Pneumothorax ex vacuo

Re-expansion Pulmonary Edema (REPE) Following Thoracentesis: Is Large-Volume Thoracentesis Associated with Increased Incidence of REPE?

PURPOSE

To determine the safety and efficacy associated with drainage volumes greater than 1,500 mL in a single, unilateral thoracentesis without pleural manometry measurements.

MATERIALS AND METHODS

This retrospective, single-institution study included 872 patients (18 years and older) who underwent ultrasound-guided thoracentesis. Patient and procedures data were collected including demographics, number of and laterality of thoracenteses, volume and consistency of fluid removed, and whether clinical or radiologic evidence of re-expansion pulmonary edema (REPE) developed within 24 h of thoracentesis. Fisher's exact test was used to test the significance of the relationship between volume of fluid removed and evidence of REPE.

RESULTS

A total of 1376 thoracenteses were performed among the patients included in the study. The mean volume of fluid removed among all procedures was 901.1 mL (SD = 641.7 mL), with 194 (14.1%) procedures involving the removal of ≥ 1,500 mL of fluid. In total, six (0.7%) patients developed signs of REPE following thoracentesis, five of which were a first-time thoracentesis. No statistically significant difference in incidence of REPE was observed between those with ≥ 1,500 mL of fluid removed compared to those with < 1,500 mL of fluid removed (p-value = 0.599).

CONCLUSIONS

Large-volume thoracentesis may safely improve patients' symptoms while preventing the need for repeat procedures.

Pressure-Dependent Pneumothorax and Air Leak: Physiology and Clinical Implications

Pressure-dependent pneumothorax is a common clinical event, often occurring after pleural drainage in patients with visceral pleural restriction, partial lung resection, or lobar atelectasis from bronchoscopic lung volume reduction or an endobronchial obstruction. This type of pneumothorax and air leak is clinically inconsequential. Failure to appreciate the benign nature of such air leaks may result in unnecessary pleural procedures or prolonged hospital stay. This review suggests that identification of pressure-dependent pneumothorax is clinically important because the air leak that results is not related to a lung injury that requires repair but rather to a physiological consequence of a pressure gradient. A pressure-dependent pneumothorax occurs during pleural drainage in patients with lung-thoracic cavity shape/size mismatch. It is caused by an air leak related to a pressure gradient between the subpleural lung parenchyma and the pleural space. Pressure-dependent pneumothorax and air leak do not need any further pleural interventions.

Pneumothorax ex vacuo: Three cases of an uncommon entity

Pneumothorax is a frequently encountered entity in pulmonary practice and can be primary or secondary. Traumatic and iatrogenic causes also account for a minority of cases presenting to the chest physician. The most common therapeutic intervention done is a tube thoracostomy in all but the mildest of cases. Pneumothorax ex vacuo is a distinctly uncommon entity that differs considerably from the rest of the pneumothorax cases in its pathogenesis, clinical manifestations, radiological findings, and management. Pneumothorax in this entity results from the sucking in of air into the pleural space caused by an exaggerated negative intrapleural pressure, which is most frequently secondary to acute lobar collapse. Symptoms attributable to pneumothorax per se are distinctly mild and the vital aspect of treatment is to relieve the bronchial obstruction. Tube thoracostomy fails to relieve the pneumothorax in such cases and should be avoided. We share three cases of pneumothorax ex vacuo encountered in our institution and alert clinicians of the presentation, radiology, and management of this uncommon condition.

Impact of pneumothorax-like pulmonary collapse caused by rapid bronchial obstruction: A case report of pneumothorax ex vacuo

We report two cases of pulmonary collapse that simulated pneumothorax on computed tomographic images and were caused by rapid complete bronchial obstruction. One patient was a 77-year-old woman with sudden dyspnea, and the other was an 83-year-old woman with sudden dyspnea who was infected with influenza A virus. Chest computed tomography revealed lobular complete atelectasis with an almost complete expansion of the other lobes of the right lung. Some air space in the right pleural cavity was also observed. Both cases were diagnosed as "pneumothorax" by primary doctors. We noted the disappearance of air density in the lumen of the right bronchus in both cases. We performed bronchoscopy before thoracic drainage and removed the obstruction. Immediately, the obstructed pulmonary lobes expanded, and the air space in the pleural cavity disappeared without thoracic drainage. In the literature, this pneumothorax-like pulmonary collapse is called as "pneumothorax ex vacuo."

Long-Term Follow-Up of Intralobar Bullae After Endobronchial Valve Treatment for Emphysema

Endoscopic lung volume reduction using unidirectional endobronchial valves is a new technique in the treatment of patients with severe emphysema. However, the movements of the thoracic structures after endobronchial valves insertion are still unpredictable We report the unusual outcome of six patients after valves insertion in the left upper lobe. They all developed a complete atelectasis of the target lobe, a pneumothorax and sequential genuine bullae in the treated left lung of unknown etiology. The chest CT scan prior to the valves insertion was unremarkable. Three patients developed an air–liquid level in the bullae the day before a bacterial infection of their left lower lobe. The three other patients had an uneventful spontaneous resolution of their bullae at long-term follow-up. Therefore, a conservative attitude should be followed in this particular setting.

Pneumothorax as a rare presentation of bronchial schwannoma

Tracheobronchial schwannomas are rare diseases. Common signs and symptoms of this tumor include cough, wheezing, and dyspnea. In contrast, pneumothorax is an exceptional presentation. This study reports the first case of bronchial schwannoma presenting with pneumothorax. A 79-year-old woman was diagnosed with pneumothorax by chest radiography. Chest computed tomography unexpectedly revealed a tumor occluding the right main bronchus. Following the pathological diagnosis of bronchial schwannoma, the patient underwent thoracoscopic tumor enucleation. The airway lumens are consequently secured postoperatively. We reviewed the literature and discussed the mechanisms and treatment options for bronchial benign tumor-associated pneumothorax. Pneumothorax should be aware of a rare presentation of non-malignant tracheobronchial tumors.

Expert Statement: Pneumothorax Associated with One-Way Valve Therapy for Emphysema: 2020 Update

For selected patients with advanced emphysema, bronchoscopic lung volume reduction with one-way valves can lead to clinically relevant improvements of airflow obstruction, hyperinflation, exercise capacity, and quality of life. The most common complication of this procedure is pneumothorax with a prevalence of up to ±34% of the treated patients. Patients who develop a pneumothorax also experience meaningful clinical benefits once the pneumothorax is resolved. Timely resolution of a post-valve treatment pneumothorax requires skilled and adequate pneumothorax management. This expert panel statement is an updated recommendation of the 2014 statement developed to help guide pneumothorax management after valve placement. Additionally, mechanisms for pneumothorax development, risk assessment, prevention of pneumothorax, and outcomes after pneumothorax are addressed. This recommendation is based on a combination of the current scientific literature and expert opinion, which was obtained through a modified Delphi method.

Endobronchial valve therapy for severe emphysema: an overview of valve-related complications and its management

INTRODUCTION

Bronchoscopic lung volume reduction treatment with one-way valves is an effective guideline treatment option for patients with severe emphysema. However, important challenges and adverse reactions may occur after treatment.

AREAS COVERED

This review summarizes the complications after endobronchial and intrabronchial valve treatment that have been described by the currently published randomized controlled trials and other relevant papers regarding the complications and its management. In case there was no relevant literature regarding these subjects, recommendations are based on expert opinion. Complications include pneumothorax, post-obstruction pneumonia and hemoptysis. Also, the treatment may not be effective due to the presence of collateral ventilation or misplaced valves. Furthermore, an initial beneficial effect may vanish due to granulation tissue formation, valve dysfunction or valve migration. Careful follow-up after treatment with valves is important. Evaluation with a CT-scan and/or bronchoscopy is needed if there is no improvement after treatment, loss of benefit, or occurrence of important adverse events during follow-up.

EXPERT OPINION

Treating severe emphysema patients with one-way valves requires continuous dedication and expertise, especially to achieve an optimal outcome and elegantly deal with the various complications after treatment.

Demystifying the persistent pneumothorax: role of imaging

Evaluation for pneumothorax is an important indication for obtaining chest radiographs in patients who have had trauma, recent cardiothoracic surgery or are on ventilator support. By definition, a persistent pneumothorax constitutes ongoing bubbling of air from an in situ chest drain, 48 h after its insertion. Persistent pneumothorax remains a diagnostic dilemma and identification of potentially treatable aetiologies is important. These may be chest tube related (kinks or malposition), lung parenchymal disease, bronchopleural fistula, or rarely, oesophageal-pleural fistula. Although radiographs remain the mainstay for diagnosis and follow up of pneumothorax, computed tomography (CT) is increasingly being used for problem solving. Aetiology of persistent air leak determines the optimal treatment. For some, a simple repositioning of the chest tube/drain may suffice; others may require surgery. In this pictorial review, we will briefly describe the physiology of pneumothorax, discuss imaging features of identifiable causes for persistent pneumothorax and provide a brief overview of treatment options. Specific aetiology of a persistent air leak may often not be immediately discernible, and will need to be carefully sought. Accurate interpretation of imaging studies can expedite diagnosis and facilitate prompt treatment.

Key points

• Persistent pneumothorax is defined as a leak persisting for more than 2 days.

• Radiographs can identify chest-tube-related causes of pneumothorax.

• CT is the most useful test to identify other causes.

• Penetrating thoracic injury can cause fistulous communication resulting in a persistent pneumothorax.

• Discontinuity of visceral pleura identified by CT may indicate a bronchopleural fistula.

Endobronchial Primitive Neuroectodermal Tumor With Pneumothorax Ex Vacuo

We experienced a rare case of an endobronchial primitive neuroectodermal tumor of the left main bronchus. Initially we suspected pneumothorax caused by a collapsed left upper lobe and an air-entrapped lower lobe. After tube thoracostomy, the pneumothorax persisted without air leakage. A tumor was detected at the left main bronchus on computed tomography and bronchoscopy, and diagnosed pathologically as small cell lung cancer. Under the presumed diagnosis of limited-stage small cell lung cancer, we performed a left pneumonectomy. The tumor was eventually identified pathologically as a primitive neuroectodermal tumor. Although adjuvant chemoradiotherapy was not performed, no recurrence was observed.

An update on the efficacy of endobronchial valve therapy in the management of hyperinflation in patients with chronic obstructive pulmonary disease

Lung volume reduction surgery has been shown to be effective in patients with heterogeneous emphysema, but is also associated with a relatively high perioperative morbidity and mortality. Accordingly, several novel and potentially less invasive methods for bronchoscopic lung volume reduction have been developed. Endobronchial valve (EBV) therapy is one such therapeutic approach in patients with advanced emphysema. It has been the most widely studied technique over the past years and represents an effective treatment option for patients with severe heterogeneous upper- or lower-lobe-predominant emphysema. The choice of EBV therapy largely depends on the distribution of emphysema and the presence or absence of interlobar collateral ventilation. Adequate patient selection and technical success of valve implantation with the intention of lobar exclusion are predictive factors for positive outcomes. This review attempts to highlight the milestones in the development of bronchoscopic lung volume reduction with one-way valve implantation over the past few years.

Experimental lung collapse following deployment of a self-expandable bronchial occluder in a rabbit model

OBJECTIVES

Closure of a bronchopleural fistula is required to prevent fatal empyema or aspiration pneumonia. The purpose of this study was to determine the feasibility and efficacy of bronchial occlusion with a self-expandable occluder to induce experimental lung collapse in a rabbit model.

METHODS

10 bronchial occluders (wine glass appearance; 8 mm in diameter and 15 mm in length) were implanted in the native left main bronchi of 10 rabbits via an endotracheal route. We analysed the following: (1) diameters and morphological changes of the bronchial occluders during follow-up; (2) percentage volume of the collapsed lung during follow-up; and (3) complications and gross pathology. 1-day and 2-week follow-up CT scans were routinely obtained. Rabbits were sacrificed 4 weeks after the experiment.

RESULTS

In all 10 rabbits, the bronchial occluders were successfully implanted and were completely expanded within 2 weeks. Complete collapse of the left lung occurred in three rabbits on day 1 and in an additional two rabbits 2 weeks following implantation. Two other rabbits maintained the percentage volume of the collapsed lung between 51% and 99% during follow-up; the other three rabbits had <50% during follow-up. Pneumothoraces occurred in nine rabbits, but completely resolved at the 2-week follow-up. Right lung herniation across the midline progressed 2 weeks after occluder implantation.

CONCLUSION

Placement of self-expandable occluders in a rabbit bronchus model was feasible and showed a potential to induce artificial lung collapse. While pneumothoraces were common, they resolved during follow-up.

Bronchoscopic Lung Volume Reduction for End-Stage Emphysema

OBJECTIVES

To report the first multicenter experience on the treatment of end-stage emphysema using an endobronchial valve (EBV) [Emphasys EBV; Emphasys Medical; Redwood City, CA].

DESIGN

Retrospective analysis from prospective multicenter registry.

PATIENTS AND INTERVENTIONS

This is a study of the use of EBVs in the treatment of end-stage emphysema at nine centers in seven countries. Ninety-eight patients with mean FEV(1) of 0.9 +/- 0.3 L (30.1 +/- 10.7% of predicted) [+/- SD] and residual volume (RV) of 5.1 +/- 1.3 L (244.3 +/- 0.3% of predicted) were treated over a period of 20 months. Spirometry, plethysmography, and diffusing capacity of the lung for carbon monoxide (Dlco) and exercise tolerance testing were performed at 30 days and 90 days after the procedure.

RESULTS

RV decreased by 4.9 +/- 17.4% (p = 0.025), FEV(1) increased by 10.7 +/- 26.2% (p = 0.007), FVC increased by 9.0 +/- 23.9% (p = 0.024), and 6-min walk distance increased by 23.0 + 55.3% (p = 0.001). There was a trend toward improvement in Dlco, but this did not reach statistical significance (17.2 +/- 52.0%, p = 0.063). Patients treated unilaterally showed a trend toward greater improvement than those treated bilaterally. A similar trend toward improvement was observed in patients who had one entire lobe treated compared to those with just one or two bronchopulmonary segments treated. Eight patients (8.2%) had serious complications in the first 90 days, including one death (1.0%).

CONCLUSION

This multicenter analysis confirms that improvement in pulmonary function and exercise tolerance can be achieved in emphysematous patients using EBVs. Future efforts should be directed to determining how to select those patients who would benefit most from this procedure and the best endobronchial treatment strategy.

Management of patients with "ex vacuo" pneumothorax after thoracentesis

RATIONALE AND OBJECTIVES

To determine clinical outcome in patients who developed "ex vacuo" pneumothorax following thoracentesis and to assess the benefit of chest tube placement for this complication.

MATERIALS AND METHODS

We retrospectively reviewed records of 282 patients who underwent 437 thoracenteses at a single institution during a 6-year period. We identified 34 patients (12.1%) who developed a pneumothorax following 39 thoracenteses (8.8%) and then identified a subset of patients with pneumothorax "ex vacuo" defined as a moderate to large hydropneumothorax or small pneumothorax persisting for more than 3 days. Patient charts were reviewed to document the treatment strategy employed and subsequent clinical outcome, which included length of hospital stay, resolution of pneumothorax, reaccumulation of pleural effusion, and overall survival.

RESULTS

Ten patients developed "ex vacuo" pneumothroax following thoracentesis. None complained of significant worsening of symptoms following thoracentesis. Seven patients were treated by observation alone and 3 patients underwent tube thorocostomy. A decrease in size of the pneumothorax was observed in only 3 patients, none of whom had a chest tube placed. Effusion completely reaccumulated in 7 patients. All 10 patients died during the follow-up period; the mean survival was 157 days (range: 13-402 days). Survival among patients treated by observation was 191.4 days versus 71.7 days for patients receiving chest tubes.

CONCLUSION

Life expectancy for most patients who develop "ex vacuo" pneumothorax following therapeutic thoracentesis is short (<6 months). Chest tube placement is not necessary in asymptomatic patients and is unlikely to provide clinical benefit.

Management of pneumothorax and barotrauma: current concepts

Pneumothorax can be spontaneous, traumatic or iatrogenic. Pneumothorax ex vacuo, sports-related pneumothorax and barotrauma unrelated to mechanical ventilation are interesting and newer entities. Management consists of getting rid of the air and prevention of recurrence of pneumothorax.

Pneumorachis and pneumomediastinum caused by repeated Müller's maneuvers: complications of marijuana smoking

Pneumomediastinum may occur during marijuana inhalation but only rarely has pneumorachis (epidural pneumatosis or aerorachia) been reported. The usual mechanisms that produce pneumomediastinum include severe acute asthma, toxic-induced bronchial hyperreactivity, and barotrauma caused by Valsalva's maneuver (expiration through resistance). We report a case in which barotrauma resulted from repeated deep inspiration through a device with airflow resistance equivalent to Müller's maneuver. Inspiration occurred through a homemade apparatus resembling a narrow outlet bong with 2 piled compartments. Pneumomediastinum combined with subcutaneous emphysema and pneumorachis occurred, without identified pneumothorax. There were no neurologic complications. Because of the absence of bronchospasm, expiration either through the apparatus or actively against a closed glottis, or apnea, this phenomenon is likely a result of repeated Müller's maneuvers. Successive inhalation through resistance could have resulted in extreme negative intrathoracic pressure, which would have caused a transmural pressure gradient inducing barotrauma and release of extrarespiratory air. High-concentration oxygen therapy to achieve nitrogen washout was used.