Pneumothorax

Does pre-injury anticoagulation make chest tubes any less safe? A nationwide retrospective analysis

BACKGROUND

Oral anticoagulation is becoming more common with the aging population, which raises concern for the risk of invasive procedures that can cause bleeding, such as chest tube placement (thoracostomy). With the increase in CT imaging, more pneumothoraces and hemothoraces are being identified. The relative risk of thoracostomy in the presence of anticoagulation is not well-established. The objective of this study was to determine whether pre-injury anticoagulation affects the relative risk of tube thoracostomy following significant chest trauma.

METHODS

This retrospective cohort study used data from the 2019 American College of Surgeons-Trauma Quality Program (ACS-TQP) database using R version 4.2.2. Data from the database was filtered based on inclusion and exclusion criteria. Outcomes were then assessed with the population of interest. Demographics, vitals, comorbidities, and injury parameters were also collected for each patient. This study included all adult patients (≥18 years) presenting with traumatic hemothorax, pneumothorax, or hemopneumothorax. Patients with missing data in demographics, vitals, comorbidities, injury parameters, or outcomes, as well as those with no signs of life upon arrival, were excluded from the study. Patients were stratified into groups based on whether they had pre-injury anticoagulation and whether they had a chest tube placed in the hospital. The primary outcome was mortality, and the secondary outcome was hospital length of stay (LOS). Logistic and standard regressions were used by a statistician to control for age, sex, and Injury Severity Score (ISS).

RESULTS

Our study population included 72,385 patients (4250 with pre-injury anticoagulation and 68,135 without pre-injury anticoagulation). Pre-injury anticoagulation and thoracostomy were each independently associated with increased mortality and LOS. However, there was a non-significant interaction term between pre-injury anticoagulation and thoracostomy for both outcomes, indicating that their combined effects on mortality and LOS did not differ significantly from the sum of their individual effects.

CONCLUSION

This study suggests that both pre-injury anticoagulation and thoracostomy are risk factors for mortality and increased LOS in adult patients presenting with hemothorax, pneumothorax, or hemopneumothorax, but they do not interact with each other. We recommend further study of this phenomenon to potentially improve clinical guidelines.

LEVEL OF EVIDENCE

Therapeutic, Level III.

Pulmonary tuberculoma-induced cyst formation leading to repeated pneumothorax: a case report

Most cases of secondary spontaneous pneumothorax in patients with active pulmonary tuberculosis are caused by rupturing of the visceral pleura caused by Mycobacterium tuberculosis. The check-valve airway mechanism in the lungs is generally involved in the formation of pulmonary cysts, which often cause spontaneous pneumothorax. Herein, we describe a rare case of repeated spontaneous pneumothorax suspected to have been caused by pulmonary cyst formation as a result of a tuberculoma. The patient was a man with a family history of pulmonary tuberculosis. Pulmonary cysts were gradually enlarged on the peripheral side of a lung mass in the upper lobe of the patient's right lung, who experienced two spontaneous pneumothoraxes in the area. Exploratory surgery was performed to diagnose the lung mass and treat the pneumothorax, resulting in a final diagnosis of pulmonary tuberculoma. A check-valve mechanism caused by the pulmonary tuberculoma was suspected based on the patient's clinical course.

Spontaneous Pneumothorax, Pneumomediastinum, and Pneumopericardium in an HIV Patient With Tuberculosis: A Rare Trio

A trio of spontaneous pneumomediastinum, pneumopericardium, and pneumothorax is a highly unusual presentation. The majority of reported cases are due to trauma, while the remaining cases are iatrogenic. Among infections, this trio has so far been reported in COVID-19 pneumonia and pneumocystis pneumonia in HIV-positive patients. There are case reports on pneumothorax and pneumomediastinum in tuberculosis, but the trio is not reported. Here, we present a case of a recently diagnosed HIV-positive patient with complaints of cough and shortness of breath whose initial workup was negative for Mycobacterium. The patient was, however, started on antitubercular drugs based on clinical radiological evidence. He developed spontaneous pneumothorax, pneumomediastinum, and pneumopericardium, and repeat bronchoalveolar lavage (BAL) came positive for Mycobacterium. The patient, however, could not be revived and succumbed to obstructive and septic shock.

Comparison of Observation Alone Versus Interventional Procedures in Hemodynamically Stable Patients With Pneumothorax: A Systematic Review and Meta-Analysis

Several studies indicate that observation alone is sufficient for the management of stable pneumothorax. To compare clinical efficacy, tolerability, and safety outcomes for treating hemodynamically stable adult patients with pneumothorax, the present review compared observation alone versus interventional procedures. We searched PubMed and Google Scholar from inception until June 24, 2020, for randomized controlled trials (RCTs) comparing observational therapy with conventional therapy for the treatment of adult pneumothorax. The pediatric age group and patients with tension pneumothorax were not included. Four hundred and forty-six patients were enrolled in three RCTs. The failure rate (relative risk (RR) 4.30; 95% CI = 0.23-81.82, p = 0.33) and mortality (RR 1.01; 95% CI = 0.31-3.33, p = 0.98) of observation were comparable to those of the chest tube. Chest tube and observation both carried comparable risks of complications, including tension pneumothorax and empyema (RR 3.15; 95% CI = 0.67-1) and (RR 1.55; 95% CI = 0.21-11.56, p = 0.67), respectively. Between chest tubes and observation, there was no statistically significant difference in the duration of hospital stay. We conclude that observation is as safe and effective at treating adult patients with stable pneumothorax as a chest tube.

Prolonged Non-Steroidal Anti-Inflammatory Drug Exposure After Pleurodesis Increases Pneumothorax Recurrence: A Retrospective Cohort Study

INTRODUCTION

The use of non-steroidal anti-inflammatory drugs (NSAID) in patients undergoing pleurodesis remains controversial. Although many surgeons are comfortable prescribing NSAIDs post-operatively, some oppose this practice due to concerns of suppressing the inflammatory response and quality of pleurodesis. Only a small body of inconsistent publications exists with respect to guiding therapy in this common clinical scenario.

METHODS

A retrospective cohort study was undertaken assessing effect of NSAID exposure on pleurodesis outcomes. An institutional thoracic surgery database was reviewed yielding 147 patients who underwent pleurodesis for pneumothorax between 2010 and 2018. Medical records and imaging were reviewed for patient characteristics, NSAID exposure, recurrent pneumothorax and other adverse events.

RESULTS

There was no overall difference between rates of recurrence and procedural failure of pleurodesis (Relative Risk [RR] 1.67 [95% CI 0.74-3.77]). However, NSAID exposure of >48 hours was associated with increased risk of recurrent pneumothorax (RR 2.16 [95% CI 1.05-4.45]). There was no increased rate of other adverse events related to NSAID usage.

CONCLUSIONS

NSAID exposure does not increase failure rates or other adverse events following pleurodesis for pneumothorax. However, prolonged NSAID exposure post-pleurodesis may increase procedural failure rates. Further large volume randomised control trials are required.

Successful Needle Aspiration of a Traumatic Pneumothorax: A Case Report and Literature Review

Traumatic pneumothorax (PTX) occurs in up to 50% of patients with severe polytrauma and chest injuries. Patients with a traumatic PTX with clinical signs of tension physiology and hemodynamic instability are typically treated with an urgent decompressive thoracostomy, tube thoracostomy, or needle decompression. There is recent evidence that non-breathless patients with a hemodynamically stable traumatic PTX can be managed conservatively through observation or a percutaneous pigtail catheter. We present here a 52-year-old woman who presented to the emergency department with a 55 mm traumatic PTX. Following aspiration of 1500 mL of air, a clinical improvement was immediately observed, allowing the patient to be discharged shortly thereafter. In hemodynamically stable patients with a post-traumatic PTX, without specific risk factors or oxygen desaturation, observation or simple needle aspiration can be a reasonable approach. Although the recent medical literature supports conservative management of small traumatic PTXs, guidelines are lacking for hemodynamically stable patients with a significantly large PTX. This case report documents our successful experience with needle aspiration in such a setting of large traumatic PTX. We aimed in this article to review the available literature on needle aspiration and conservative treatment of traumatic pneumothorax. A total of 12 studies were selected out of 190 articles on traumatic PTX where conservative treatment and chest tube decompression were compared. Our case report offers a novel contribution by illustrating the successful resolution of a sizable pneumothorax through needle aspiration, suggesting that even a large PTX in a hemodynamically stable patient, without other risk conditions, can be successfully treated conservatively with simple needle aspiration in order to avoid tube thoracostomy complications.

Spontaneous pneumothorax after shoulder arthroscopy under general anesthesia: a case report

A woman in her early 70s presented with a right fifth rib fracture along with left scapular body and glenoid fractures resulting from a traffic accident. She had no history of lung disease. The patient underwent multi-incisional video-guided arthroscopic fracture reduction and screw fixation in the right lateral decubitus position under general anesthesia, and surgery was followed by chest tube insertion. Left-sided pneumothorax was found during routine postoperative radiography despite the absence of relevant symptoms or signs such as hypoxia, chest pain, or respiratory difficulty. We herein report this unusual case with a brief literature review.

Pneumothorax detection with thoracic ultrasound as the method of choice in interventional pulmonology - A retrospective single-center analysis and experience

BACKGROUND

Recent studies have shown that thoracic ultrasound (TUS) is not inferior to chest radiography (CR) in detecting pneumothorax (PTX). It is unclear if adopting TUS can reduce the number of CR in the daily clinical routine. This retrospective study investigates the utilization of post-interventional CR and TUS for PTX detection after the introduction of TUS as the method of choice in an interventional pulmonology unit.

METHODS

All interventions with CR or TUS for ruling out PTX performed in the Pneumology Department of the University Hospital Halle (Germany) 2014 to 2020 were included. The documented TUS and CR performed before (period A) and after the introduction of TUS as the method of choice (period B), as well as the number of diagnosed and missed PTX were recorded.

RESULTS

The study included 754 interventions (110 in period A and 644 in period B). The proportion of CR decreased from 98.2% (n = 108) to 25.8% (n = 166) (p < 0.001). During period B, a total of 29 (4.5%) PTX were diagnosed. Of these, 28 (96.6%) were detected on initial imaging (14 by CR, 14 by TUS ). One PTX (0.2%) was initially missed by TUS, none by CR. Confirmatory investigations were ordered more frequently after TUS (21 of 478, 4.4%) than after CR (3 of 166, 1.8%).

CONCLUSION

The use of TUS in interventional pulmonology can effectively reduce the number of CR and thus save resources. However, CR may still be favored in specific circumstances or if pre-existing conditions limit sonographic findings.

The Global Burden of Pleural Diseases

Pleural diseases include a spectrum of disorders broadly categorized into pneumothorax and pleural effusion. They often cause pain, breathlessness, cough, and reduced quality of life. The global burden of diseases reflects regional differences in conditions and exposures associated with pleural disease, such as smoking, pneumonia, tuberculosis, asbestos, cancer, and organ failure. Disease burden in high-income countries is overrepresented given the availability of data and disease burden in lower-income countries is likely underestimated. In the United States, in 2016, there were 42,215 treat-and-discharge visits to the emergency room for pleural diseases and an additional 361,270 hospitalizations, resulting in a national cost of $10.1 billion.

Bronchial tuberculosis with recurrent spontaneous pneumothorax: A case report

BACKGROUND

Spontaneous pneumothorax associated with tuberculosis due to clinical manifestations, imaging findings and negative pleural biopsy is rare.

CASE REPORT

A 43-year-old young woman went to the hospital several times because of recurrent dyspnea and was diagnosed with a right spontaneous pneumothorax. She underwent multiple closed thoracic drainage procedures, but the pneumothorax was not completely resolved. Pleural biopsy pathology was chronic inflammation; there was no evidence of tuberculosis. A small amount of pneumothorax persisted, intermittent dyspnea became more severe, and pneumothorax increased. Bronchoscopy showed thickening of the left lung lingular segment mucosa, and the bronchial lavage fluid gene X-PERT/rifampicin resistance test was positive. After one month of anti-tuberculosis treatment, the symptoms of short breath were completely relieved, and chest computerized tomography (CT) showed complete resolution of the right pneumothorax.

CONCLUSIONS

When searching for the cause of spontaneous pneumothorax, people should not overlook tuberculosis-related secondary pneumothorax, which should be diagnosed and treated as soon as possible.

Results of the surgical treatment of pulmonary bleb and bullous disease: A retrospective study

Objective

Bullous lung disease is characterised by the development of bullae within the lung parenchyma. Smoking is considered as a main risk factor of bullae formation. The clinical manifestation varies from asymptomatic bullae to severe respiratory distress. The exact medical approach is still controversial. Here, we aimed to evaluate the patient clinical characteristics and the indication of surgery in the patients.

Methods

This study was an analytic cross-sectional study in Razi hospital, Rasht, Iran, in 2016-2020. A total of 110 patients with newly diagnosed lung bullae underwent evaluation based on a checklist, which assessed the variables as clinical characteristics, bullae features, the medical treatment, and its complication. Eventually, statistical analysis was performed by using SPSS v21.0.

Results

: A total of 110 patients were enrolled. All the patients were smokers. In 72.9%, the primary presentation was respiratory distress, which needed surgical resection with no recurrence over 8 months. The clinical manifestation varies from asymptomatic bullae in 4.3% and pneumonia in 34.3% to respiratory distress in 61.4%. There was no statistical correlation between clinical manifestation and all the studied variables excluding respiratory distress (p value: 0.659). Seventy patients underwent surgical treatment, in which 20 cases were complicated by air leak that was managed by the chest tube in 16 patients and the Heimlich valve in four patients. No evidence of recurrence was detected.

Conclusion

The main risk factor of bulla formation is smoking. Because of various clinical presentations, the appropriate medical approach is of paramount importance.

Parameters Affecting Nausea and Vomiting After Thoracoscopic Wedge Resection in Patients With Pneumothorax

BACKGROUND

Postoperative nausea and vomiting (PONV) is one of the complications that can occur frequently in the first 24 hours postoperatively. We aimed to investigate the parameters that could predict PONV in patients who underwent thoracoscopic wedge resection for pneumothorax.

MATERIALS AND METHODS

After obtaining the approval of the ethics committee (ID: 2012-KEAK-15/2358, Date: 14.09.2021), the records of patients who underwent elective video-assisted thoracic surgery (VATS) between January 2018 and June 2021 were analyzed retrospectively. The patients who underwent elective thoracoscopic wedge resection for pneumothorax, who were between the ages of 18-65, American Society of Anesthesiologists (ASA) I-III, and whose body mass index (BMI) was between 18-30 kg/m² were included in the study. However, patients who received a blood transfusion or used antiemetics, anticholinergic drugs, and analgesics continuously were not included. In addition, patients with a history of chronic pain were not included in the study. The patients were divided into two groups, the PONV group (Group 1) and the control group (Group 2). The PONV incidence, visual analog scale (VAS) scores, 24-hour morphine consumption, additional analgesic requirement, neutrophil/lymphocyte ratios (NLR), and platelet/lymphocyte ratios (PLR) were evaluated.

RESULTS

The groups were similar in terms of demographic data (p > 0.05). Additional analgesic requirement and 24-hour morphine consumption were significantly higher in the PONV group (p: 0.005, p < 0.001, respectively). Preoperative NLR (p < 0.001), postoperative NLR (p < 0.001), preoperative PLR (p < 0.022), the VAS scores of the first hour (p: 0.004), and 24^th hour (p < 0.001) were statistically significantly higher in the PONV group compared to the control group.

CONCLUSIONS

NLR parameters can be effective with high sensitivity and specificity in predicting PONV during the preoperative and postoperative period. Besides, preoperative PLR may also be effective in predicting PONV. A treatment that can be planned according to these parameters may play a key role in preventing PONV. In addition, efficient perioperative analgesia management may be effective in reducing PONV by limiting the emetogenic analgesics.

The Role of Ultrasonography in the Diagnosis and Decision Algorithm for the Management of Pneumothorax after Transbronchial Lung Cryobiopsy

BACKGROUND

Pneumothorax is one of the main complications of transbronchial lung cryobiopsy (TBLC). Chest ultrasound (CUS) is a radiation-free alternative method for pneumothorax detection.

OBJECTIVE

We tested CUS diagnostic accuracy for pneumothorax and assessed its role in the decision algorithm for pneumothorax management. Secondary objectives were to evaluate the post-procedure pneumothorax occurrence and risk factors.

METHODS

Eligible patients underwent TBLC, followed by chest X-ray (CXR) evaluation 2 h after the procedure, as our standard protocol. Bedside CUS was performed within 30 min and 2 h after TBLC. Pneumothorax by CUS was defined by the absence of lung sliding and comet-tail artefacts and confirmed with the stratosphere sign on M-mode. Pneumothorax size was determined through lung point projection on CUS and interpleural distance on CXR and properly managed according to clinical status.

RESULTS

Sixty-seven patients were included. Nineteen pneumothoraces were detected at 2 h after the procedure, of which 8 (42.1%) were already present at the first CUS evaluation. All CXR-detected pneumothoraces had a positive CUS detection. There were 3 discordant cases (κ = 0.88, 95% CI: 0.76-1.00, p < 0.001), which were detected by CUS but not by inspiration CXR. We calculated a specificity of 97.5% (95% CI: 86.8-99.9) and a sensitivity of 100% (95% CI: 87.2-100) for CUS. Pneumothorax rate was higher when biopsies were taken in 2 lobes and if histology had pleural representation. Final diagnosis was achieved in 79.1% of patients, with the most frequent diagnosis being hypersensitivity pneumonitis. Regarding patients with large-volume pneumothorax needing drainage, the rate of detection was similar between CUS and CRX.

CONCLUSION

CUS can replace CXR in detecting the presence of pneumothorax after TBLC, and the lung point site can reliably indicate its size. This useful method optimizes time spent at the bronchology unit and allows immediate response in symptomatic patients, helping to choose optimal treatment strategies, while preventing ionizing radiation exposure.

Traumatic Pneumothorax: A Review of Current Diagnostic Practices And Evolving Management

BACKGROUND

Pneumothorax (PTX) is defined as air in the pleural space and is classified as spontaneous or nonspontaneous (traumatic). Traumatic PTX is a common pathology identified in the emergency department. Traditional management calls for chest x-ray (CXR) diagnosis and large-bore tube thoracostomy, although recent literature supports the efficacy of lung ultrasound (US) and more conservative approaches. There is a paucity of cohesive literature on how to best manage the traumatic PTX.

OBJECTIVE OF THE REVIEW

This review aimed to describe current practices and future directions of traumatic PTX management.

DISCUSSION

Lung US has proven to be a potentially more useful tool in the detection of PTX in the trauma bay compared with CXR, and has the potential to become the new gold standard for diagnosing traumatic PTX. Computed tomography remains the ultimate gold standard, although in the setting of trauma, its utility lies more in confirming the presence and measuring the size of a PTX. The traditional mantra calling for large-bore chest tubes as first-line approaches to traumatic PTX is challenged by recent literature demonstrating pigtail catheters as equally efficacious alternatives. In patients with small or occult PTXs, even observation may be reasonable.

CONCLUSIONS

Modern management of the traumatic PTX is shifting toward use of US for diagnosis and more conservative management practices (smaller catheters or observation). Ultimately, this shift is favorable in reducing length of stay, development of complications, and pain in the trauma patient.

Subcutaneous emphysema, pneumothorax and pneumomediastinum as a complication of an asthma attack

Introduction:

Simultaneous subcutaneous emphysema, spontaneous pneumothorax, and pneumomediastinum are complications rarely observed synchronously during an acute exacerbation of bronchial asthma. Although spontaneous pneumothorax has already been reported in asthma patients in the literature, its concurrence with subcutaneous emphysema and pneumomediastinum is extremely rare except for iatrogenic conditions.

Case Study:

We describe a patient who presented to the emergency room with progressive dyspnea and chest pain. Three days before, she consulted her general physician with a history of violent dry cough and wheezing. An acute asthma exacerbation was diagnosed, and an inhaled short-acting beta 2 agonist and oral prednisone were prescribed. The patient developed simultaneous subcutaneous emphysema, spontaneous pneumothorax, and pneumomediastinum, a rare complication of an asthma attack.

Conclusions:

Our aim is to emphasize that occult pneumothoraces should be considered in a patient presenting with an acute asthma attack failing to respond to conventional medical therapy.

Neonatal pneumothorax from the perspective of a pediatric surgeon: classification and management protocol: a preliminary algorithm

Background/aim

Current neonatal pneumothorax classifications based on air volume escaping in pleural space have no contribution on the treatment. Therefore, our aim was to classify neonatal pneumothorax to guide treatment management based on our experiences.

Material and methods

The records of all neonates admitted to our clinics from March 2017 to August 2020 were reviewed. The patients with pneumothorax were identified through the neonatology department patient database search. The study only included the patients with symptomatic pneumothorax and these patients were evaluated into 3 groups based on the changes in peripheral oxygen saturation (SpO2) and clinical features immediately after the tube thoracostomy (TT) procedure. Accordingly, neonatal pneumothorax was divided into 3 types: patients with SpO2 increasing immediately after TT were included in type I, patients whose SpO2 did not change after TT were included in type II, and patients with SpO2 decreasing immediately after TT were included in type III pneumothorax.

Results

A total of 82 patients were included in the study. Sixty-one percent of these patients had type I, 24% had type II, and 15% had type III pneumothorax. None of the neonates died in type I and II pneumothoraces while 9 of 12 neonates (75%) died within the neonatal period in type III pneumothorax. Although we applied treatments such as high-frequency oscillatory ventilation, selective intubation, continuous negative aspiration, and surgical treatment to our patients that were lost due to type III pneumothorax, we were not successful. We successfully managed our surviving type III pneumothorax patients with a simple pressure cycle ventilator, using a combination of high rates, modest peak airway pressures [18 to 22 cm H2O and no positive end-expiratory pressure (PEEP)], and an autologous blood patch.

Conclusion

Classification of pneumothoraces into different types significantly contributes to patient treatment planning through a predetermined strategy, not through trial-and-error. High frequency and zero PEEP ventilation can provide significant improvement in risky cases.

Cannabis Use Is Associated With Recurrence After Primary Spontaneous Pneumothorax

Purpose: Primary spontaneous pneumothorax (PSP) is a frequently encountered entity that carries a high rate of recurrence. The current study aims to investigate if cannabis use at time of initial PSP is associated with disease recurrence.

Methods: Patients presenting with PSP between 2010 and 2018 at a single institution were identified. Exclusion criteria included secondary pneumothorax, severe chronic lung disease, lung cancer, and lost to follow-up. Patients were compared relative to their cannabis usage with Fisher's exact test, Wilcoxon rank-sum test, and logistic regression.

Results: Overall, 67 patients (53 male) met inclusion criteria with a median body mass index (BMI) of 21.5 kg/m² (IQR 19.1–25.2) and age of 34 years (IQR 22–53). Initial treatment consisted of chest tube in 42 patients (63%), video-assisted thoracoscopic surgery wedge resection in 19 patients (28%), and observation in 6 patients (9%). Cannabis users (n = 28; 42%) had a higher rate of tobacco use (79 vs. 38%; p = 0.005), lower BMI [21.0 kg/m² (IQR 18.3–23.1) vs. 22.2 kg/m² (IQR 19.9–28.6), p = 0.037], and were more likely to require intervention at first presentation compared with non-marijuana users. Cannabis use was associated with PSP recurrence when adjusting for tobacco use, BMI, and height (OR 1.85, 95% CI 1.38–18.3, p = 0.014).

Conclusion: There is a high rate of cannabis usage in patients presenting with PSP. Cannabis usage is associated with PSP recurrence and eventual need for operative intervention.

Frequency, Risk Factors, Clinical Characteristics, and Outcomes of Spontaneous Pneumothorax in Patients With Coronavirus Disease 2019: A Case-Control, Emergency Medicine-Based Multicenter Study

BACKGROUND

Recent reports of patients with coronavirus disease 2019 (COVID-19) developing pneumothorax correspond mainly to case reports describing mechanically ventilated patients. The real incidence, clinical characteristics, and outcome of spontaneous pneumothorax (SP) as a form of COVID-19 presentation remain to be defined.

RESEARCH QUESTION

Do the incidence, risk factors, clinical characteristics, and outcomes of SP in patients with COVID-19 attending EDs differ compared with COVID-19 patients without SP and non-COVID-19 patients with SP?

STUDY DESIGN AND METHODS

This case-control study retrospectively reviewed all patients with COVID-19 diagnosed with SP (case group) in 61 Spanish EDs (20% of Spanish EDs) and compared them with two control groups: COVID-19 patients without SP and non-COVID-19 patients with SP. The relative frequencies of SP were estimated in COVID-19 and non-COVID-19 patients in the ED, and annual standardized incidences were estimated for both populations. Comparisons between case subjects and control subjects included 52 clinical, analytical, and radiologic characteristics and four outcomes.

RESULTS

We identified 40 occurrences of SP in 71,904 patients with COVID-19 attending EDs (0.56‰; 95% CI, 0.40‰-0.76‰). This relative frequency was higher than that among non-COVID-19 patients (387 of 1,358,134, 0.28‰; 95% CI, 0.26‰-0.32‰; OR, 1.93; 95% CI, 1.41-2.71). The standardized incidence of SP was also higher in patients with COVID-19 (34.2 vs 8.2/100,000/year; OR, 4.19; 95% CI, 3.64-4.81). Compared with COVID-19 patients without SP, COVID-19 patients developing SP more frequently had dyspnea and chest pain, low pulse oximetry readings, tachypnea, and increased leukocyte count. Compared with non-COVID-19 patients with SP, case subjects differed in 19 clinical variables, the most prominent being a higher frequency of dysgeusia/anosmia, headache, diarrhea, fever, and lymphopenia (all with OR > 10). All the outcomes measured, including in-hospital death, were worse in case subjects than in both control groups.

INTERPRETATION

SP as a form of COVID-19 presentation at the ED is unusual (< 1‰ cases) but is more frequent than in the non-COVID-19 population and could be associated with worse outcomes than SP in non-COVID-19 patients and COVID-19 patients without SP.

Recurrent Spontaneous Pneumothorax in a 47-Year-Old Woman

Pneumothorax is a condition where air exists in the chest cavity, outside the lung. The causes of pneumothorax are numerous and determining the etiology can aid in treatment and prevent recurrence. We describe a 47-year-old female patient with past medical history of endometriosis who presented to the emergency room with recurrent right sided pneumothorax, its onset correlating with onset of menses. She underwent video assisted thorascopic surgery for a suspected catamenial pneumothorax whereby nodular "chocolate" appearing areas were noted on the middle lobe and multiple similar appearing lesions and fenestrations were noted on the diaphragm. A biologic mesh was affixed to the diaphragm after which mechanical and chemical pleurodesis were performed. She tolerated the procedure well and has been symptom free since. Herein, we review the pathophysiology, diagnosis, and treatment strategies for catamenial pneumothorax in the hopes of increasing awareness and understanding of this rare cause of spontaneous pneumothorax.

Pneumothorax in connective tissue disease-associated interstitial lung disease

Background

Spontaneous pneumothorax is a complication that occurs in patients with connective tissue disease-associated interstitial lung disease (CTD-ILD); however, few studies on the clinical implications of pneumothorax for patients with CTD-ILD have been performed.

Objectives

This study aimed to investigate the incidence and prognostic significance of pneumothorax and the risk factors for its onset in patients with CTD-ILD.

Methods

This study included 140 consecutive patients with CTD-ILD. Clinical characteristics, laboratory findings, pulmonary function test results, and chest high-resolution computed tomography (HRCT) images were retrospectively evaluated.

Results

A total of 18 patients (12.9%) developed pneumothorax during their clinical course. The cumulative incidence of pneumothorax from the time of CTD-ILD diagnosis was 6.5%, 8.7%, and 11.3% at 1, 3, and 5 years, respectively. The 10-year survival rate was significantly lower in patients with pneumothorax (29.6%) than that in those without pneumothorax (81.3%). The development of pneumothorax was significantly associated with poor prognosis (HR 22.0; p < 0.010). Furthermore, a lower body mass index, greater extent of reticular abnormalities on HRCT, and administration of methylprednisolone pulse therapy were significantly associated with the development of pneumothorax.

Conclusion

Pneumothorax is a serious complication in the clinical course of patients with CTD-ILD and the onset of pneumothorax predicts a poor outcome.

Predictors of chest drainage of pneumothorax in neonates

This is a retrospective, single-center observational study to explore the predictors of chest drainage for neonatal pneumothorax. A total of 183 neonates (age ≤28 days) who presented to the Children's Hospital of Soochow University between January 1, 2015 and December 31, 2018 for pneumothorax or developed pneumothorax during a hospital stay were included. Demographic data, clinical presentation, and imaging characteristics of neonatal pneumothorax were collected and analyzed. We used univariate and multivariate logistic regression analyses to determine significant predictors of chest drainage of pneumothorax in neonates. Pneumothorax occurred within 24 h after birth in 131 (71.6%) cases, between 24 and 48 h after birth in 41 (22.4%) cases, and 48 h after birth in 11 (6.0%) cases. Univariate and multivariate logistic regression analyses revealed that lung collapse ≥1/3 on initial chest X-ray (OR 4.99, 95%CI 2.25-11.07), chest retractions (OR 8.12, 95%CI 2.88-22.89), cyanosis (OR 2.25, 95%CI 1.08-4.66), and frothing from mouth (OR 2.49, 95%CI 1.12-5.49) (P<0.05 for all) were significant predictors of the need for chest drainage due to pneumothorax. In conclusion, the thorough evaluation of the above predictive factors can guide treatment and improve patient outcome.

What is the best treatment strategy for primary spontaneous pneumothorax? A retrospective study

Background

Several treatment strategies are available for primary spontaneous pneumothorax (PSP). Surgical procedures are also performed in patients with PSP without an absolute indication for surgery. This study was performed to investigate the best treatment strategy for PSP by comparison of the recurrence rate.

Materials and methods

From January 2006 to December 2013, 149 patients with PSP aged ≤50 years were treated in our institution. We reviewed the recurrence rate of PSP for each treatment strategy and evaluated the association between the recurrence rate of PSP with the clinicopathological characteristics. We also compared the surgery and non-surgery groups.

Results

A significant difference in the PSP recurrence rate was found between the surgery and non-surgery groups (22% vs. 52%, respectively; p < 0.001), patients aged ≥22 and < 22 years (16% vs. 44%, respectively; p < 0.001), and smokers and nonsmokers (13% vs. 43%, respectively; p < 0.001). There were also significant differences in the multivariate analysis (p < 0.001, p = 0.050, and p = 0.001, respectively). In the surgery group, the PSP recurrence rate was significantly different between patients aged ≥22 and < 22 years (7% vs. 38%, respectively; p < 0.001) and smokers and nonsmokers (5% vs. 33%, respectively; p = 0.002). No significant differences were found in the non-surgery group.

Conclusions

In the surgical treatment of PSP, it is desirable that smokers stop using tobacco and that patients are ≥22 years old. Moreover, when surgery is being considered, the best timing seems to be when air leakage is present because the air leakage sites can be resected.

The Helpful Role of CD10 and Hormonal Receptors Co-Expression in the Histologic Diagnosis of Catamenial Pneumothorax

The histology in cases of primary spontaneous pneumothorax is generally nonspecific, but a careful examination, taking into account clinical data, may reveal subtle tissue alterations leading to a specific diagnosis in cases that might otherwise be taken as primary and spontaneous. In this article, we describe 3 cases of catamenial pneumothorax histologically demonstrated by the presence of scattered and submillimeter aggregates of bland-looking spindle endometrial stromal cells (so-called "stromal endometriosis") into the visceral pleural layer. The use of CD10 and estrogen and progesterone receptors in lung resection specimens from young women experiencing recurrent pneumothorax is extremely helpful in disclosing endometriosis and confirming a diagnosis of catamenial pneumothorax. A review of the literature on this topic is also presented.

Management of Persistent Air Leaks Using Endobronchial Autologous Blood Patch and Spigot Occlusion: A Multicentre Randomized Controlled Trial in China

BACKGROUND

Optimal management of persistent air leaks (PALs) in patients with secondary spontaneous pneumothorax (SSP) remains controversial.

OBJECTIVE

To evaluate the efficacy and safety of endobronchial autologous blood plus thrombin patch (ABP) and bronchial occlusion using silicone spigots (BOS) in patients with SSP accompanied by alveolar-pleural fistula (APF) and PALs.

METHODS

This prospective multicentre randomized controlled trial compared chest tube-attached water-seal drainage (CTD), ABP, and BOS that were performed between February 2015 and June 2017 in one of six tertiary care hospitals in China. Patients diagnosed with APF experiencing PALs (despite 7 days of CTD) and inoperable patients were included. Outcome measures included success rate of pneumothorax resolution at the end of the observation period (further 14 days), duration of air leak stop, lung expansion, hospital stay, and complications.

RESULTS

In total, 150 subjects were analysed in three groups (CTD, ABP, BOS) of 50 each. At 14 days, 60, 82, and 84% of CTD, ABP, and BOS subjects, respectively, experienced full resolution of pneumothorax (p = 0.008). All duration outcome measures were significantly better in the ABP and BOS groups than in the CTD group (p < 0.016 for all). The incidence of adverse events, including chest pain, cough, and fever, was not significantly different. All subjects in the ABP and BOS groups experienced temporary haemoptysis. Spigot displacement occurred in 8% of BOS subjects.

CONCLUSION

ABP and BOS resulted in clinically meaningful outcomes, including higher success rate, duration of air leak stop, lung expansion, and hospital stay, with an acceptable safety profile.

Contralateral Traumatic Hemopneumothorax

Pneumothorax is the entry of air into the virtual space between the visceral and the parietal pleurae, which can occur spontaneously or to a greater extent in a traumatic way. In daily clinical practice it is frequent to find injuries that generate traumatic pneumothorax that is ipsilateral to the lesion. However, there are case reports of contralateral pneumothorax that occurred in procedures such as insertion of pacemakers, or in cases of pneumonectomy. The following is the case report of a 37-year-old man who was admitted with a sharp wound to the right paravertebral region who developed a left haemopneumothorax due to a tangential course of the injuring agent. Adequate clinical judgment was followed, and several imaging studies were carried out, leading to the diagnosis of traumatic pneumothorax that was contralateral to the described injury.

A Systematic Review and Meta-Analysis Comparing Pigtail Catheter and Chest Tube as the Initial Treatment for Pneumothorax

BACKGROUND

The optimal initial treatment approach for pneumothorax remains controversial. This systemic review and meta-analysis investigated the effectiveness of small-bore pigtail catheter (PC) drainage compared with that of large-bore chest tube (LBCT) drainage as the initial treatment approach for all subtypes of pneumothorax.

METHODS

PubMed and Embase were systematically searched for observational studies and randomized controlled trials published up to October 9, 2017, that compared PC and LBCT as the initial treatment for pneumothorax. The investigative outcomes included success rates, recurrence rates, complication rates, drainage duration, and hospital stay.

RESULTS

Of the 11 included studies (875 patients), the success rate was similar in the PC (79.84%) and LBCT (82.87%) groups, with a risk ratio of 0.99 (95% CI, 0.93 to 1.05; I² = 0%). Specifically, PC drainage was associated with a significantly lower complication rate following spontaneous pneumothorax than LBCT drainage (Peto odds ratio: 0.49 [95% CI, 0.28 to 0.85]; I² = 29%). In the spontaneous subgroup, PC drainage was associated with a significantly shorter drainage duration (mean difference, -1.51 [95% CI, -2.93 to -0.09]) and hospital stay (mean difference: -2.54 [95% CI, -3.16 to -1.92]; P < .001) than the LBCT group.

CONCLUSIONS

Collectively, results of the meta-analysis suggest PC drainage may be considered as the initial treatment option for patients with primary or secondary spontaneous pneumothorax. Ideally, randomized controlled trials are needed to compare PC vs LBCT among different subgroups of patients with pneumothorax, which may ultimately improve clinical care and management for these patients.

TRIAL REGISTRY

PROSPERO; No.: CRD42017078481; URL: https://www.crd.york.ac.uk/prospero/.

A comparison of axillary thoracotomy versus video-assisted thoracoscopic surgery in the surgical treatment of primary spontaneous pneumothorax

Background

This study aims to compare the results of video-assisted thoracoscopic surgery and axillary thoracotomy in the surgical treatment of primary spontaneous pneumothorax.

Methods

Between January 2009 and December 2015, a total of 199 patients (178 males, 21 females; mean age 21.3±7.1 years; range 13 to 35 years) with primary spontaneous pneumothorax who were operated at Dr. Siyami Ersek Thoracic and Cardiovascular Surgery Training and Research Hospital, Department of Thoracic Surgery and Kadikoy and Kozyatagi Acibadem hospitals were retrospectively analyzed. Of these patients, 48 underwent axillary thoracotomy, wedge resection, apical pleurectomy, and tissue adhesives, while 151 were administered videoassisted thoracoscopic surgery, wedge resection, apical pleurectomy, and tissue adhesives. Both groups were compared in terms of age, gender, the amount of long-term analgesic use, duration of surgery, length of hospitalization, recurrence, complication, and mortality rates.

Results

The patients were followed for one year. No mortality was observed in any patient. There was no significant difference in the age and gender distributions of the patients, postoperative length of hospital stay, recurrence rates, and complication rates according to the type of operation. However, the duration of operation was longer in the videoassisted thoracoscopic surgery patients.

Conclusion

Video-assisted thoracoscopic surgery is associated with less pain and higher patient satisfaction and allows returning to daily activities in a shorter time period. Based on our study results, we suggest that video-assisted thoracoscopic surgery is more suitable, compared to axillary thoracotomy, owing to its advantages, such as being less invasive and providing a better angle of view.

High Nrf2 expression in alveolar type I pneumocytes is associated with low recurrences in primary spontaneous pneumothorax

Recurrent primary spontaneous pneumothorax (PSP) is a troublesome problem and a major concern for the patients. This study examined whether nuclear factor erythroid 2-related factor 2 (Nrf2) expression in alveolar type I pneumocytes was associated with the clinical manifestations of PSP patients including disease recurrence. Eighty-eight PSP patients who were managed with needlescopic video-assisted thoracoscopic surgery (NVATS) were included in this study. Immunohistochemistry (IHC) was assessed to determine Nrf2 expression in resected lung tissues and the results were correlated with clinicopathological characteristics by the chi-square or the Fisher's exact test. The prognostic value of Nrf2 for overall recurrence was evaluated by univariate and multivariable Cox regression model. The expression of Nrf2 was observed in type I pneumocytes of lung tissues from PSP patients by IHC. We found that low Nrf2 expression in PSP patients, especially in young (age ≤ 20, p = 0.033) and body mass index (BMI) ≥18 kg/m² (p = 0.019) groups, was significantly correlated with PSP recurrence. In the univariate and multivariate analyses, high Nrf2 expression was a significant protective factor for overall recurrence in PSP patients (univariate: p = 0.026; multivariate: p = 0.004). The expression level of Nrf2 in alveolar type I pneumocytes was a potential factor involved in PSP recurrence. Our findings suggest that elevated Nrf2 expression in PSP patients may be a promising way for reducing PSP recurrence.

An Age-Stratified Longitudinal Study of Primary Spontaneous Pneumothorax

PURPOSE

The objective of this study was to determine the age-stratified incidence, frequency, and duration of recurrence of primary spontaneous pneumothorax (PSP).

METHODS

This study analyzed the epidemiology of PSP among hospitalized patients using the National Health Research Institutes of Taiwan database. The incidence of PSP was determined from a cohort of 19,562 deidentified individuals with PSP between 2001 and 2013. The insurants consisted of 99% of the Taiwan population of about 23 million people. A 5- to 12-year long-term recurrence analysis was based on data from 11,190 patients with PSP between 2001 and 2008.

RESULTS

The incidence of PSP in in-patients increased from 5.05 to 7.18/100,000 in a 13-year analysis. The age group at highest risk was 15-22 years with incidence rates >11/100,000 and readmission rates of 17%-31%. About 20% of patients had more than one attack based on long-term follow-ups. About .8% of patients had more than three hospital admissions. Only 3.9% of patients had repeated or recurrent attacks after more than 4 years. All patients who had been admitted on more than four occasions were adolescents, except for four patients who were aged between 20 and 24 years old.

CONCLUSIONS

Adolescents with PSP had a higher incidence of attacks and more frequent and longer periods of vulnerability to recurrence. The majority of patients experienced recurrence during the first 4 years after the first attack.

Electrocardiographic characteristics in young male patients with left primary spontaneous pneumothorax estimated by the collins equation

OBJECTIVE

To investigate the 12-lead surface electrocardiographic (ECG) findings in young male patients with left primary spontaneous pneumothorax (PSP) estimated by the Collins equation.

METHODS

From 2003 through 2008, 60 young male patients who had left PSP and 61 age-matched unaffected males were included for 12-lead ECG analyses. The PSP size was estimated by the Collins equation. Those with left PSP were divided into two groups: 1) large PSP ≥30% (n=37), and 2) small PSP <30% (n=23). The ECG in the unaffected was used as the normal control. Baseline demographic, anthropometric, and electrocardiographic findings including heart rate, P-QRS-T axes, wave intervals, and RS voltages were compared among three groups.

RESULTS

As compared to the unaffected, patients with left PSP had faster heart rate, longer QTc interval, greater QRS and T axes. With regard to RS amplitudes, greater R in lead aVR and V1, and deeper S in lead II indicating predominant rightward forces, and smaller R in lead I and V3-V6 indicating inferior leftward forces were present in patients with left PSP. Of these ECG findings, heart rate, S voltage in lead II and R voltage in V1 in the large PSP but not in the small PSP had greater values than that in the unaffected group.

CONCLUSION

Among young male patients with left PSP estimated by the Collins method, the ECG showed faster heart beat and predominant rightward forces especially for those with large PSP.

Pneumothorax in a young man with anorexia nervosa

Primary spontaneous pneumothorax (PSP) is defined as a pneumothorax that occurs in the absence of an external cause in an individual without underlying generalized lung disease. A number of factors are important and should be carefully considered in the pathogenesis of PSP. This is the first case report of a PSP in a severely malnourished adolescent male with anorexia nervosa (AN) who was involved in excessive physical activity. Clinicians caring for adolescents with AN and vigorous exercise need to be aware of the risk factors associated with the development of a PSP. © 2016 Wiley Periodicals, Inc.(Int J Eat Disord 2016; 49:895-898).

Anesthetic Complication during Maxillofacial Trauma Surgery: A Case Report of Intraoperative Tension Pneumothorax

Tension pneumothorax is a life-threatening emergency that requires a high index of suspension and immediate intervention to prevent circulatory collapse and death. Only five cases of pneumothorax were described in the Oral and Maxillofacial Surgery literature. All cases were postoperative complications associated with orthognathic surgery. We report a case of intraoperative tension pneumothorax during a routine facial trauma surgery requiring emergency chest decompression. The possible causes, classification, and reported cases will be presented.

Ascertainment correction in frailty models for recurrent events data

In retrospective studies involving recurrent events, it is common to select individuals based on their event history up to the time of selection. In this case, the ascertained subjects might not be representative for the target population, and the analysis should take the selection mechanism into account. The purpose of this paper is two-fold. First, to study what happens when the data analysis is not adjusted for the selection and second, to propose a corrected analysis. Under the Andersen-Gill and shared frailty regression models, we show that the estimators of covariate effects, incidence, and frailty variance can be biased if the ascertainment is ignored, and we show that with a simple adjustment of the likelihood, unbiased and consistent estimators are obtained. The proposed method is assessed by a simulation study and is illustrated on a data set comprising recurrent pneumothoraces. Copyright © 2016 John Wiley & Sons, Ltd.

Incidence of pneumothorax during tissue expander-implant reconstruction and algorithm for intraoperative management

BACKGROUND

Iatrogenic pneumothorax is a serious intraoperative complication of immediate breast reconstruction with tissue expanders. However, there is paucity of literature regarding incidence or management of intraoperative pneumothorax in the breast reconstruction patient population.

METHODS

We performed a retrospective chart review on prospectively collected data from all patients undergoing immediate breast reconstruction with tissue expanders from 1992 to 2012 to determine institutional incidence. We also searched the Nationwide Inpatient Sample database from 1998 to 2008 to determine national incidence.

RESULTS

A total of 9653 tissue expanders were placed in 6955 patients at the Memorial Sloan Kettering Cancer Center between 1992 and 2012. There were 3 cases of pneumothorax during immediate breast reconstruction with tissue expanders. The incidence of pneumothorax is 0.03% per expander and 0.04% per patient. From the national database, there were 153 cases of pneumothorax during immediate breast reconstruction with tissue expanders in 27,612 patients. The overall national incidence of pneumothorax is 0.55% per patient.

CONCLUSIONS

Our algorithm for management includes a thoracic surgery consultation intraoperatively. A chest tube should be placed at a site distal to the pleurotomy. The site of injury should be repaired primarily or patched as necessary. If the patient remains stable, it is safe to proceed with placement of the tissue expander.

Spontaneous pneumothorax in children - management, results, and review of the literature

Introduction

Primary spontaneous pneumothorax (PSP) occurs at a frequency of 7.4-18 cases per 100 000 population per year. The PSP typically occurs in young adults and is uncommon in children. The aim of this study was to review our institutional experience with PSP in children.

Material and methods

Twenty-two paediatric patients with confirmed PSP, treated from 2004 to 2014 at the Paediatric Surgery Clinic. There were 18 boys and 4 girls. The mean age was 16 years, 6 months ± 1 month (range 14-17). The mean body mass index (BMI) was 20.1 (ranging from 17 to 24).

Results

The recurrence rate of PSP was 48%. The mean interval of the recurrence was 5 months ± 1 month (range from 3 weeks to 2 years). Recurrent pneumothorax was evacuated by thoracostomy with success in four patients. The first video-assisted thoracoscopic surgery (VATS) procedure had a failure rate of 50%. After second VATS procedure, we did not observe recurrent PSP in two patients. One patient with recurrent PSP, after two VATS procedures, was treated with success, with an open mini axillary thoracotomy. The mean follow-up period was 4 years 3 months ± 1 month (range 6 months – 10 years). We have not noted any intraoperative complications.

Conclusions

Although our study is limited by the small number of patients, we conclude that most patients resolve their spontaneous pneumothorax and air leak with tube thoracostomy alone. For those patients in whom chest tube drainage is not effective, and for those with recurrent PSP, early VATS and bullectomy combined with pleural abrasion is the most efficient intervention.

Pleural puncture that excludes the ablation zone decreases the risk of pneumothorax after percutaneous microwave ablation in porcine lung

PURPOSE

To test the hypothesis that the geometry of probe placement with respect to the pleural puncture site affects the risk of pneumothorax after microwave (MW) ablation in the lung.

MATERIALS AND METHODS

Computed tomography-guided MW ablation of the lung was performed in 8 swine under general anesthesia and mechanical ventilation. The orientation of the 17-gauge probe was either perpendicular (90°) or parallel (< 30°) with respect to the pleural puncture site, and the ablation power was 30 W or 65 W for 5 minutes. After MW ablation, swine were euthanized, and histopathologic changes were assessed. Frequency and factors affecting pneumothorax were evaluated by multivariate analysis.

RESULTS

Among 62 lung MW ablations, 13 (21%) pneumothoraces occurred. No statistically significant difference was noted in the rate of pneumothorax between the perpendicular and the parallel orientations of the probe (31% vs 14%; odds ratio [OR], 2.8; P = .11). The pneumothorax rate was equal for 65-W and 30-W ablation powers (21% and 21%; OR, 1.0; P = .94). Under multivariate analysis, 2 factors were independent positive predictors of pneumothorax: ablation zone inclusive of pleural insertion point (OR, 7.7; P = .02) and time since intubation (hours) (OR, 2.7; P = .02).

CONCLUSIONS

Geometries where the pleural puncture site excluded the ablation zone decreased pneumothorax in swine undergoing MW ablation in the lung. Treatment planning to ensure that the pleural puncture site excludes the subsequent ablation zone may reduce the rate of pneumothorax in patients undergoing MW ablation in the lung.

Favourable experience with m-mode sonography in the diagnosis of pneumothorax in two patients with thoracic subcutaneous emphysema

Introduction. Thoracic subcutaneous emphysema may be caused by various pathologies. In mechanically ventilated patients, timely diagnostic workup is particularly important, as the presence of subcutaneous surgical emphysema may indicate pneumothorax, representing a risk factor for the development of life threatening tension pneumothorax. Thoracic ultrasound is of proven value for the detection of pneumothorax but has so far been considered of little value in the context of subcutaeneous emphysema, due to poor visibility of anatomic structures. Case Presentation. We present the successful use of diagnostic M-mode sonography in two mechanically ventilated patients who developed thoracic subcutaneous emphysema. In both cases B-mode sonography was inconclusive. Conclusion. M-mode sonography may be more sensitive than B-mode sonography in the detection of lung sliding and could become a useful diagnostic tool when pneumothorax needs to be ruled in or ruled out and visibility of the pleura is limited.

Pneumothorax risk factors in smokers with and without chronic obstructive pulmonary disease

RATIONALE

The demographic, physiological, and computed tomography (CT) features associated with pneumothorax in smokers with and without chronic obstructive pulmonary disease (COPD) are not clearly defined.

OBJECTIVES

We evaluated the hypothesis that pneumothorax in smokers is associated with male sex, tall and thin stature, airflow obstruction, and increased total and subpleural emphysema.

METHODS

The study included smokers with and without COPD from the COPDGene Study, with quantitative chest CT analysis. Pleural-based emphysema was assessed on the basis of local histogram measures of emphysema. Pneumothorax history was defined by subject self-report.

MEASUREMENTS AND MAIN RESULTS

Pneumothorax was reported in 286 (3.2%) of 9,062 participants. In all participants, risk of prior pneumothorax was significantly higher in men (odds ratio [OR], 1.55; 95% confidence interval [CI], 1.08-2.22) and non-Hispanic white subjects (OR, 1.90; 95% CI, 1.34-2.69). Risk of prior pneumothorax was associated with increased percent CT emphysema in all participants and participants with COPD (OR, 1.04 for each 1% increase in emphysema; 95% CI, 1.03-1.06). Increased pleural-based emphysema was independently associated with risk of past pneumothorax in all participants (OR, 1.05 for each 1% increase; 95% CI, 1.01-1.10). In smokers with normal spirometry, risk of past pneumothorax was associated with non-Hispanic white race and lifetime smoking intensity (OR, 1.20 for every 10 pack-years; 95% CI, 1.09-1.33).

CONCLUSIONS

Among smokers, pneumothorax is associated with male sex, non-Hispanic white race, and increased percentage of total and subpleural CT emphysema. Pneumothorax was not independently associated with height or lung function, even in participants with COPD. Clinical trial registered with www.clinicaltrials.gov (NCT00608764).

Current practice of lung ultrasonography (LUS) in the diagnosis of pneumothorax: a survey of physician sonographers in Germany

BACKGROUND

The purpose of this study was to survey the current practice of the use of lung ultrasonography (LUS) in the diagnosis of pneumothorax.

METHODS

Physician sonographers, accredited for diagnostic ultrasonography in surgery, anaesthesia and medicine were studied. Questions addressed the frequency of exposure to patients with suspected pneumothorax, frequency of LUS use, preferences regarding technical aspects of LUS examination, assessment of diagnostic accuracy of LUS and involvement in teaching.

RESULTS

Of the respondents, 55.1% used LUS 'always' or 'frequently' for suspected pneumothorax. Also, 35.5% of physicians rated LUS as 'always reliable' in ruling out pneumothorax, and 21.3% of respondents rated LUS as 'always reliable' in ruling in pneumothorax. The mode of performing LUS for pneumothorax was highly variable. Statistically significant differences were found regarding the likelihood of LUS usage, the combined use of M-Mode and B-mode scanning and the confidence to exclude pneumothorax based on LUS findings for physicians with frequent exposure to pneumothorax cases.

CONCLUSIONS

Physicians' use of LUS in the diagnosis of pneumothorax is modest. Confidence in diagnostic accuracy is not comprehensive. Further research is required to establish the most efficient way of performing LUS in this scenario to achieve the highest possible diagnostic accuracy and reliable documentation of examination results.

Overexpression of matrix metalloproteinases in lung tissue of patients with primary spontaneous pneumothorax

BACKGROUND

Although blebs and bullae are frequently found in the apexes of lungs of patients with primary spontaneous pneumothorax (PSP), its pathogens remain unclear.

OBJECTIVES

To examine the role of proteases [matrix metalloproteinase (MMP)-2, MMP-7 and MMP-9] and antiproteases [tissue inhibitors of metalloproteinase (TIMP)-1, TIMP-2, TIMP-3 and TIMP-4] in the pathogenesis of PSP.

METHOD

Fifty consecutive PSP patients who received standard surgical care were enrolled in the study. Lung tissues from 20 patients with stage I non-small cell lung cancer were used as a control. Immunohistochemistry (IHC), reverse transcription-polymerase chain reaction (RT-PCR) and gelatin zymography were used to evaluate the expression of MMP and TIMP in the lung tissue of patients with PSP.

RESULTS

Overexpression of MMP-2, MMP-7 and MMP-9 was found in the afflicted lung by IHC, zymography and RT-PCR. By IHC, higher expression of MMP-2 and MMP-9 in PSP patients was identified in alveolar macrophages and type II pneumocytes (88 and 92% of patients in macrophages, and 72 and 70% of patients in type II pneumocytes, respectively). MMP-2, MMP-7 and MMP-9 expression in patients was higher in mesothelial cells (66, 76 and 76%). Overexpression of TIMP-2 was detected in the extracellular matrix around bullae and blebs. Expression levels of TIMP-1, TIMP-3 and TIMP-4 were negligible (<10% of cells) in both PSP patients and controls.

CONCLUSIONS

MMP-2, MMP-9, MMP-7 and TIMP-2 were upregulated in PSP lesions. These results suggest that an imbalance between the expression of proteases and antiproteases may be involved in the pathogeneses of PSP.

Spontaneous Pneumomediastinum, Pneumopericardium, and Pneumothorax with Respiratory Failure in a Patient with AIDS and Pneumocystis jirovecii Pneumonia

Spontaneous pneumothorax occurs in up to 35% of patients with Pneumocystis jirovecii pneumonia. However, spontaneous pneumomediastinum and pneumopericardium are uncommon complications in patients infected with human immunodeficiency virus, with no reported incidence rates, even among patients with acquired immunodeficiency syndrome (AIDS) and P. jirovecii pneumonia. We report a case of spontaneous pneumomediastinum, pneumopericardium, and pneumothorax with respiratory failure during treatment of P. jirovecii pneumonia in a patient with AIDS; the P. jirovecii infection was confirmed by performing methenamine silver staining of bronchoalveolar lavage specimens. This case suggests that spontaneous pneumomediastinum and pneumopericardium should be considered in patients with AIDS and P. jirovecii pneumonia.

Semi-quantification of pneumothorax volume by lung ultrasound

BACKGROUND

Lung ultrasound (LUS) may accurately diagnose pneumothorax. However, there is uncertainty about its usefulness in the quantification of pneumothorax size. To determine the ability of LUS in the semi-quantification of pneumothorax volume, we compared the projection of the lung point (LP) with the pneumothorax volume measured by computerized tomography (CT) and the interpleural distance on chest radiography (CXR).

METHODS

We performed LUS in patients with pneumothorax and all the LP located on the chest wall were compared to CXR and CT studies. The primary outcome of the study was the ability of LP to grade pneumothorax volumes measured by CT. The secondary outcome was the accuracy of LP to predict small and large pneumothorax according to the societal guidelines based on CXR reading.

RESULTS

A total of 124 patients with pneumothorax were enrolled (76 spontaneous, 20 traumatic and 28 post-procedural). Ninety-four CXR and 58 CT were available for the analysis. An LP posterior to the mid axillary line corresponded to three different CXR criteria for large pneumothorax with sensitivity from 81.4 to 88.2 % and specificity from 64.7 to 72.6 %. The mid axillary line also represented the limit for predicting greater than 15 % of lung collapse when volume is measured at CT, with sensitivity 83.3 % and specificity 82.4 %.

CONCLUSIONS

LUS-targeted assessment of LP was a useful predictor of pneumothorax volume in this research study setting. LUS reliably classified pneumothorax size when compared to criteria based on CXR reading, particularly the small sized pneumothorax. However, LUS greatly outperformed conventional CXR reading for a graded quantification of the percentage of lung collapse.

Pneumothorax and asthma

This review is focused on the relationship between asthma, pneumothorax and pneumomediastinum while presenting a number of case reports that include these conditions. The association between pneumothorax and asthma is not widely known. While asthma includes a common disorder and is prevalent worldwide, its morbidity and mortality is high when is associated with pneumothorax. Furthermore, the delayed diagnosis of pneumothorax while focusing on asthma includes the higher risk of coincidental pneumothorax in asthmatic patients. In addition, pneumomediastinum is considered benign and self-limiting condition that responds to conservative therapy. Although it is rare, the concurrence of pneumomediastinum with pneumothorax may prove fatal during a serious asthma attack. In conclusion, the symptoms of chest pain, dyspnea or focal chest findings when presented in asthmatic patients, must always create suspicion of pneumothorax or pneumomediastinum to the physician.

Use of multidetector computed tomography to guide management of pneumothorax

PURPOSE OF REVIEW

Pneumothorax, a potentially life-threatening condition, is present in about one-third of chest trauma patients. Traditionally, pneumothorax has been diagnosed and managed by use of chest radiography, which has been found inaccurate and inconsistent. With the ubiquitous application of multidetector computed tomography (MDCT) in emergency care, MDCT quantification of pneumothoraces becomes an emerging technique for accurate determination of the size of pneumothoraces. The use of MDCT quantification provides a promising means to improve pneumothorax management.

RECENT FINDINGS

Recent studies have demonstrated that MDCT is the gold standard for detecting pneumothorax and MDCT provides an effective imaging modality for the accurate measurement of the volume of pneumothoraces. The use of MDCT volumetric quantification of pneumothoraces has been evidenced in the improvement of performance in pneumothorax management for clinically stable chest trauma patients.

SUMMARY

The MDCT volumetric quantification of pneumothoraces is a new concept in the care of chest trauma patients and has the potential to improve pneumothorax management. Further clinical studies are needed to establish a MDCT-based clinical guideline for pneumothorax management.

Diagnosis and treatment of pneumothorax

Many diagnostic and therapeutic options exist for the evaluation and treatment of patients with pneumothorax. Guidelines from US and European professional societies and individual expert opinions differ in the approach to patient care. Advances in diagnostic techniques, such as real-time thoracic ultrasound, have added to the evaluation strategy. It is important for medical trainees and providers to become familiar with techniques utilized worldwide as they may be encountered in clinical practice. We review current evidence, expert recommendations, and compare professional society guidelines discussing the various diagnostic and management options for patients with pneumothorax to assist physicians and trainees involved in the care of hospitalized and outpatient adults who have primary, secondary, and traumatic iatrogenic pneumothorax. Management of traumatic non-iatrogenic pneumothorax is beyond the scope of this article, thus, not reviewed here.

Managing iatrogenic pneumothorax and chest tubes

Iatrogenic pneumothorax has become an increasingly recognized complication of routine outpatient procedures, such as transthoracic needle biopsies of the lung and transbronchial lung biopsies. Patients with clinically significant pneumothorax are typically managed with evacuation via a percutaneously placed catheter or chest tube. Tube thoracotomy and chest tube management have traditionally been performed by cardiothoracic surgeons; however, with the increasing number of interventional radiologists and interventional pulmonologists, more chest tubes are being placed by specialists who do not admit and manage patients in the hospital setting. The responsibility for the admission of these patients to the hospital service has fallen to the internist. Hospitalists caring for such patients are often expected to manage the chest tube. General internal medicine training and the existing medical literature provide few guidelines to assist with this issue. We present a discussion of the current published literature and our management algorithms for hospitalists caring for patients admitted with iatrogenic pneumothorax.