the source of air leak could not be identified with bronchoscopic balloon occlusion. Eleven patients (9 men; mean age, 65 ± 15 years) underwent bronchoscopic valve deployment. Eight patients had postoperative PAL and 3 had a secondary spontaneous pneumothorax. The mean duration of air leak before valve deployment was 16 ± 12 days, and the mean number of implanted valves was 1.9 (median, 2). Mean duration of hospital stay before and after valve deployment was 18 and 9 days, respectively (P = .03). Patients who had more than a 50% decrease in air leak on digital monitoring had the thoracostomy tube removed within 3–6 days. There were no procedural complications related to deployment or removal of the valves.

Conclusions:

Bronchoscopic placement of 1-way valves is a safe procedure that could help manage patients with prolonged PAL. A prospective randomized trial with cost-efficiency analysis is necessary to better define the role of this bronchoscopic intervention and demonstrate its effect on air leak duration.

Air leak: An unusual manifestation of organizing pneumonia secondary to bleomycin

Organizing pneumonia (OP) is a less common interstitial lung disease with varying clinical picture. The development of pulmonary air leak in a case of OP is an extremely rare complication. Here, we report the case of a 46-year-old female with carcinoma ovary, postchemotherapy who developed respiratory distress with pneumomediastinum, and subcutaneous emphysema. Lung biopsy showed evidence of OP. This turned out to be a rare case of OP, secondary to bleomycin chemotherapy, presenting with pulmonary air leak.

Suction or Nonsuction: How to Manage a Chest Tube After Pulmonary Resection

Despite several randomized trials and meta-analyses, the dilemma as to whether to apply suction after subtotal pulmonary resection has not been solved. The combination of a poorly understood pathophysiology of the air leak phenomenon and the inadequate quality of the published randomized trials is actually preventing thoracic surgeons from abandoning an empirical management of chest drains. Even digital systems do not seem to have made the difference so far. Based on the evidence of the literature, the authors propose a new air leak predictor score (ALPS) as a contributing step toward appropriateness in using intraoperative sealants, opting for an external suction and managing and chest tubes.

Chest Tubes: Generalities

Insertion, management, and withdrawal of chest tubes is part of the routine activity of thoracic surgeons. The selection of the chest tube and the strategy for each of these steps is usually built on knowledge, practice, experience, and judgment. The indication to insert a chest tube into the pleural cavity is the presence of air or fluid within it. Various types and sizes of chest tubes are now commercially available.

When size matters: changing opinion in the management of pleural space-the rise of small-bore pleural catheters

Tube thoracostomy is usually the first step to treat several thoracic/pleural conditions such as pneumothorax, pleural effusions, haemothorax, haemo-pneumothorax and empyema. Today, a wide range of drains is available, ranging from small to large bore ones. Indications for an appropriate selection remains yet matter of debate, especially regarding the use of small bore catheters. Through this paper, we aimed to retrace the improvements of drains through the years and to review the current clinical indications for chest drain placement in pleural/thoracic diseases, comparing the effectiveness of small-bore drains vs. large-bore ones.

Albumin-glutaraldehyde glue for repair of superficial lung defect: an in vitro experiment

Background

Albumin-glutaraldehyde glue gained a widespread acceptance in repair of superficial lung defects associated with alveolar air leaks (AAL). As its sealing efficacy has not yet been thoroughly corroborated by clinical studies, we sought to assess the properties of commercially available albumin-glutaraldehyde glue (BioGlue™) in an in vitro lung model.

Methods

The lower lobe of freshly excised swine lung (n = 10) was intubated and ventilated. A focal superficial parenchymal defect (40 × 25 mm) was created on the inflated lung. AAL was assessed with increasing inspired tidal volume (TVi). After glue application, AAL was assessed until burst failure occurred. To evaluate glue elasticity, the length of defect was recorded in the inflated lung.

Results

Superficial parenchymal defects resulted in AAL increasing with ascending TVi. Multiple linear regression analysis revealed strong correlation between AAL and maximal inspiratory pressure. There was one application error. At TVi = 400, 500, 600, 700, 800 and 900 ml, BioGlue™ achieved complete sealing in nine, six, five, four two and one specimens, respectively. Mean burst pressure was 38.0 ± 4.2 cmH₂O. All sealant failures were cohesive. BioGlue™ allowed an expansion of covered lung defects of 1.5 ± 1.7 mm.

Conclusions

Our in vitro tests demonstrated a high sealing efficacy of BioGlue™ for repair of superficial lung defects. Due to the rigid nature, caution should be taken to use this kind of sealant in trapped lungs.

Air leak after lung resection: pathophysiology and patients' implications

Protocols for the management of air leaks are critical aspects in the postoperative course of patients following lung resections. Many investigations in the last decade are focusing on the chest tube modalities or preventative measures, however, little is known about the pathophysiology of air leak and the patient perception of this common complication. This review concentrates on understanding the reasons why a pulmonary parenchyma may start to leak or an air leak may be longer than others. Experimental works support the notion that lung overdistension may favor air leak. These studies may represent the basis of future investigations. Furthermore, the standardization of nomenclature in the field of pleural space management and the creation of novel air leak scoring systems have contributed to improve the knowledge among thoracic surgeons and facilitate the organization of trials on this matter. We tried to summarize available evidences about the patient perception of a prolonged air leak and about what would be useful for them in order to prevent worsening of their quality of life. Future investigations are warranted to better understand the pathophysiologic mechanisms responsible of prolonged air leak in order to define tailored treatments and protocols. Improving the care at home with web-based telemonitoring or real time connected chest drainage may in a future improve the quality of life of the patients experience this complication and also enhance hospital finances.

A rare cause of respiratory distress after transthoracic oesophagectomy

Transthoracic oesophagectomy is a standard surgical procedure for oesophageal cancer. Because of thoracotomy and lung handling, perioperative pulmonary complications make such procedures challenging. The issues related to respiratory complications may be predicted and managed accordingly. However, we report two cases of respiratory compromise caused due to a peculiar iatrogenic component.

Recurrent air leak soon after pulmonary lobectomy: an analysis based on an electronic airflow evaluation†

OBJECTIVES

The objective of this analysis was to evaluate the incidence and risk factors of recurrent air leak (RAL) occurring soon after pulmonary lobectomy based on electronic airflow measurements.

METHODS

A prospective observational analysis of 129 consecutive patients managed with a single chest tube connected with an electronic chest drainage system. The incidence and timing of RAL among patients who had an air leak sealed within the first 24 postoperative hours was recorded. Stepwise logistic regression and bootstrap analyses were used to test the association of several baseline and surgical variables with RAL.

RESULTS

A total of 95 patients (68%) had their air leak stopped within 24 h after the operation. Twelve patients had RAL (13%) after the first stop. All RALs occurred within the first 24 h from operation. Logistic regression showed that the presence of moderate-to-severe chronic obstructive pulmonary disease [COPD; forced expiratory volume in 1 s (FEV1) <80% and FEV1/forced vital capacity ratio <0.7] was an independent risk factor associated with RAL (P = 0.02, bootstrap frequency 83%). Seven of 27 (26%) patients with COPD had RAL, a proportion significantly higher than in patients without COPD (5 of 68, 7.3%, P = 0.03).

CONCLUSIONS

A large proportion of patients with COPD developed RAL. In this high-risk group, we advise against chest tube removal in the first 24 h after operation, even in the case of absence or cessation of air leak.

Postlobectomy Early Complications

Immediate postoperative complications are common after lobectomy. The most effective management of postoperative crises is prevention, which starts with preoperative preparation and patient screening. There are many factors that can be controlled and improved by the patient. Equally important is patient selection, which is influenced by pulmonary function tests, cardiopulmonary reserve, and preexisting comorbidities. After the operation, the care team can also greatly improve outcomes with aggressive cardiopulmonary therapies, ambulation, vigilant monitoring, and frequent assessments of the patient. Prevention strategies can minimize risks; however, when they occur, a proactive approach may minimize the long-term sequelae.

Suction on chest drains following lung resection: evidence and practice are not aligned

OBJECTIVES

A best evidence topic in Interactive CardioVascular and Thoracic Surgery (2006) looked at application of suction to chest drains following pulmonary lobectomy. After screening 391 papers, the authors analysed six studies (five randomized controlled trials [RCTs]) and found no evidence in favour of postoperative suction in terms of air leak duration, time to chest drain removal or length of stay. Indeed, suction was found to be detrimental in four studies. We sought to determine whether clinical practice is consistent with published evidence by surveying thoracic units nationally and performing a meta-analysis of current best evidence.

METHODS

We systematically searched MEDLINE, EMBASE and CENTRAL for RCTs, comparing outcomes with and without application of suction to chest drains after lung surgery. A meta-analysis was performed using RevMan(©) software. A questionnaire concerning chest drain management and suction use was emailed to a clinical representative in every thoracic unit.

RESULTS

Eight RCTs, published 2001-13, with 31-500 participants, were suitable for meta-analysis. Suction prolonged length of stay (weighted mean difference [WMD] 1.74 days; 95% confidence interval [CI] 1.17-2.30), chest tube duration (WMD 1.77 days; 95% CI 1.47-2.07) and air leak duration (WMD 1.47 days; 95% CI 1.45-2.03). There was no difference in occurrence of prolonged air leak. Suction was associated with fewer instances of postoperative pneumothorax. Twenty-five of 39 thoracic units responded to the national survey. Suction is routinely used by all surgeons in 11 units, not by any surgeon in 5 and by some surgeons in 9. Of the 91 surgeons represented, 62 (68%) routinely used suction. Electronic drains are used in 15 units, 10 of which use them routinely.

CONCLUSIONS

Application of suction to chest drains following non-pneumonectomy lung resection is common practice. Suction has an effect in hastening the removal of air and fluid in clinical experience but a policy of suction after lung resection has not been shown to offer improved clinical outcomes. Clinical practice is not aligned with Level 1a evidence.

Endobronchial occlusion with one-way endobronchial valves: a novel technique for persistent air leaks in children

PURPOSE

In children, persistent air leaks can result from pulmonary infection or barotrauma. Management strategies include surgery, prolonged pleural drainage, ventilator manipulation, and extracorporeal membrane oxygenation (ECMO). We report the use of endobronchial valve placement as an effective minimally invasive intervention for persistent air leaks in children.

METHODS

Children with refractory prolonged air leaks were evaluated by a multidisciplinary team (pediatric surgery, interventional pulmonology, pediatric intensive care, and thoracic surgery) for endobronchial valve placement. Flexible bronchoscopy was performed, and air leak location was isolated with balloon occlusion. Retrievable one-way endobronchial valves were placed.

RESULTS

Four children (16 months to 16 years) had prolonged air leaks following necrotizing pneumonia (2), lobectomy (1), and pneumatocele (1). Patients had 1-4 valves placed. Average time to air leak resolution was 12 days (range 0-39). Average duration to chest tube removal was 25 days (range 7-39). All four children had complete resolution of air leaks. All were discharged from the hospital. None required additional surgical interventions.

CONCLUSION

Endobronchial valve placement for prolonged air leaks owing to a variety of etiologies was effective in these children for treating air leaks, and their use may result in resolution of fistulae and avoidance of the morbidity of pulmonary surgery.

Clinical usefulness of free subcutaneous fat pad for reduction of intraoperative air leakage during thoracoscopic pulmonary resection in lung cancer cases

INTRODUCTION

Intraoperative alveolar air leaks remain a significant problem in thoracoscopic surgery (TS) cases. We examined the usefulness of covering damaged lung tissue with a subcutaneous fat pad for preventing postoperative air leakage in patients with non-small cell lung cancer (NSCLC).

METHODS

Patients with NSCLC underwent a thoracoscopic lobectomy or segmentectomy. When alveolar air leakage from the superficial pulmonary parenchyma was found, fibrin glue in combination with an absorbable mesh sheet was applied (S group; n = 100). When leakage originated from deep within the pulmonary parenchyma, a subcutaneous fat pad about 2 × 2 cm in size was harvested from the utility incision and placed on the damaged lung tissue with fibrin glue and sutures (F group; n = 66). Patient characteristics, air leak duration, and chest-tube removal time were analyzed.

RESULTS

The homogeneity of each group was consistent, with no statistical differences for age, respiratory function, surgical procedures, pathologic stage, and histological type. The air leak duration was significantly shorter (p = 0.015), and the chest tube was removed significantly earlier (p = 0.002) in patients in the F group.

CONCLUSION

Use of a free subcutaneous fat pad during pulmonary resection for TS patients with NSCLC reduced the duration of air leakage and chest tube drainage. The present method is easy, safe, and effective for repairing an air leak from remaining lung tissues in such cases.