Pneumothorax

The risk of secondary spontaneous pneumothorax in patients with chronic obstructive pulmonary disease in Taiwan

INTRODUCTION

Secondary spontaneous pneumothorax (SSP) is often linked to chronic obstructive pulmonary disease (COPD). The frequency of SSP occurrence in COPD patients varies among different research findings. SSPs are more commonly found in the elderly population diagnosed with COPD. Previous studies have reported a pneumothorax rate of 26 per 100,000 COPD patients. There is, however, a notable lack of detailed epidemiological information regarding SSP in Asia. Our study focused on determining the occurrence rate of SSP among COPD patients in Taiwan using an extensive national database. Additionally, this study aimed to identify comorbidities associated with SSP in this patient group.

METHODS

In this study, we used the Longitudinal Health Insurance Database, which contains records of 2 million people who were randomly chosen from among the beneficiaries of the Taiwan National Health Insurance program. The dataset includes information from 2005 to the end of 2017. Our focus was on individuals diagnosed with COPD, identified through ICD-9-CM codes in at least one hospital admission or two outpatient services, with the COPD diagnosis date as the index date. The exclusion criteria included individuals younger than 40 years, those with incomplete records, or those with a previous diagnosis of pneumothorax before the index date. We conducted a matched comparison by pairing COPD patients with control subjects of similar age, sex, and comorbidities using propensity score matching. The follow-up for all participants started from their index date and continued until they developed pneumothorax, reached the study's end, withdrew from the insurance program, or passed away. The primary objective was to evaluate and compare the incidence of pneumothorax between COPD patients and matched controls.

RESULTS

We enrolled 65,063 patients who were diagnosed with COPD. Their mean age (±SD) was 66.28 (±12.99) years, and approximately 60 % were male. During the follow-up period, pneumothorax occurred in 607 patients, equivalent to 9.3 % of the cohort. The incidence rate of SSP in COPD patients was 12.10 per 10,000 person-years, whereas it was 6.68 per 10,000 person-years in those without COPD. Furthermore, COPD patients with comorbidities such as atrial fibrillation, congestive heart failure, coronary artery disease, diabetes mellitus, hypertension, and cancer exhibited an increased incidence of SSP compared to COPD patients without such comorbidities. This was observed after conducting a multivariable Cox regression analysis adjusted for age, sex, and other comorbidities.

CONCLUSION

Our study revealed an elevated risk of SSP in patients with COPD. It has also been suggested that COPD patients with comorbidities, such as atrial fibrillation, congestive heart failure, coronary artery disease, diabetes mellitus, hypertension, and cancer, have an increased risk of developing SSP.

Fleischner Society: Glossary of Terms for Thoracic Imaging

Members of the Fleischner Society have compiled a glossary of terms for thoracic imaging that replaces previous glossaries published in 1984, 1996, and 2008, respectively. The impetus to update the previous version arose from multiple considerations. These include an awareness that new terms and concepts have emerged, others have become obsolete, and the usage of some terms has either changed or become inconsistent to a degree that warranted a new definition. This latest glossary is focused on terms of clinical importance and on those whose meaning may be perceived as vague or ambiguous. As with previous versions, the aim of the present glossary is to establish standardization of terminology for thoracic radiology and, thereby, to facilitate communications between radiologists and clinicians. Moreover, the present glossary aims to contribute to a more stringent use of terminology, increasingly required for structured reporting and accurate searches in large databases. Compared with the previous version, the number of images (chest radiography and CT) in the current version has substantially increased. The authors hope that this will enhance its educational and practical value. All definitions and images are hyperlinked throughout the text. Click on each figure callout to view corresponding image. © RSNA, 2024 Supplemental material is available for this article. See also the editorials by Bhalla and Powell in this issue.

Bronchopleural fistula associated persistent pneumothorax in a patient recovering from COVID-19 pneumonia: A case report

Key Clinical Message

Pneumothorax and bronchopleural fistula (BPF) are potentially fatal complications that can occur in patients with COVID-19 pneumonia. Early detection, appropriate treatment, and consideration of surgical intervention are necessary for optimum outcomes.

Abstract

Introduction

Healthcare professionals face complex challenges as a result of the rare emergence of pneumothorax among the variety of COVID-19 complications, including severe viral pneumonia.

Case History

A 57-year-old male with multiple comorbidities diagnosed with COVID-19 pneumonia was admitted to our center and exhibited bilateral crepitations. During hospitalization, the patient developed right-sided pneumothorax that persisted despite chest tube insertion was linked to the presence of BPF.

Discussion

The occurrence of pneumothorax in COVID-19 patients is relatively rare risk factors for which are not yet fully understood, although smoking history may play a role. Conservative management is recommended for asymptomatic cases, while intercostal drainage is necessary for symptomatic patients. Surgical intervention may be required to manage the BPF in some instances.

Conclusion

Pneumothorax and BPF are rare but potentially life-threatening complications in patients recovering from COVID-19 pneumonia. Early recognition, appropriate treatment, and consideration of surgical intervention are crucial for optimizing patient outcomes.

Application of Deep Learning Techniques for Detection of Pneumothorax in Chest Radiographs

With the advent of Artificial Intelligence (AI) and even more so recently in the field of Machine Learning (ML), there has been rapid progress across the field. One of the prominent examples is image recognition in the medical category, such as X-ray imaging, Computed Tomography (CT), and Magnetic Resonance Imaging (MRI). It has the potential to alleviate a doctor's heavy workload of sifting through large quantities of images. Due to the rising attention to lung-related diseases, such as pneumothorax and nodules, ML is being incorporated into the field in the hope of alleviating the already strained medical resources. In this study, we proposed a system that can detect pneumothorax diseases reliably. By comparing multiple models and hyperparameter configurations, we recommend a model for hospitals, as its focus on minimizing false positives aligns with the precision required by medical professionals. Through our cooperation with Poh-Ai Hospital, we acquired a total of over 8000 X-ray images, with more than 1000 of them from pneumothorax patients. We hope that by integrating AI systems into the automated process of scanning chest X-ray images with various diseases, more resources will be available in the already strained medical systems. Our proposed system showed that the best model that is used for transfer learning from our dataset performed with an AP of 51.57 and an AP75 of 61.40, with accuracy at 93.89%, a false positive of 1.12%, and a false negative of 4.99%. Based on the feedback from practicing doctors, they are more wary of false positives. For their use case, we recommend another model due to the lower false positive rate and higher accuracy compared with other models, which in our test shows a rate of only 0.88% and 95.68%, demonstrating the feasibility of the research. This promising result showed that it could be utilized in other types of diseases and expand to more hospitals and medical organizations, potentially benefitting more people.

DAWTran: dynamic adaptive windowing transformer network for pneumothorax segmentation with implicit feature alignment

Objective. This study aims to address the significant challenges posed by pneumothorax segmentation in computed tomography images due to the resemblance between pneumothorax regions and gas-containing structures such as the trachea and bronchus.Approach. We introduce a novel dynamic adaptive windowing transformer (DAWTran) network incorporating implicit feature alignment for precise pneumothorax segmentation. The DAWTran network consists of an encoder module, which employs a DAWTran, and a decoder module. We have proposed a unique dynamic adaptive windowing strategy that enables multi-head self-attention to effectively capture multi-scale information. The decoder module incorporates an implicit feature alignment function to minimize information deviation. Moreover, we utilize a hybrid loss function to address the imbalance between positive and negative samples.Main results. Our experimental results demonstrate that the DAWTran network significantly improves the segmentation performance. Specifically, it achieves a higher dice similarity coefficient (DSC) of 91.35% (a larger DSC value implies better performance), showing an increase of 2.21% compared to the TransUNet method. Meanwhile, it significantly reduces the Hausdorff distance (HD) to 8.06 mm (a smaller HD value implies better performance), reflecting a reduction of 29.92% in comparison to the TransUNet method. Incorporating the dynamic adaptive windowing (DAW) mechanism has proven to enhance DAWTran's performance, leading to a 4.53% increase in DSC and a 15.85% reduction in HD as compared to SwinUnet. The application of the implicit feature alignment (IFA) further improves the segmentation accuracy, increasing the DSC by an additional 0.11% and reducing the HD by another 10.01% compared to the model only employing DAW.Significance. These results highlight the potential of the DAWTran network for accurate pneumothorax segmentation in clinical applications, suggesting that it could be an invaluable tool in improving the precision and effectiveness of diagnosis and treatment in related healthcare scenarios. The improved segmentation performance with the inclusion of DAW and IFA validates the effectiveness of our proposed model and its components.

Use of Video-Assisted Thoracoscopic Surgery (VATS) in the Treatment of Primary Spontaneous Pneumothorax (PSP) in Children

INTRODUCTION

This study aims to review the primary spontaneous pneumothorax (PSP) patients we have treated and to discuss the results in terms of PSP treatment management and video-assisted thoracoscopic surgery (VATS) use in the light of the literature.

METHODS

The study was designed retrospectively and conducted at a tertiary referral university hospital between January 1, 2015 and May 1, 2021. Patients under the age of 18 years with a diagnosis of pneumothorax (PTX) were included in the study. Medical records were analyzed in terms of clinical characteristics, demographic data, findings from imaging data, procedures performed, and course of the disease at hospital. Patients with no evidence of PTX on radiologic imaging (direct postero-anterior chest X-ray (PACXR) or thoracic computed tomography (TCT)), incomplete medical records for follow-up, history of trauma, and neonatal PTX were excluded from the study.

RESULTS

The study was conducted on a total of 98 PTX cases in 69 patients, 61 (88.4%) males and eight (11.6%) females. The ages of the patients ranged between 13 and 17 years with a mean of 16.59 ± 0.95 years. While 48 (49%) PTX cases were treated with tube thoracostomy, 19 (19.4%) were treated with medical follow-up (nonsurgical treatment) and 31 (31.6%) were treated with VATS. A total of 31 VATS procedures were performed on 28 patients. The follow-up period after VATS ranged from tthree to 78 months, with a mean of 31.5 ± 20.3 months and a median of 28 months.

CONCLUSION

 Our retrospective study showed that TCT scanning did not provide additional benefit when PSP was detected on PACXR in patients presenting with chest pain and respiratory distress. According to the findings of our study, it was thought that the probability of undergoing an invasive procedure and surgical intervention increased as the percentage of PTX detected in PACXR increased. Tube thoracostomy may be required in a patient with PSP if PTX does not start to decrease and lung expansion does not increase after an average of 60 hours after the decision for medical follow-up, and if PTX is progressive in the follow-up. VATS can be performed on a patient with PSP when lung expansion does not increase after an average of 18 hours after tube thoracostomy, when PTX progresses, when air leakage continues for more than 10 days despite increased lung expansion, and when recurrent PTX occurs.

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.

The Descriptive Features of Primary Spontaneous Pneumothorax Patients in King Abdulaziz Medical City, Riyadh, Saudi Arabia

Background Primary spontaneous pneumothorax (PSP) is a fairly prevalent disorder in emergency medicine. PSP most frequently affects tall, thin male smokers and is most prevalent during adolescence. Published literature contains a wide range of Primary Spontaneous Pneumothorax (PSP) recurrence rates, but there is limited information on the variables affecting recurrence. Objective To identify the descriptive features of PSP in King Abdulaziz Medical City, Riyadh, Saudi Arabia. Methods This retrospective cross-sectional study was conducted in Surgery King Abdulaziz Medical City, Riyadh, Saudi Arabia. Including all PSP patients from 2016-2021, excluding pediatric and geriatric patients. Participants were selected using a simple random sampling technique, and data were collected from hospital records. Data analysis was conducted by using SPSS. Results In this study, we included a total of 131 participants. Most were males (93.1%), and most were aged between 21-30 years. Our findings showed that most PSP events occurred in winter (28.6%). Followed by fall (25.7%), summer (25.0%), and spring (20.7%). Concerning the smoking status of our respondents, our results revealed that most of them were active smokers (72.5%). Left-PSP was the most commonly reported type of PSP (43.5 %), followed by right-PSP (38.9%), non-simultaneous bilateral PSP (14.5%), and bilateral simultaneous PSP (3.1%). Moreover, we found that the recurrence rate of PSP was 42%. Regarding the management of PSP, almost half of the respondents were managed initially by Chest tube. The most frequently used surgical option was VATS- Bullectomy with Abrasion Pleurodesis. Finally, the recurrence rate of PSP was 42% among the patients. The percentage of patients with one recurrence only was 65.5% among the patients with recurrent PSP, second recurrence at 29.1%. Third, Fourth, and Fifth had the same recurrence percentage of 1.8%, and these percentages came to be statistically significant. (P value < 0.001) Conclusion Our study concluded that PSP was more prevalent in tall, thin, young male smokers. Almost half of the respondents suffered from at least one recurrence attack of PSP. The majority of the patients with recurrences experienced one recurrence only, and the second recurrence was estimated to be almost one-third. There is no significant association between the occurrence and seasons of the attack at a time. Most of the participants were managed initially by a chest tube. The most frequently used surgical option was Video Assisted Thoracoscopic Surgery (VATS) with abrasion pleurodesis.

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.

[Internal differential diagnoses in acute back pain : An internal perspective on the possible causes of acute back pain]

The majority of patients with acute back pain have no serious underlying disease; however, many internal diseases can be manifested as acute or chronic back pain. Therefore, in the assessment of patients with back pain the clinical history and clinical examination are important in order to detect indications for a possible underlying disease. Particularly red flags that indicate an acute or life-threatening disease should not be missed. In most cases where such red flags, risk factors or clinical indications are not present, no systematic search for internal underlying diseases is necessary. This article summarizes the most relevant differential diagnoses and clinical indications as well as warning symptoms.

European Pediatric Surgeons' Association Survey on the Management of Primary Spontaneous Pneumothorax in Children

AIM

 To evaluate the practice patterns of the European Pediatric Surgeons' Association (EUPSA) members regarding the management of primary spontaneous pneumothorax (PSP) in children.

METHODS

 An online survey was distributed to all members of EUPSA.

RESULTS

 In total, 131 members from 44 countries participated in the survey. Interventional approach (78%) is the most common choice of treatment in the first episode, and most commonly, chest tube insertion (71%) is performed. In the case of a respiratory stable patient, 60% of the responders insert chest tubes if the pneumothorax is more than 2 cm. While 49% of surgeons prefer surgical intervention in the second episode, 42% still prefer chest tube insertion. Main indications for surgical treatment were the presence of bullae more than 2 cm (77%), and recurrent pneumothorax (76%). Eighty-four percent of surgeons prefer thoracoscopy and perform excision of bullae with safe margins (91%). To prevent recurrences, 54% of surgeons perform surgical pleurodesis with pleural abrasion (55%) and partial pleurectomy (22%). The responders who perform thoracoscopy use more surgical pleurodesis and prefer shorter chest tube duration than the surgeons performing open surgery (p < 0.05).

CONCLUSION

 Most of the responders prefer chest tube insertion in the management of first episode of PSP and perform surgical treatment in the second episode in case of underlying bullae more than 2 cm and recurrent pneumothorax. The surgeons performing thoracoscopy use more surgical pleurodesis and prefer shorter chest tube duration than the responders performing open surgery. The development of evidence-based guidelines may help standardize care and improve outcomes in children with PSP.

Quantitative Measurement of Pneumothorax Using Artificial Intelligence Management Model and Clinical Application

Artificial intelligence (AI) techniques can be a solution for delayed or misdiagnosed pneumothorax. This study developed, a deep-learning-based AI model to estimate the pneumothorax amount on a chest radiograph and applied it to a treatment algorithm developed by experienced thoracic surgeons. U-net performed semantic segmentation and classification of pneumothorax and non-pneumothorax areas. The pneumothorax amount was measured using chest computed tomography (volume ratio, gold standard) and chest radiographs (area ratio, true label) and calculated using the AI model (area ratio, predicted label). Each value was compared and analyzed based on clinical outcomes. The study included 96 patients, of which 67 comprised the training set and the others the test set. The AI model showed an accuracy of 97.8%, sensitivity of 69.2%, a negative predictive value of 99.1%, and a dice similarity coefficient of 61.8%. In the test set, the average amount of pneumothorax was 15%, 16%, and 13% in the gold standard, predicted, and true labels, respectively. The predicted label was not significantly different from the gold standard (p = 0.11) but inferior to the true label (difference in MAE: 3.03%). The amount of pneumothorax in thoracostomy patients was 21.6% in predicted cases and 18.5% in true cases.

Secondary Pneumothorax Induced by a Bronchopleural Fistula in a Patient With COVID-19 Pneumonia

COVID-19 is a multi-system disease caused by severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2). One of the main highlights of the disease is the development of pneumonia complicated by adult respiratory distress syndrome. While spontaneous pneumothorax has been reported in some patients with COVID-19, bronchopleural fistula has seldom been reported as the primary cause in these cases. We describe the rare case of a young patient who developed a pneumothorax complicating COVID-19 and was found to have a bronchopleural fistula and empyema secondary to Staphylococcus aureus superinfection.

A case report of secondary spontaneous pneumothorax in acute exacerbation of COPD managed with improvised chest tube drain

Introduction

and importance: We reported a case of secondary spontaneous pneumothorax (SSP) in a 70-years-old male with acute exacerbation of COPD (AE COPD) managed with improvised chest tube drain (ICD).

Case presentation

He presented with sudden onset breathlessness and oxygen saturation of 78%. With prolonged expiration on auscultation, he was treated as AE COPD with oxygen therapy, nebulization with albuterol/ipratropium, and injectable antibiotics and steroids. The patient was not improving with treatment on third day, and non-critical respiratory distress continued. Considering the alternative diagnosis, the chest X-ray was done which revealed right sided spontaneous pneumothorax and COPD. Due to his reluctancy to go to higher center for chest tube insertion during ongoing COVID-19 pandemic, we inserted ICD (intravenous set put in saline bottle) at our primary care. Following drainage, breathlessness improved and saturation increased. Then inpatient symptomatic treatment for COPD was continued for three more days. He was discharged on inhalers after fifth day and asked for follow up after 10 days. He came after 1 month and on repeat chest X-ray, his right sided pneumothorax resolved completely and COPD was in control with inhaled medications. There was no recurrence of pneumothorax in five months follow up.

Clinical discussion

ICD is a safe, and an alternative option in resource limited setting. However, the guidelines recommend chest tube insertion as appropriate treatment.

Conclusion

This would remind the physicians to anticipate the alternative possibility, and to re-examine those with AE COPD who are not improving as expected with oxygen and nebulization therapy.

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High level of clinical acumen is required to early anticipate the spontaneous pneumothorax in acute exacerbation of COPD.

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We should be vigilant and re-examine the cases of acute exacerbation of COPD, not improving with oxygen and nebulization.

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Improvised chest drain is an alternative option for treating secondary spontaneous pneumothorax.

Acute Respiratory Failure

Respiratory failure is one of the most common reasons for hospitalization and intensive care unit (ICU) admissions, and a diverse range of etiologies can precipitate it. Respiratory failure can result from various mechanisms such as hypoventilation, diffusion impairment, shunting, ventilation-perfusion mismatch, or a combination of those mentioned earlier. Hence, an accurate understanding of different pathophysiologic mechanisms is required for appropriate patient care. Prompt identification and treatment of various respiratory emergencies such as tension pneumothorax, massive hemoptysis, and high-risk pulmonary embolism lead to fewer complications, shorter ICU and hospital stay, and improved survival. This review article entails common respiratory failure pathologies encountered in the ICU and addresses their epidemiology, pathophysiology, clinical presentation, and management.

Correlative analysis of lung CT findings in patients with Birt–Hogg–Dubé Syndrome and the occurrence of spontaneous pneumothorax: a preliminary study

Background

The diagnosis of patients with Birt–Hogg–Dubé (BHD) syndrome is always delayed (even for more than 10 years). Improving the understanding and diagnosis of this disease is vital for clinicians and radiologists. In this study we presented the chest computed tomography (CT) findings of BHD syndrome and offered suggestions for BHD cases with spontaneous pneumothorax.

Methods

Twenty-six BHD patients from 11 families (10 men, 16 women; mean age: 46 ± 12 years, 20–68 years) were included. The clinical features of the patients included pneumothorax, renal lesions, and skin lesions. Twenty-three patients underwent chest CT imaging. The cyst condition of each patient derived from reconstructed chest CT imaging was recorded, including the cyst number, size, volume, pattern, and distribution.

Results

Pneumothorax occurred in 54% (14/26) of patients. Among them, 43% (6/14) had pneumothorax more than twice. However, typical skin and renal lesions were absent. Four patients had renal hamartoma. CT showed that 23 (100%) patients had lung cysts. Pulmonary cysts were bilateral and multiple, round, irregular, or willow-like. And 93.6% of the large cysts (long-axis diameter ≥ 20 mm) were under the pleura, and near the mediastinum and spine. The long-axis diameter, short-axis diameter and volume of the largest cysts were associated with the occurrence of pneumothorax (all P < 0.05).

Conclusions

Chest CT imaging can reveal some characteristic features of BHD syndrome. The occurrence of pneumothorax in BHD patients is closely related to their pulmonary cystic lesions.

The Collateral Damage of the Pandemic on Non-COVID Related Pneumothorax Patients: A Retrospective Cohort Study

Background: Since the onset of the COVID-19 pandemic, there have been many reported cases showing the consequences—or the collateral damages—of COVID-19 on patients with non-COVID-related diseases. This study aimed to compare the clinical manifestations and treatment results of non-COVID-related pneumothorax patients before and during the pandemic. Methods: We retrospectively reviewed non-COVID-related pneumothorax patients who visited our hospital before the onset of the pandemic and during the pandemic. The primary outcome was the difference in the amount of pneumothorax between the two periods, and the secondary outcome was the difference in the treatment results between them. Multivariable logistic regression was conducted to find risk factors related to massive pneumothorax. Results: There were 122 and 88 patients in the pre-pandemic and pandemic groups, respectively. There was no significant difference between the two groups with respect to the preoperative demographic variables. However, the median amount of pneumothorax was significantly higher in the pandemic group (pre-pandemic: 34.75% [interquartile range (IQR) 18.30–62.95] vs. pandemic: 53.55% [IQR 33.58–88.80], p < 0.0001) and massive pneumothorax were more frequent in the pandemic group (52.3% vs. 30.3%, p = 0.002). Furthermore, more patients experienced re-expansion pulmonary edema after treatments during the pandemic (p = 0.0366). In multivariable analysis, the pandemic (OR: 2.70 [95% CI 1.49–4.90], p = 0.0011) was related to the occurrence of massive pneumothorax. Conclusion: During the pandemic, patients presented with a larger size of pneumothorax and had more re-expansion pulmonary edema, even in a country that handled the COVID-19 pandemic relatively well.

Management of primary spontaneous pneumothorax: Our single-center, five-year experience

BACKGROUND

In this study, we aimed to analyze the effects of admission time to the hospital and different variables on the treatment efficiency and to evaluate the recurrence during the clinical management process in patients with the diagnosis of primary spontaneous pneumothorax.

METHODS

A total of 149 patients with primary spontaneous pneumothorax (131 males, 18 females; mean age: 24.8±6.8 years; range, 17 to 35 years) treated in our clinic between January 2015 and December 2019 were retrospectively analyzed. Time from symptom onset to hospital admission (admission time) was classified as three periods: <24 h, between 24 and 72 h, and >72 h. Data including admission time, demographic and clinical characteristics, smoking history, body mass index, the use of pleurectomy or pleural abrasion during surgery were collected from the charts of the patients.

RESULTS

Admission time had no statistically significant effect on the length of hospital stay, recurrence, and the need for surgery. Male sex, smoking history, and lower body mass index had no significant effect on the recurrence. Recurrence and length of hospital stay did not significantly differ between the patients in whom pleurectomy or pleural abrasion added to the procedure during the operation.

CONCLUSION

A longer interval between symptom onset and hospital admission and lower body mass index have no adverse effect on treatment outcomes and the recurrence in patients with primary spontaneous pneumothorax. Despite the fact that surgical treatment significantly decreases the recurrence rate, pleurectomy and pleural abrasion techniques have no significant difference on the clinical influence and recurrence of these patients.

Pneumothorax: Classification and Etiology

Pneumothorax is a common problem worldwide. Pneumothorax develops secondary to diverse aetiologies; in many cases, there may be no recognizable lung abnormality. The pathogenetic mechanism(s) causing spontaneous pneumothorax may be related to an interplay between lung-related abnormalities and environmental factors such as smoking. Tobacco smoking is a major risk factor for primary spontaneous pneumothorax; chronic obstructive pulmonary disease is most frequently associated with secondary spontaneous pneumothorax. This review article provides an overview of the historical perspective, epidemiology, classification, and aetiology of pneumothorax. It also aims to highlight current knowledge and understanding of underlying risks and pathophysiological mechanisms in pneumothorax development.

Bronchopleural fistula causing persistent pneumothorax in COVID-19 pneumonia patient with no risk factors

Although pneumothorax is a well-known complication of COVID-19 pneumonia especially in patients requiring mechanical ventilation, bronchopleural fistula causing persistent pneumothorax in sole COVID-19 pneumonia is extremely rare. In this case, we illustrate that bronchopleural fistula can be found in COVID-19 pneumonia, even with no risk factors nor mechanical ventilation administration.

Point of care echocardiography and lung ultrasound in critically ill patients with COVID-19

Hundreds of millions got infected, and millions have died worldwide and still the number of cases is rising.

Chest radiographs and computed tomography (CT) are useful for imaging the lung but their use in infectious diseases is limited due to hygiene and availability.

Lung ultrasound has been shown to be useful in the context of the pandemic, providing clinicians with valuable insights and helping identify complications such as pleural effusion in heart failure or bacterial superinfections. Moreover, lung ultrasound is useful for identifying possible complications of procedures, in particular, pneumothorax.

Associations between coronavirus disease 2019 (COVID-19) and cardiac complications, such as acute myocardial infarction and myocarditis, have been reported. As such, point of care echocardiography as well as a comprehensive approach in later stages of the disease provide important information for optimally diagnosing and treating complications of COVID-19.

In our experience, lung ultrasound in combination with echocardiography, has a great impact on treatment decisions. In the acute state as well as in the follow-up setting after a severe or critical state of COVID-19, ultrasound can be of great impact to monitor the progression and regression of disease.

Risk of pneumothorax in pneumoconiosis patients in Taiwan: a retrospective cohort study

OBJECTIVES

This study was conducted to explore the association between pneumoconiosis and pneumothorax.

DESIGN

Retrospective cohort study.

SETTING

Nationwide population-based study using the Taiwan National Health Insurance Database.

PARTICIPANTS

A total of 2333 pneumoconiosis patients were identified (1935 patients for propensity score (PS)-matched cohort) and matched to 23 330 control subjects by age and sex (7740 subjects for PS-matched cohort).

PRIMARY AND SECONDARY OUTCOME MEASURES

The incidence and the cumulative incidence of pneumothorax.

RESULTS

Both incidence and the cumulative incidence of pneumothorax were significantly higher in the pneumoconiosis patients as compared with the control subjects (p<0.0001). For multivariable Cox regression analysis adjusted for age, sex, residency, income level and other comorbidities, patients with pneumoconiosis exhibited a significantly higher risk of pneumothorax than those without pneumoconiosis (HR 3.05, 95% CI 2.18 to 4.28, p<0.0001). The male sex, heart disease, peripheral vascular disease, chronic pulmonary disease and connective tissue disease were risk factors for developing pneumothorax in pneumoconiosis patients.

CONCLUSIONS

Our study revealed a higher risk of pneumothorax in pneumoconiosis patients and suggested potential risk factors in these patients. Clinicians should be aware about the risk of pneumothorax in pneumoconiosis patients.

Pleurodesis After Bronchial Occlusion for Inoperable Secondary Spontaneous Pneumothorax

BACKGROUND

In many cases of secondary spontaneous pneumothorax (SSP), surgery is not feasible. Furthermore, in cases with a collapsed lung or numerous air leaks, pleurodesis is ineffective, and treatment options are severely limited. For these cases, bronchial occlusion might be the only effective treatment, despite the low success rate. If, however, bronchial occlusion can expand the lung and reduce air leakage, it can positively amplify later effects on pleurodesis, resulting in a powerful treatment. We reviewed the clinical data of patients who underwent bronchial occlusion with endobronchial Watanabe spigot (BO-EWS) and pleurodesis to investigate the usefulness of bronchial occlusion therapy in inoperable SSP patients.

MATERIALS AND METHODS

This single-center, retrospective study reviewed 36 cases of inoperable SSP patients who underwent pleurodesis after BO-EWS from April 2007 to October 2018. Twenty cases were allocated to the air leak analysis group, and 16 cases were included in the pneumothorax volume analysis group. The Robert David Cerfolio classification and the Collins method were used to evaluate air leak and pneumothorax volume, respectively.

RESULTS

Pneumothorax volumes decreased significantly after BO-EWS from 29.1%±17.3% to 12.1%±8.8%, while the air leak score decreased from 2.9±1.4 to 1.2±1.0. The success rate for chest tube removals in cases that underwent pleurodesis after BO-EWS was 85.0% (17/20).

CONCLUSIONS

This study demonstrated the synergistic effectiveness of BO-EWS and the usefulness of pleurodesis treatment in inoperable SSP patients with lung collapse or numerous air leaks. We believe that this treatment will benefit patients with inoperable SSP which, until now, has had few treatment options.

Management of complex pleural disease in the critically ill patient

Disorders of the pleural space are quite common in the critically ill patient. They are generally associated with the underlying illness. It is sometimes difficult to assess for pleural space disorders in the ICU given the instability of some patients. Although the portable chest X-ray remains the primary modality of diagnosis for pleural disorders in the ICU. It can be nonspecific and may miss subtle findings. Ultrasound has become a useful tool to the bedside clinician to aid in diagnosis and management of pleural disease. The majority of pleural space disorders resolve as the patient’s illness improves. There remain a few pleural processes that need specific therapies. While uncomplicated parapneumonic effusions do not have their own treatments. Those that progress to become a complex infected pleural space can have its individual complexity in therapy. Chest tube drainage remains the cornerstone in therapy. The use of intrapleural fibrinolytics has decreased the need for surgical referral. A large hemothorax or pneumothorax in patients admitted to the ICU represent medical emergencies and require emergent action. In this review we focus on the management of commonly encountered complex pleural space disorders in critically ill patients such as complicated pleural space infections, hemothoraces and pneumothoraces.

Pneumothorax in patients with respiratory failure in ICU

Pneumothorax is not an uncommon occurrence in ICU patients. Barotrauma and iatrogenesis remain the most common causes for pneumothorax in critically ill patients. Patients with underlying lung disease are more prone to develop pneumothorax, especially if they require positive pressure ventilation. A timely diagnosis of pneumothorax is critical as it may evolve into tension physiology. Most occurrences of pneumothoraces are readily diagnosed with a chest X-ray. Tension pneumothorax is a medical emergency, and managed with immediate needle decompression followed by tube thoracostomy. A computed tomography (CT) scan of the chest remains the gold standard for diagnosis; however, getting a CT scan of the chest in a critically ill patient can be challenging. The use of thoracic ultrasound has been emerging and is proven to be superior to chest X-ray in making a diagnosis. The possibility of occult pneumothorax in patients with thoracoabdominal blunt trauma should be kept in mind. Patients with pneumothorax in the ICU should be managed with a tube thoracostomy if they are symptomatic or on mechanical ventilation. The current guidelines recommend a small-bore chest tube as the first line management of pneumothorax. In patients with persistent air leak or whose lungs do not re-expand, a thoracic surgery consultation is recommended. In non-surgical candidates, bronchoscopic interventions or autologous blood patch are other options.

Bilateral primary spontaneous pneumothorax with multiple bleb performed by VATS and wedge resection: A rare case in Indonesian adult and review article

Background

Bilateral primary spontaneous pneumothorax (PSP) is a rare case of lung disease.

Case presentation

A 20-year-old man with a complaint of shortness of breath is suspected of having PSP and tuberculosis. The patient underwent water seal drainage installation in both lung cavities, but showed no improvement. Multiple blebs were found after a few days. A wedge resection with VATS became an option. The patient had improved lung function after the procedure.

Discussion

The WSD installation showed lungs improvement. However, when trained for lung expansion, the lung condition became bad. After wedge resection with the help of VATS on multiple blebs, the lung had a significant improvement.

Conclusion

Wedge resection could be considered in PSP patients with multiple blebs.

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The prevalence of bilateral primary spontaneous pneumothorax (PSP) is very low, around 1–2%.

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Multiple blebs in bilateral PSP patients indicate the need for surgery.

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PSP is often found in young adults.

Oxygen saturation associated with recurrent primary spontaneous pneumothorax treated with an intercostal chest drainage

BACKGROUND

Primary spontaneous pneumothorax (PSP) is a condition that may lead to acute chest pain or dyspnea on exertion. Treatment with an intercostal chest drainage (ICD) is warranted. There is limited data on risk factors of recurrent PSP in patients treated with the ICD alone. This study aimed to evaluate risk factors of recurrent PSP in patients with PSP and treated with the ICD.

METHODS

This was a retrospective study and enrolled patients diagnosed as PSP and treated with an ICD. Eligible patients were divided into two groups by evidence of recurrent PSP. Baseline characteristics, physical signs, laboratory results, and duration of ICD treatment were studied and recorded from medical charts. Factors associated with recurrent PSP were computed by using multivariate logistic regression analysis.

RESULTS

There were 80 patients met the study criteria. Of those, 21 patients (26.3%) had recurrent PSP. Of those, 21 patients (26.3%) had recurrent PSP. There were eight factors in the final model for recurrent PSP. Only oxygen saturation at the time of diagnosis was independently associated with recurrent PSP. The adjusted odds ratio (95% confident interval) was 0.57 (0.34, 0.96). A cut point of 96% of oxygen saturation gave sensitivity of recurrent PSP of 80.95%.

CONCLUSION

The prevalence of recurrent PSP was 26.3% in patients with PSP and treated with the ICD. Initial oxygen saturation may be an indicator for recurrent PSP.

Chest X-ray pneumothorax segmentation using U-Net with EfficientNet and ResNet architectures

Medical imaging refers to visualization techniques to provide valuable information about the internal structures of the human body for clinical applications, diagnosis, treatment, and scientific research. Segmentation is one of the primary methods for analyzing and processing medical images, which helps doctors diagnose accurately by providing detailed information on the body's required part. However, segmenting medical images faces several challenges, such as requiring trained medical experts and being time-consuming and error-prone. Thus, it appears necessary for an automatic medical image segmentation system. Deep learning algorithms have recently shown outstanding performance for segmentation tasks, especially semantic segmentation networks that provide pixel-level image understanding. By introducing the first fully convolutional network (FCN) for semantic image segmentation, several segmentation networks have been proposed on its basis. One of the state-of-the-art convolutional networks in the medical image field is U-Net. This paper presents a novel end-to-end semantic segmentation model, named Ens4B-UNet, for medical images that ensembles four U-Net architectures with pre-trained backbone networks. Ens4B-UNet utilizes U-Net's success with several significant improvements by adapting powerful and robust convolutional neural networks (CNNs) as backbones for U-Nets encoders and using the nearest-neighbor up-sampling in the decoders. Ens4B-UNet is designed based on the weighted average ensemble of four encoder-decoder segmentation models. The backbone networks of all ensembled models are pre-trained on the ImageNet dataset to exploit the benefit of transfer learning. For improving our models, we apply several techniques for training and predicting, including stochastic weight averaging (SWA), data augmentation, test-time augmentation (TTA), and different types of optimal thresholds. We evaluate and test our models on the 2019 Pneumothorax Challenge dataset, which contains 12,047 training images with 12,954 masks and 3,205 test images. Our proposed segmentation network achieves a 0.8608 mean Dice similarity coefficient (DSC) on the test set, which is among the top one-percent systems in the Kaggle competition.

Delayed Pneumothorax Post Transbronchial Biopsy: A Case Report

Bronchoscopy is a common and safe procedure with low mortality rates and complications. The risk of pneumothorax (PTX) post bronchoscopy is estimated to be 0.1% but increases to 1-6% with the addition of transbronchial lung biopsy (TBB) to the procedure. Studies have shown that a short observation period is adequate after TBB, and the usual practice is to perform a portable chest radiograph (CXR) to rule out PTX. Delayed PTX is a rare complication post-TBB and very few cases have been reported in the literature. In this report, we discuss a patient with delayed PTX 48 hours post-TBB. A 71-year-old male with a history of malignancy of unknown primary with metastasis to the sacrum and vertebral column presented with lower limb weakness status post-palliative radiation to the spine. His sacral lesion biopsy was inconclusive. He was currently on oral steroids. He was noted to have a left upper lobe lung nodule on a CT scan of the chest. He underwent bronchoscopy with TBB to determine if it was a primary lung malignancy. He was stable post-procedure with an unremarkable CXR for PTX and was discharged with outpatient follow-up. Two days later, he presented to the emergency department with shortness of breath and hypoxemia. A CXR was performed, which showed a left-sided PTX. A chest tube was placed, and a follow-up CXR showed lung immediate re-expansion. The chest tube was removed after two days and the patient was discharged home after a total of four days of hospitalization. Iatrogenic PTX can be due to diagnostic and/or therapeutic interventions. PTX after procedures can be classified as acute (one to four hours post-procedure) or delayed (>4 hours post-procedure). It is recommended to have a CXR within an hour post-TBB. To our knowledge, very few cases of delayed PTX post-TBB have been reported, mostly among lung transplant patients and those with chronic infections such as tuberculosis. In prior reports, it has been speculated that a visceral pleural defect might occur during a biopsy, but is protected by blood clot formation in the proximal bronchus. A PTX then occurs after fibrinolysis of the blood clot. Low immunity and poor wound healing due to chronic inflammation or steroid use can play a role in causing a delayed PTX. Also, the use of pain drugs such as opioids is associated with iatrogenic PTX. Patients with underlying lung disease such as emphysema are more prone to developing a PTX. Another hypothesis is that a tissue flap is created after the biopsy, which obstructs the airflow during exhalation, thereby resulting in a PTX. On the other hand, it is known that lung malignancies, either primary or metastatic, can increase the risk of secondary PTX. In our case, the temporal relationship of the delayed PTX with bronchoscopy makes it more likely that it was related to the lung biopsy (in our case, poorly differentiated non-small cell carcinoma). The underlying malignancy with low immunity, chronic tissue inflammation, and current steroid use may have resulted in delayed lung healing at the biopsy site. This case report highlights the importance of considering delayed PTX among high-risk patients who undergo such procedures. Delayed PTX is a rare complication post-TBB and should be considered in patients who are stable post-procedure but present with dyspnea and/or hypoxemia even days after the procedure.

Pneumothorax Induced by Computed Tomography Guided Transthoracic Needle Biopsy: A Review for the Clinician

Percutaneous computed tomography (CT)-guided transthoracic needle biopsy (TTNB) is a valuable procedure for obtaining tissue or cells for diagnosis, which is especially indispensable in thoracic oncology. Pneumothorax and hemoptysis are the most common complications of percutaneous needle biopsy of the lung. According to reports published over the past decades, pneumothorax incidence in patients who underwent TTNB greatly varies. The morbidity of pneumothorax after CT-guided TTNB depends on several factors, including size and depth of lesions, emphysema, the number of pleural surfaces and fissure crossed, etc. Attention to biopsy planning and technique and post-biopsy precautions help to prevent or minimize potential complications. Many measures can be taken to help prevent the progression of a pneumothorax, which in turn might reduce the number of pneumothoraces requiring chest tube placement. A multitude of therapeutic options is available for the treatment of pneumothorax, varying from observation and oxygen treatment, simple manual aspiration, to chest tube placement. When a pneumothorax develops during the biopsy procedure, it can be manually aspirated after the needle is retracted back into the pleural space or by inserting a separate needle into the pleural space. Biopsy side down positioning of the patient after biopsy significantly reduces the incidence of pneumothorax and the requirement of chest tube placement. Aspiration in biopsy side down position is also recommended for treating pneumothorax when simple manual aspiration is unsuccessful or delayed pneumothorax occurred. Chest tube placement is an important treatment strategy for patients with a large or symptomatic pneumothorax. Clinicians are encouraged to understand the development, prevention, and treatment of pneumothorax. Efforts should be made to reduce the incidence of pneumothorax in biopsy planning and post-biopsy precautions. When pneumothorax occurs, appropriate treatment should be adopted to reduce the risk of worsening pneumothorax.

Electrocardiographic manifestations in a large right-sided pneumothorax

Background

Pneumothorax is an extrapulmonary air accumulation within the pleural space between the lung and chest wall. Once pneumothorax acquires tension physiology, it turns into a potentially lethal condition requiring prompt surgical intervention. Common symptoms are chest pain and dyspnea; hence an electrocardiogram (ECG) is often performed in emergent settings. However, early diagnosis of pneumothorax remains challenging since chest pain and dyspnea are common symptomatology in various life-threatening emergencies, often leading to overlooked or delayed diagnosis. While the majority of left-sided pneumothorax-related ECG abnormalities have been reported, right-sided pneumothorax-related ECG abnormalities remain elucidated.

Case presentation

A 51-year-old man presented to the emergency department with acute-onset chest pain and dyspnea. Upon initial examination, the patient had a blood pressure of 98/68 mmHg, tachycardia of 100 beats/min, tachypnea of 28 breaths/min, and oxygen saturation of 94% on ambient air. Chest auscultation revealed decreased breath sounds on the right side. ECG revealed sinus tachycardia, phasic voltage variation of QRS complexes in V4–6, P-pulmonale, and vertical P-wave axis. Chest radiographs and computed tomography (CT) scans confirmed a large right-sided pneumothorax. The patient’s symptoms, all the ECG abnormalities, and increased heart rate on the initial presentation resolved following an emergent tube thoracostomy. Moreover, we found that these ECG abnormalities consisted of two independent factors: respiratory components and the diaphragm level. Besides, CT scans demonstrated the large bullae with a maximum diameter of 46 × 49 mm in the right lung apex. Finally, the patient showed complete recovery with a thoracoscopic bullectomy.

Conclusions

Herein, we describe a case of a large right-sided primary spontaneous pneumothorax with characteristic ECG findings that resolved following re-expansion of the lung. Our case may shed new light on the mechanisms underlying ECG abnormalities associated with a large right-sided pneumothorax. Moreover, ECG manifestations may provide useful information to suspect a large pneumothorax or tension pneumothorax in emergent settings where ECGs are performed on patients with acute chest pain and dyspnea.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12890-021-01470-1.

Tracheal deviation with phrenic nerve palsy after brachial plexus block

We present a case of a woman who received a left single-injection supraclavicular brachial plexus block for analgesia to facilitate upper extremity orthopaedic surgery. Before tracheal extubation she desaturated, was noted to have a low tidal volume and reduced left-sided air entry on auscultation of the chest. A chest x-ray taken 1 h following tracheal extubation revealed elevation of the left hemidiaphragm and a rightward shift of the trachea and mediastinal structures, with no evidence of pneumothorax. Findings were in-keeping with phrenic nerve palsy complicating the brachial plexus block performed. The patient was asymptomatic and discharged home the next day following repeat chest x-rays. We believe this is the first report of tracheal deviation contralateral to the side of an elevated hemidiaphragm secondary to phrenic nerve palsy from a brachial plexus block.

New insights into spontaneous pneumothorax: A review

A spontaneous pneumothorax is a pneumothorax that does not arise from trauma or an iatrogenic cause. Although the traditional classification of either primary or secondary spontaneous pneumothorax based on the absence or presence of overt underlying lung disease is still widely used, it is now well recognised that primary spontaneous pneumothorax is associated with underlying pleuropulmonary disease. Current evidence indicates that computed tomography screening for underlying disease should be considered in patients who present with spontaneous pneumothorax. Recent evidence suggests that conservative management has similar recurrence rates, less complications and shorter hospital stay compared with invasive interventions, even in large primary spontaneous pneumothoraces of >50%. A more conservative approach which is based on clinical assessment rather than pneumothorax size can thus be followed during the acute management in selected stable patients. The purpose of this review is to revisit the aetiology of spontaneous pneumothorax, identify which patients should be investigated for secondary causes and to give an overview of the management strategies at initial presentation as well as secondary prevention.

Cracking the Opium Den: Cardiothoracic Manifestations of Drug Abuse

Recreational drug use is increasing worldwide, with emergency room visits and total deaths from drug overdose rising in recent years. Complications from prescription and recreational drug use may result from the biochemical effects of the drugs themselves, impurities mixed with substances, or from causes related to the method of drug administration. The presentation of drug overdose may be complex due to multisubstance abuse, including cigarette smoking and alcoholism, and can impact any organ system. Patients may present without history, and radiologists may be the first clinicians to suggest the diagnosis. We aim to explore the cardiothoracic manifestations of drug abuse and their multimodality imaging manifestations.

Primary spontaneous pneumothorax in children: A single institutional experience

BACKGROUND

The treatment of primary spontaneous pneumothorax (PSP) remains controversial. We aimed to examine the role of chest computed tomography (CT), the advantages of pigtail catheter versus chest tube regarding duration of drainage or hospitalization period, and the impact of small PSP and surgical treatment on recurrence rate.

METHODS

We retrospectively reviewed the medical records of 109 children with PSP (20 years' period). Patients with recurrent and those with non-recurrent PSP were compared.

RESULTS

We recorded 183 episodes of PSP (45% recurrences), 89 patients (97%) were male, and the median age at presentation was 16 years. There were no significant differences between recurrence and non-recurrence PSP regarding age, gender, medical background, presentation symptoms, type of chest drain, median hospitalization length and median follow-up period. Recurrences were less frequent among patients who presented with small PSP and were treated conservatively (P = 0.029). PSP was almost always unilateral and the recurrence was observed ipsilateral in almost 80% of the cases. CT was more frequently used and blebs/bullae were more frequently found among patients with recurrent PSP. Pigtail use had no advantage in reducing hospitalization period and surgical procedures prevented recurrences.

CONCLUSION

The size of pneumothorax at presentation helps to predict recurrences. There are no differences regarding duration of drainage or hospitalization period in the use of pigtail compared to chest tube. CT helps evaluate findings in the lungs in recurrent cases of PSP and surgery prevents recurrences effectively.

Polymeric Tissue Adhesives

Polymeric tissue adhesives provide versatile materials for wound management and are widely used in a variety of medical settings ranging from minor to life-threatening tissue injuries. Compared to the traditional methods of wound closure (i.e., suturing and stapling), they are relatively easy to use, enable rapid application, and introduce minimal tissue damage. Furthermore, they can act as hemostats to control bleeding and provide a tissue-healing environment at the wound site. Despite their numerous current applications, tissue adhesives still face several limitations and unresolved challenges (e.g., weak adhesion strength and poor mechanical properties) that limit their use, leaving ample room for future improvements. Successful development of next-generation adhesives will likely require a holistic understanding of the chemical and physical properties of the tissue-adhesive interface, fundamental mechanisms of tissue adhesion, and requirements for specific clinical applications. In this review, we discuss a set of rational guidelines for design of adhesives, recent progress in the field along with examples of commercially available adhesives and those under development, tissue-specific considerations, and finally potential functions for future adhesives. Advances in tissue adhesives will open new avenues for wound care and potentially provide potent therapeutics for various medical applications.

Risk factors related to the recurrence of pneumothorax in patients with emphysema

Background

Pneumothorax refers to the abnormal presence of air in the thoracic cavity. Pulmonary emphysema (PE) is often detected during computed tomography (CT), one of the radiological investigations used to diagnose pneumothorax and devise treatment plans in former or current smokers who present with pneumothorax. However, there are few reports that describe the recurrence rate and risk factors associated with recurrence in patients with PE and pneumothorax.

Methods

This study retrospectively cross-sectional analyzed the medical records of 164 patients diagnosed with their first episode of secondary spontaneous pneumothorax and admitted to a tertiary care hospital, between March 2013 and February 2019. The CT scans of 98 patients revealed PE, and 49 patients of those underwent pulmonary function tests (PFTs) after the resolution of pneumothorax. Risk factors for recurrence were analyzed using Cox proportional hazard regression.

Results

All the subjects were male and former or current smokers, with a median age of 72 years. Thirty-seven (75.5%) patients were treated with tube thoracostomy alone, whereas 12 (24.5%) patients underwent chemical pleurodesis via chest tube or video-assisted thoracoscopic surgery. After recovery from pneumothorax, these patients underwent PFT within a median time period of 5.8 months. Median forced vital capacity and forced expiratory volume in 1 second (FEV₁) were 3.02 L (91% predicted) and 1.58 L (67% predicted), respectively. In the current study, the recurrence rate of pneumothorax was observed to be 30.6%, within a median time period of 12.4 months. In multivariable-adjusted analysis, decreased FEV₁ was observed to be significantly higher in the patients who exhibited recurrence of pneumothorax than in those who did not (adjusted hazard ratio, 0.408; P=0.025).

Conclusions

In patients with PE and pneumothorax, PFT, performed after recovery, could be a useful test for predicting the recurrence of pneumothorax.

Sudden death due to tension pneumothorax associated with pulmonary tuberculosis

A man in his seventies who lived alone was found dead in his home. Postmortem computed tomography (CT) performed prior to autopsy showed right-sided tension pneumothorax. Autopsy revealed an active pulmonary tuberculosis (TB) lesion. Macroscopic and histopathological findings showed pleural infiltration by TB lesions, suggesting that tension pneumothorax developed in association with TB infection. Routine postmortem CT performed prior to autopsy is useful in screening for TB because the presence of TB lesions can be confirmed from characteristic pulmonary findings. However, it may be difficult to identify tuberculous pulmonary lesions on CT if pneumothorax occurs and the lung collapses completely as in this case. Thus, forensic pathologists and radiologists should be cognizant of this rare complication of TB.

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.