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

Complications during Veno-Venous Extracorporeal Membrane Oxygenation in COVID-19 and Non-COVID-19 Patients with Acute Respiratory Distress Syndrome

Background: Acute respiratory distress syndrome (ARDS) presents a significant challenge in critical care settings, characterized by compromised gas exchange, necessitating in the most severe cases interventions such as veno-venous extracorporeal membrane oxygenation (vv-ECMO) when conventional therapies fail. Critically ill ARDS patients on vv-ECMO may experience several complications. Limited data exist comparing complication rates between COVID-19 and non-COVID-19 ARDS patients undergoing vv-ECMO. This retrospective observational study aimed to assess and compare complications in these patient cohorts. Methods: We retrospectively analyzed the medical records of all patients receiving vv-ECMO for ARDS between March 2020 and March 2022. We recorded the baseline characteristics, the disease course and complication (barotrauma, bleeding, thrombosis) before and after ECMO cannulation, and clinical outcomes (mechanical ventilation and ECMO duration, intensive care unit, and hospital lengths of stay and mortalities). Data were compared between COVID-19 and non-COVID-19 patients. In addition, we compared survived and deceased patients. Results: Sixty-four patients were included. COVID-19 patients (n = 25) showed higher rates of pneumothorax (28% vs. 8%, p = 0.039) with subcutaneous emphysema (24% vs. 5%, p = 0.048) and longer non-invasive ventilation duration before vv-ECMO cannulation (2 [1; 4] vs. 0 [0; 1] days, p = <0.001), compared to non-COVID-19 patients (n = 39). However, complication rates and clinical outcomes post-vv-ECMO were similar between groups. Survival analysis revealed no significant differences in pre-vv-ECMO complications, but non-surviving patients had a trend toward higher complication rates and more pleural effusions post-vv-ECMO. Conclusions: COVID-19 patients on vv-ECMO exhibit higher pneumothorax rates with subcutaneous emphysema pre-cannulation; post-cannulation complications are comparable to non-COVID-19 patients.

[Cavitary lung lesions in COVID-19 associated pneumonia: a single-center study of 40 cases]

OBJECTIVE

To demonstrate clinical features and outcomes in patients with cavitary lung lesions and COVID-19 associated pneumonia.

MATERIAL AND METHODS

A retrospective analysis of electronic medical records of 8261 patients with COVID-19 was performed. We selected 40 patients meeting the inclusion criteria. Sex, age, hospital-stay, lung tissue lesion, comorbidities, treatment, methods of respiratory support, complications and outcomes were evaluated.

RESULTS

Cavitary lung lesions were more common in men (67.5%). Age of patients ranged from 28 to 88 (mean 64.9±13.7) years. Hospital-stay in patients with cavitary lung lesions was 9-58 (median 27.5) days. There were 18 complications in 14 (35%) patients. Pneumothorax, isolated pneumomediastinum, pleural empyema, hemoptysis and sigmoid colon perforation were considered as complications of cavitary lung lesions. Nine (22.5%) patients died (5 of them with complications). Three patients died after surgical treatment. Long-term results were analyzed in 8 (25.8%) patients. Patients were followed-up for 3 months after discharge. Shrinkage of lesions occurred after 7-60 (mean 23) days, and complete obliteration of cavities came after 32 (range 14-90) days.

CONCLUSION

Cavitary lung lesions are a rare complication of COVID-19 pneumonia. There was no significant correlation of complications with age, sex, therapy, volume of lung lesions and non-invasive ventilation (NIV). Despite more common fatal outcomes in older patients undergoing NIV, the last one was prescribed exclusively due to disease progression and respiratory failure. Further research on this problem is necessary to identify possible risk factors of cavitary lung lesions.

Determinants of Pneumothorax Among Mechanically Ventilated COVID-19 Intensive Care Unit Patients, a Single Centre Study

Introduction

Millions of deaths and co-morbidities have been brought on by the COVID-19 epidemic worldwide. Acute respiratory distress syndrome (ARDS), multiple organ failure, and death can result from the condition in some people. The disease's course can range from a moderate upper respiratory tract infection to severe pneumonia. Numerous reports have been made on the occurrence of pneumothorax in COVID-19 ICU patients, particularly in those who are receiving invasive ventilation. This study assesses factors associated with pneumothorax among mechanically ventilated COVID-19 ICU patients in Addis Ababa, Ethiopia.

Methods

A case-control study design was employed from August 1, 2022, to August 31, 2022, GC, with a sample size of 281, where cases are 94 and controls are 187. A pre-tested structured quantitative tool was used to collect data on ODK and export it to SPSS version 26 for analysis. Descriptive statistics were presented using text and tables. The association between variables was analyzed with binary logistic regression. A statistical significance was declared at a p-value of 0.05 with a 95% confidence interval. Assumptions like model fitness and multicollinearity were checked to be satisfied.

Results

A total of 281 (94 cases and 187 controls) patient charts were carefully reviewed. After adjustment for possible confounders in multivariate analysis, ARDS (AOR = 0.214, 95% CI (0.088, 0.519), P value =0.001) and invasive ventilation (AOR = 0.311, 95% CI (0.121, 0.796), P value =0.015) had a significant association with pneumothorax.

Conclusion

Despite the introduction of preventive breathing methods, pneumothorax is still a frequent and deadly consequence in COVID-19 patients with ARDS. ARDS and invasive mechanical ventilation were found to be significantly associated with the development of pneumothorax. Health facilities should be well equipped with recent medical equipment in intensive care units and with well-trained and organized manpower.

Ventilatory associated barotrauma in COVID-19 patients: A multicenter observational case control study (COVI-MIX-study)

BACKGROUND

The risk of barotrauma associated with different types of ventilatory support is unclear in COVID-19 patients. The primary aim of this study was to evaluate the effect of the different respiratory support strategies on barotrauma occurrence; we also sought to determine the frequency of barotrauma and the clinical characteristics of the patients who experienced this complication.

METHODS

This multicentre retrospective case-control study from 1 March 2020 to 28 February 2021 included COVID-19 patients who experienced barotrauma during hospital stay. They were matched with controls in a 1:1 ratio for the same admission period in the same ward of treatment. Univariable and multivariable logistic regression (OR) were performed to explore which factors were associated with barotrauma and in-hospital death.

RESULTS

We included 200 cases and 200 controls. Invasive mechanical ventilation was used in 39.3% of patients in the barotrauma group, and in 20.1% of controls (p<0.001). Receiving non-invasive ventilation (C-PAP/PSV) instead of conventional oxygen therapy (COT) increased the risk of barotrauma (OR 5.04, 95% CI 2.30 - 11.08, p<0.001), similarly for invasive mechanical ventilation (OR 6.24, 95% CI 2.86-13.60, p<0.001). High Flow Nasal Oxygen (HFNO), compared with COT, did not significantly increase the risk of barotrauma. Barotrauma frequency occurred in 1.00% [95% CI 0.88-1.16] of patients; these were older (p=0.022) and more frequently immunosuppressed (p=0.013). Barotrauma was shown to be an independent risk for death (OR 5.32, 95% CI 2.82-10.03, p<0.001).

CONCLUSIONS

C-PAP/PSV compared with COT or HFNO increased the risk of barotrauma; otherwise HFNO did not. Barotrauma was recorded in 1.00% of patients, affecting mainly patients with more severe COVID-19 disease. Barotrauma was independently associated with mortality.

TRIAL REGISTRATION

this case-control study was prospectively registered in clinicaltrial.gov as NCT04897152 (on 21 May 2021).

Effects of pulmonary air leak on patients with coronavirus disease 2019 (COVID-19): a systematic review and meta-analysis

BACKGROUND

Coronavirus disease 2019 (COVID-19) has posed increasing challenges to global health systems. We aimed to understand the effects of pulmonary air leak (PAL), including pneumothorax, pneumomediastinum and subcutaneous emphysema, on patients with COVID-19.

METHODS

We searched PubMed, Embase and Web of Science for data and performed a meta-analysis with a random-effects model using Stata 14.0. This meta-analysis was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.

RESULTS

Thirty-five articles were included in the meta-analysis. The data came from 14 countries and included 3,047 COVID-19 patients with PAL, 11,3679 COVID-19 patients without PAL and 361 non-COVID-19 patients with PAL. We found that the incidence of PAL was much higher in COVID-19 patients than in non-COVID-19 patients (odds ratio (OR) = 6.13, 95% CI: 2.09-18.00). We found that the group of COVID-19 patients with PAL had a longer hospital stay (standardized mean difference (SMD) = 0.79, 95% CI: 0.27-1.30) and intensive care unit (ICU) stay (SMD = 0.51, 95% CI: 0.19-0.83) and comprised more ICU (OR = 15.16, 95% CI: 6.51-35.29) and mechanical ventilation patients (OR = 5.52, 95% CI: 1.69-17.99); furthermore, the mortality rate was also higher (OR = 2.62, 95% CI: 1.80-3.82).

CONCLUSIONS

Patients with lung injuries caused by COVID-19 may develop PAL. COVID-19 patients with PAL require more medical resources, have more serious conditions and have worse clinical outcomes.

PROSPERO REGISTRATION NUMBER

CRD42022365047.

Non-Ventilated Patients with Spontaneous Pneumothorax or Pneumomediastinum Associated with COVID-19: Three-Year Debriefing across Five Pandemic Waves

Spontaneous pneumothorax and pneumomediastinum (SP-SPM) are relatively rare medical conditions that can occur with or independently of COVID-19. We conducted a retrospective analysis of SP-SPM cases presented to the emergency departments (EDs) of two University-affiliated tertiary hospitals from 1 March 2020 to 31 October 2022. A total of 190 patients were identified: 52 were COVID-19 cases, and 138 were non-COVID-19 cases. The primary outcome we were looking for was in-hospital mortality. The secondary outcomes concerned the disease severity assessed by (a) days of hospitalization; (b) required mechanical ventilation (MV); and (c) required intensive care (IC). All were investigated in the context of the five pandemic waves and the patients' age and comorbidities. The pandemic waves had no significant effect on the outcomes of these patients. Logistic regression found age (OR = 1.043; 95%CI 1.002-1.085), COVID-19 (OR = 6.032; 95%CI 1.757-20.712), number of comorbidities (OR = 1.772; 95%CI 1.046-3.001), and ground-glass opacities over 50% (OR = 5.694; 95%CI 1.169-27.746) as significant risk predictors of in-hospital death while controlling for gender, smoking, the pandemic wave, and the extension of SP-SPM. The model proved good prediction performance (Nagelkerke R-square = 0.524) and would hold the same significant predictors for MV and IC.

COVID-19-associated lung weakness (CALW): Systematic review and meta-analysis

OBJECTIVES

To assess mortality and different clinical factors derived from the development of atraumatic pneumothorax (PNX) and/or pneumomediastinum (PNMD) in critically ill patients as a consequence of COVID-19-associated lung weakness (CALW).

DESIGN

Systematic review with meta-analysis.

SETTING

Intensive Care Unit (ICU).

PARTICIPANTS

Original research evaluating patients, with or without the need for protective invasive mechanical ventilation (IMV), with a diagnosis of COVID-19, who developed atraumatic PNX or PNMD on admission or during hospital stay.

INTERVENTIONS

Data of interest were obtained from each article and analyzed and assessed by the Newcastle-Ottawa Scale. The risk of the variables of interest was assessed with data derived from studies including patients who developed atraumatic PNX or PNMD.

MAIN VARIABLES OF INTEREST

Mortality, mean ICU stay and mean PaO2/FiO2 at diagnosis.

RESULTS

Information was collected from 12 longitudinal studies. Data from a total of 4901 patients were included in the meta-analysis. A total of 1629 patients had an episode of atraumatic PNX and 253 patients had an episode of atraumatic PNMD. Despite the finding of significantly strong associations, the great heterogeneity between studies implies that the interpretation of results should be made with caution.

CONCLUSIONS

Mortality among COVID-19 patients was higher in those who developed atraumatic PNX and/or PNMD compared to those who did not. The mean PaO2/FiO2 index was lower in patients who developed atraumatic PNX and/or PNMD. We propose grouping these cases under the term COVID-19-associated lung weakness (CALW).

Pneumothorax in Acute Neurologically Ill COVID-19 Positive Patients: A Brief Report

Background

Pneumothorax is reported as a complication of coronavirus disease-2019 (COVID-19). The present report describes the incidence, clinical characteristics, and outcomes of pneumothorax in acute neurologically ill COVID-19 positive patients admitted to the COVID-19 neuro-intensive care unit (CNICU).

Methods

In this retrospective study, pneumothorax was identified by reviewing chest radiographs of acute neurologically ill patients with and without associated COVID-19 admitted to the CNICU and non-COVID-19 NICU, respectively, from July to November 2020. The clinico-epidemiological characteristics of acute neurologically ill COVID-19 positive patients with pneumothorax are described.

Results

The incidence of pneumothorax was 17% (8/47) in acute neurologically ill COVID-19 positive patients in the CNICU and 14.6% (6/41) in patients who received mechanical ventilation (MV). In contrast, the incidence of pneumothorax in acute neurologically ill non-COVID-19 patients admitted to the NICU was 3.7% (7/188) and 0.69% (1/143) in patients receiving MV.

Conclusion

In our study, the incidence of pneumothorax was higher in patients with concomitant neurological and COVID-19 diseases than in acute neurologically ill non-COVID-19 patients managed during the same period in the ICUs.

COVID-19-Related Pleural Diseases

Coronavirus disease 2019 (COVID-19)-related pleural diseases are now well recognized. Since the beginning of the pandemic, increasing cases of pleural diseases including pneumothorax, pneumomediastinum, and pleural effusion with severe COVID-19 infection have attracted the attention of physicians and are not incidental or due to barotrauma. The complicated course of COVID-19 illness highlights the complex pathophysiological underpinnings of pleural complications. The management of patients with pneumothorax and pneumomediastinum is challenging as the majority require assisted ventilation; physicians therefore appear to have a low threshold to intervene. Conversely, pleural effusion cases, although sharing some similar patient characteristics with pneumothorax and pneumomediastinum, are in general managed more conservatively. The evidence suggests that patients with COVID-19-related pleural diseases, either due to air leak or effusion, have more severe disease with a worse prognosis. This implies that prompt recognition of these complications and targeted management are key to improve outcomes.

The prognostic effect of concomitant COVID-19 with spontaneous pneumothorax

Background

The aim of this study was to investigate the prevalence of novel coronavirus disease 2019 (COVID-19) in patients hospitalized with primary spontaneous pneumothorax and to evaluate its possible effects on the clinical course, treatment, and the prognosis.

Methods

Between April 2020 and January 2021, a total of 86 patients (78 males, 8 females; mean age: 27±5 years; range, 16 to 40 years) who had no underlying lung disease and were diagnosed with the first episode of spontaneous pneumothorax were retrospectively analyzed. At the same time of diagnosis, all patients were screened for COVID-19 via polymerase chain reaction test of nasopharyngeal swabs. According to the test results, the patients were divided into two groups as COVID-19(+) and COVID-19(-). The duration of air leak, hospital stay, recurrence rates and treatment modalities, and mortality rates of the two groups were compared.

Results

Following a pneumothorax diagnosis, 18 (21%) patients were diagnosed with COVID-19. In COVID-19(+) patients, the mean air leak and lung expansion duration were significantly longer (p<0.0001 for both). In these patients, the mean length of hospital stay was also significantly longer (p<0.0001). During the median follow-up of six months, no mortality was observed and the recurrence rate was similar between the two groups (p=0.998).

Conclusion

Our study results suggest that COVID-19 negatively affects the recovery time in patients with spontaneous pneumothorax.

Pneumothorax, pneumomediastinum, and subcutaneous emphysema in hospitalized COVID-19 patients: incidence, clinical characteristics, and outcomes

BACKGROUND

Limited data is available on the incidence and outcomes of pneumothorax (PTX), pneumomediastinum (PNM), and subcutaneous emphysema (SCE) in COVID-19 patients. This study aimed to investigate the characteristics of these complications in hospitalized COVID-19 patients.

RESEARCH DESIGN AND METHODS

A retrospective study was conducted, involving adult COVID-19 patients admitted to Mayo Clinic Florida from 03/2020-06/2022. Patients were divided into two groups based on the presence or absence of PTX/PNM/SCE.

RESULTS

1926 hospitalized patients with COVID-19 were included, of which 518 were admitted to the ICU. The incidence of PTX/PNM/SCE was 6.3%. Patients with these complications were more likely to be male, Asian, and unvaccinated. Conversely, they were less likely to have chronic obstructive pulmonary disease. Patients who developed PTX/PNM/SCE after 72 hours of admission were more likely to receive high-dose corticosteroids and for an extended duration. The affected group had an adjusted odds ratio for in-hospital mortality of 13.32 (95%CI, 8.19-21.59) and ICU admission of 9.14 (95%CI, 5.3-12.78) compared to the unaffected group.

CONCLUSION

Although the occurrence of PTX/PNM/SCE in hospitalized COVID-19 patients was rare, it was associated with worse outcomes. Corticosteroids may contribute to the pathogenesis of these complications; however, further studies are needed to investigate this relationship in more detail.

The Macklin effect closely correlates with pneumomediastinum in acutely ill intubated patients with COVID-19 infection

PURPOSE

Patients with COVID-19 infection are frequently found to have pulmonary barotrauma. Recent work has identified the Macklin effect as a radiographic sign that often occurs in patients with COVID-19 and may correlate with barotrauma.

METHODS

We evaluated chest CT scans in COVID-19 positive mechanically ventilated patients for the Macklin effect and any type of pulmonary barotrauma. Patient charts were reviewed to identify demographic and clinical characteristics.

RESULTS

The Macklin effect on chest CT scan was identified in a total of 10/75 (13.3%) COVID-19 positive mechanically ventilated patients; 9 developed barotrauma. Patients with the Macklin effect on chest CT scan had a 90% rate of pneumomediastinum (p < 0.001) and a trend toward a higher rate of pneumothorax (60%, p = 0.09). Pneumothorax was most frequently omolateral to the site of the Macklin effect (83.3%).

CONCLUSION

The Macklin effect may be a strong radiographic biomarker for pulmonary barotrauma, most strongly correlating with pneumomediastinum. Studies in ARDS patients without COVID-19 are needed to validate this sign in a broader population. If validated in a broad population, future critical care treatment algorithms may include the Macklin sign for clinical decision making and prognostication.

[COVID-19-associated lung weakness (CALW): Systematic review and meta-analysis]

Objectives

To assess mortality and different clinical factors derived from the development of atraumatic pneumothorax (PNX) and/or pneumomediastinum (PNMD) in critically ill patients as a consequence of COVID-19-associated lung weakness (CALW).

Design

Systematic review with meta-analysis.

Setting

Intensive care unit (ICU).

Participants

Original research evaluating patients, with or without the need for protective invasive mechanical ventilation (IMV), with a diagnosis of COVID-19 who had developed atraumatic PNX or PNMD on admission or during their hospital stay.

Interventions

Data of interest were obtained from each article and analysed and assessed by the Newcastle-Ottawa Scale. The risk of the variables of interest was assessed by data derived from studies including patients who developed atraumatic PNX or PNMD.

Main variables of interest

Mortality, mean ICU length of stay and mean PaO₂/FiO₂ at diagnosis.

Results

Data were collected from 12 longitudinal studies. Data from a total of 4,901 patients were included in the meta-analysis. A total of 1,629 patients had an episode of atraumatic PNX and 253 patients had an episode of atraumatic PNMD. Despite finding significantly strong associations, the high heterogeneity between studies means that interpretation of the results should be made with caution.

Conclusions

Mortality of COVID-19 patients was higher in those who developed atraumatic PNX and/or PNMD compared to those who did not. The mean PaO2/FiO2 index was lower in patients who developed atraumatic PNX and/or PNMD. We propose to group these cases under the term CAPD.

Risk factors of pneumothorax and pneumomediastinum in COVID-19: a matched case-control study

BACKGROUND

During the novel coronavirus disease-2019 pandemic, a considerable number of pneumothorax (PNX)/pneumomediastinum (PNM) associated with COVID-19 have been reported, and the incidence is higher in critically ill patients. Despite using a protective ventilation strategy, PNX/PNM still occurs in patients on invasive mechanical ventilation (IMV). This matched case-control study aims to identify the risk factors and clinical characteristics of PNX/PNM in COVID-19.

METHODS

This retrospective study enrolled adult patients with COVID-19, admitted to a critical care unit from March 1, 2020, to January 31, 2022. COVID-19 patients with PNX/PNM were compared, in a 1-2 ratio, to COVID-19 patients without PNX/PNM, matched for age, gender, and worst National Institute of Allergy and Infectious Diseases ordinal scale. Conditional logistic regression analysis was performed to assess the risk factors for PNX/PNM in COVID-19.

RESULTS

427 patients with COVID-19 were admitted during the period, and 24 patients were diagnosed with PNX/PNM. Body mass index (BMI) was significantly lower in the case group (22.8 kg/m² and 24.7 kg/m²; P = 0.048). BMI was statistically significant risk factor for PNX/PNM in univariate conditional logistic regression analysis [odds ratio (OR), 0.85; confidence interval (CI), 0.72-0.996; P = 0.044]. For patients on IMV support, univariate conditional logistic regression analysis showed the statistical significance of the duration from symptom onset to intubation (OR, 1.14; CI, 1.006-1.293; P = 0.041).

CONCLUSIONS

Higher BMI tended to show a protective effect against PNX/PNM due to COVID-19 and delayed application of IMV might be a contributive factor for this complication.

Pneumothorax in hospitalized COVID-19 patients with severe respiratory failure: Risk factors and outcome

PNX was described as an uncommon complication in COVID-19 patients but clinical risk predictors and the potential role in patient's outcome are still unclear. We assessed prevalence, risk predictors and mortality of PNX in hospitalized COVID- 19 with severe respiratory failure performing a retrospective observational analysis of 184 patients admitted to our COVID-19 Respiratory Unit in Vercelli from October 2020 to March 2021. We compared patients with and without PNX reporting prevalence, clinical and radiological features, comorbidities, and outcomes. Prevalence of PNX was 8.1% and mortality was >86% (13/15) significantly higher than in patients without PNX (56/169) (P < 0.001). PNX was more likely to occur in patients with a history of cognitive decline (HR: 31.18) who received non-invasive ventilation (NIV) (p < 0.0071) and with low P/F ratio (HR: 0.99, p = 0.004). Blood chemistry in the PNX subgroup compared to patients without PNX showed a significant increase in LDH (420 U/L vs 345 U/L, respectively p = 0.003), ferritin (1111 mg/dl vs 660 mg/dl, respectively p = 0.006) and decreased lymphocytes (HR: 4.440, p = 0.004). PNX may be associated with a worse prognosis in terms of mortality in COVID patients. Possible mechanisms may include the hyperinflammatory status associated with critical illness, the use of NIV, the severity of respiratory failure and cognitive impairment. We suggest, in selected patients showing low P/F ratio, cognitive impairment and metabolic cytokine storm, an early treatment of systemic inflammation in association with high-flow oxygen therapy as a safer alternative to NIV in order to avoid fatalities connected with PNX.

Pneumothorax in Critically Ill COVID-19 Patients in the Indian Subcontinent

Background and aims

To explore the incidence and risk factors, as well as mortality, in critically ill COVID-19 patients who developed pneumothorax (PTX) and/or pneumomediastinum (PNM).

Methods

A retrospective cohort study was undertaken to analyse data of all patients with moderate to severe COVID-19 disease who were either RTPCR positive or had a clinico-radiological diagnosis. The exposure group consisted of COVID-19 patients who presented with PTX/PNM, whereas the non-exposure group consisted of patients who did not develop PTX and/or PNM during the stay.

Results

Incidence of PTX/PNM was observed to be 1.9% among critically ill COVID-19 patients. 94.4% (17/18) of patients in the PTX group received positive pressure ventilation (PPV); the majority of these patients were on non-invasive ventilation when they developed PTX/PNM; only one patient was receiving conventional oxygen therapy. COVID-19 patients who developed PTX/PNM had 2.7 times higher mortality. A mortality rate of 72.2% was observed in COVID-19 patients who developed PTX/PNM.

Conclusion

Development of PTX/PNM in critically ill COVID-19 patients is associated with more severe disease involvement, and institution of PPV is an additional risk factor. Significantly high mortality was observed following PTX/PNM in critically ill COVID-19 patients and is an independent marker of poor prognosis in COVID-19 disease.

"Pneumomediastinum: A marker of severity in Covid-19 disease"

Objective

The goal of this study was to look at the incidence, risk factors, clinical characteristics, and radiological aspects of COVID-19 patients who developed pneumomediastinum and compare these features between those who died and those who survived.

Materials and methods

This retrospective observational study included COVID-19 patients having pneumomediastinum on CT from May 2020 to May 2021 in a COVID-19 care hospital. 1st wave patients were considered between the period of May 2020 to January 2021 and those in the second wave between February 2021 to May 2021. The clinical details were analyzed by a consultant intensivist and CT scans were read by a team of 6 resident radiologists and 5 experienced radiologists. Demographic data, co-morbidities, clinical parameters, hemodynamic markers, radiological involvement and associated complications were analyzed.

Results

During the study period, 10,605 COVID-19 patients were admitted to our hospital of which 5689 underwent CT scan. 66 patients were detected to have pneumomediastinum on CT; 26 of them in the first wave and 40 in the second wave. Out of 66, 28 patients were admitted to ICU, 9 during the first wave and 18 during the second wave. The overall incidence of developing pneumomediastinum was 1.16%. Incidence in the 1st wave was 1.0% and in the 2nd wave was 1.29%. The overall mortality rate in admitted COVID-19 patients was 12.83% while it was 43.9% in COVID-19 patients who developed pneumomediastinum. Incidence of pneumomediastinum and pneumothorax was high in patients with extensive parenchymal involvement. 59/66 (89%) cases of pneumomediastinum had severe CT score on imaging.

Conclusion

We conclude that pneumomediastinum is a marker of poor prognosis. Timely diagnosis of interstitial emphysema or pneumomediastinum will aid in planning early protective ventilation strategies and timely intervention of complications.

The use of lung ultrasound in COVID-19

This review article addresses the role of lung ultrasound in patients with coronavirus disease 2019 (COVID-19) for diagnosis and disease management. As a simple imaging procedure, lung ultrasound contributes to the early identification of patients with clinical conditions suggestive of COVID-19, supports decisions about hospital admission and informs therapeutic strategy. It can be performed in various clinical settings (primary care facilities, emergency departments, hospital wards, intensive care units), but also in outpatient settings using portable devices. The article describes typical lung ultrasound findings for COVID-19 pneumonia (interstitial pattern, pleural abnormalities and consolidations), as one component of COVID-19 diagnostic workup that otherwise includes clinical and laboratory evaluation. Advantages and limitations of lung ultrasound use in COVID-19 are described, along with equipment requirements and training needs. To infer on the use of lung ultrasound in different regions, a literature search was performed using key words "COVID-19", "lung ultrasound" and "imaging". Lung ultrasound is a noninvasive, rapid and reproducible procedure; can be performed at the point of care; requires simple sterilisation; and involves non-ionising radiation, allowing repeated exams on the same patient, with special benefit in children and pregnant women. However, physical proximity between the patient and the ultrasound operator is a limitation in the current pandemic context, emphasising the need to implement specific infection prevention and control measures. Availability of qualified staff adequately trained to perform lung ultrasound remains a major barrier to lung ultrasound utilisation. Training, advocacy and awareness rising can help build up capacities of local providers to facilitate lung ultrasound use for COVID-19 management, in particular in low- and middle-income countries.

Intrathoracic gas effusions in patients with COVID-19

Current evidence suggests that intrathoracic gas effusions (pneumomediastinum and pneumothorax) may be observed among COVID-19 patients even without mechanical ventilation. Here, we report 9 patients who developed spontaneous intrathoracic gas effusions in the absence of mechanical ventilation. The incidence of spontaneous intrathoracic gas effusions is low at 0.5% in hospitalized COVID-19 patients in the absence of respiratory support. Two patients (22.2%) had spontaneous pneumomediastinum, with or without subcutaneous emphysema. Three patients (33.3%) had pneumomediastinum associated with pneumothorax, with or without subcutaneous emphysema, and 4 patients (44.4%) had spontaneous pneumothorax. The Pneumothorax was unilateral in 66.6% of cases (6/9) but without location preference. Five of our patients were smokers, of whom 80% had isolated spontaneous pneumothorax. Other comorbidities included pulmonary tuberculosis in a single patient, diabetes in 2 patients and arterial hypertension in 1 patient. None of the patients had respiratory comorbidities. All of our patients were male. The average duration of hospital stay was 10 days (±6.63). All patients required oxygen therapy. Three patients (33.3%) with spontaneous pneumothorax required chest drainage. The evolution was favorable in 6 patients (66.7%) and worse in 3 cases (33.3%). The respiratory manifestations of COVID-19 have been stereotyped. Intrathoracic effusions may also be signs of COVID-19 with varying prognoses, or even the only presentation of the disease. This should be considered in clinical practice, and doctors are encouraged to request a SARS-CoV-2 test in this situation. Further investigations with a larger sample size are needed to identify the prognostic factors in COVID-19 patients with gas effusions.

Case of Spontaneous Pneumothorax After Recent COVID Pneumonia Hospitalization

An elderly man with COPD and heart failure was admitted to the Family Medicine Inpatient Service from the Emergency Department (ED) after experiencing acute onset of shortness of breath at home. He had recently been briefly hospitalized with COVID pneumonia. Upon arrival in the ED, he was requiring continuous positive airway pressure to maintain oxygen saturations. Overall, physical exam was notable for mild respiratory distress. Lab evaluation was unremarkable, but chest x-ray showed a right sided pneumothorax. Spontaneous pneumothoraces have been described in post-COVID cases, with COPD and mechanical ventilation thought to be risk factors. Treatment consists of supportive cares, needle decompression and thoracostomy if necessary. Providers should be aware of this rare albeit serious complication and monitor higher risk patients appropriately.

Retrospective analysis of COVID-19 patients developing otherwise rare complications

Background

Over the last 2 years, it has been felt that there was a disproportionate incidence of complications including pneumothorax, pneumomediastinum, and renal disease necessitating dialysis in patients with COVID-19 as compared to patients without COVID-19.

Methods

In a retrospective cohort, all patients were admitted to St. Joseph Mercy Oakland Hospital in Pontiac, Michigan, between March 2020 and November 2021. The data collected included age, sex, BMI, length of stay, COVID-19 PCR result, diagnosis of pneumothorax, diagnosis of pneumomediastinum, diagnosis of renal failure, orders for dialysis, and orders for mechanical ventilation.

Results

Nine thousand five hundred twenty-two patients are included in this study, with 35.6% (3,392 patients) COVID-19 suspected or confirmed positive and 64.4% (6130 patients) confirmed COVID-19 negative. There were 29 cases of pneumomediastinum and 24 cases of pneumothorax, none of which occurred in intubated patients. The incidence of pneumomediastinum (p = 0.001), CODE BLUE (p = 0.01), and mechanical ventilation (p = 0.001) was significantly higher in the COVID-19 positive/suspected group. There was no significant difference in incidence of pneumothorax (p = 0.294). The incidence of dialysis was significantly higher (p < 0.0001) in the COVID-19 negative group.

Conclusions

In review of prior literature and proposed mechanisms, we believe that it was possibly the damage that SARS-CoV-2 inflicts upon lung parenchyma that led to the increased incidence of pneumomediastinum. Given our mixed findings of incidences of pneumomediastinum, pneumothorax, and dialysis, our hope is to remain vigilant to uncover further disease associations and/or complications as more COVID-19 case data becomes available.

Outcomes of Percutaneous Tracheostomy for Patients With SARS-CoV-2 Respiratory Failure

BACKGROUND

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can cause severe respiratory failure leading to prolonged mechanical ventilation. Data are just emerging about the practice and outcomes of tracheostomy in these patients. We reviewed our experience with tracheostomies for SARS-CoV-2.

METHODS

We retrospectively reviewed the demographics, comorbidities, timing of mechanical ventilation, tracheostomy, and intensive care unit and hospital lengths of stay in SARS-CoV-2 patients who received tracheostomies performed by the interventional pulmonary team. A tertiary care, teaching hospital in Chicago, Illinois. From March 2020 to April 2021, our center had 473 patients intubated for SARS-CoV-2, and 72 (15%) had percutaneous bedside tracheostomy performed by the interventional pulmonary team.

RESULTS

Median time from intubation to tracheostomy was 20 (interquartile range: 16 to 25) days. Demographics and comorbidities were similar between early and late tracheostomy, but early tracheostomy was associated with shorter intensive care unit lengths of stay and a shorter total duration of ventilation. To date, 39 (54%) patients have been decannulated, 17 (24%) before hospital discharge; median time to decannulation was 22 (IQR: 18 to 36) days. Patients that were decannulated were younger (56 vs. 69 y). The rate of decannulation for survivors was 82%. No providers developed symptoms or tested positive for SARS-CoV-2.

CONCLUSION

Tracheostomy enhances care for patients with prolonged respiratory failure from SARS-CoV-2 since early tracheostomy is associated with shorter duration of critical care, and decannulation rates are high for survivors. It furthermore appears safe for both patients and operators.

THE EFFECT OF COVID-19 VACCINES ON PNEUMOTHORAX IN GERIATRIC PATIENTS HOSPİTALIZED IN INTENSIVE CARE UNIT DUE TO COVID-19

In our study, we examined the effect of COVID-19 vaccination on the incidence of pneumothorax in intensive care patients over age 65. COVID-19 intensive care patients that presented to our department between April 2020 and May 2021 during the COVID-19 pandemic were evaluated retrospectively. Patients were divided into two main groups, i.e., before and after the vaccination period. Patients were evaluated retrospectively for the following parameters: gender, age, side of pneumothorax, mortality, discharge, comorbidity, and additional pleural complications. The total number of patients was 87, i.e., 66 patients before vaccination and 21 patients after vaccination. When patients in the pre- and post-vaccination period were compared, there was a significant difference in the incidence of pneumothorax between the two groups (p<0.05). Pneumothorax was less common after vaccination. When patients with pneumothorax and tube thoracostomy were evaluated according to pre- and post-vaccination mortality, mortality was significantly higher (89%) in the pre-vaccination period (p<0.05). We consider that COVID-19 vaccines used in patients aged over 65 reduced the incidence of pleural complications, especially pneumothorax. We think that mortality due to pneumothorax in patients over 65 years of age was lower during the vaccination period. In addition, we think that bilateral pneumothorax was more common in the non-vaccinated period. As a result, we think that life-threatening pneumothorax and similar complications could be reduced by increasing the number of vaccines made in the COVID-19 pandemic and spreading it around the world.

Pneumothorax/pneumomediastinum and pre-existing lung pathology in ventilated COVID-19 patients: a cohort study

Background

There is an increasing number of reports on developing pneumothorax/pneumomediastinum among severe acute respiratory syndrome coronavirus disease 2019 (SARS-COVID-19) patients. The aim of our study was whether pre-existing diffuse lung pathology increases visceral pleural vulnerability resulting in pneumomediastinum and pneumothorax among mechanically ventilated COVID-19 patients?

Methods

A total of 138 consecutive COVID-19 patients admitted to the Intensive Care Unit of Petz Aladár University Teaching Hospital between 1st March 2020 and 1st February 2021 were included. Sixty/138 (43.48%) patients had one or more computer tomography scans of the chest. Analysis was focused on the image defined lung conditions during artificial ventilation.

Results

Thirteen out of 60 ventilated patients developed pneumothorax or pneumomediastinum proven by computer tomography (9.42%). Three/13 patients suffered from pre-existing lung parenchyma pathology, while 10/13 had only COVID-19 infection-related image abnormality. Forty-three/60 patient had healthy lung pre-COVID. Kruskal-Wallis test, Spearman correlation and Cox regression calculations did not reveal any statistically significant result proving increased vulnerability during pressure support therapy and visceral pleural breakdown in patients with pre-existing lung pathologies.

Conclusions

Pre-existing lung pathology does not increase the risk of onset of pneumothorax or pneumomediastinum in comparation with previously healthy lungs of ventilated COVID-19 patients.

Prognosis of Spontaneous Pneumothorax/Pneumomediastinum in Coronavirus Disease 2019: The CoBiF Score

Objectives: Pneumothorax and pneumomediastinum are associated with high mortality in invasively ventilated coronavirus disease 2019 (COVID-19) patients; however, the mortality rates among non-intubated patients remain unknown. We aimed to analyze the clinical features of COVID-19-associated pneumothorax/pneumomediastinum in non-intubated patients and identify risk factors for mortality. Methods: We searched PubMed Scopus and Embase from January 2020 to December 2021. We performed a pooled analysis of 151 patients with no invasive mechanical ventilation history from 17 case series and 87 case reports. Subsequently, we developed a novel scoring system to predict in-hospital mortality; the system was further validated in multinational cohorts from ten countries (n = 133). Results: Clinical scenarios included pneumothorax/pneumomediastinum at presentation (n = 68), pneumothorax/pneumomediastinum onset during hospitalization (n = 65), and pneumothorax/pneumomediastinum development after recent COVID-19 treatment (n = 18). Significant differences were not observed in clinical outcomes between patients with pneumomediastinum and pneumothorax (±pneumomediastinum). The overall mortality rate of pneumothorax/pneumomediastinum was 23.2%. Risk factor analysis revealed that comorbidities bilateral pneumothorax and fever at pneumothorax/pneumomediastinum presentation were predictors for mortality. In the new scoring system, i.e., the CoBiF system, the area under the curve which was used to assess the predictability of mortality was 0.887. External validation results were also promising (area under the curve: 0.709). Conclusions: The presence of comorbidity bilateral pneumothorax and fever on presentation are significantly associated with poor prognosis in COVID-19 patients with spontaneous pneumothorax/pneumomediastinum. The CoBiF score can predict mortality in clinical settings as well as simplify the identification and appropriate management of patients at high risk.

Pneumothorax in Critically Ill COVID-19 Patients: Prevalence, Analysis of Risk Factors and Clinical Outcomes

BACKGROUND

Previous studies have been conducted to assess pneumothorax. However, few studies were done to assess pneumothorax in COVID-19 patients in the intensive care unit (ICU).

OBJECTIVE

Our aim is to describe and analyze the prevalence, clinical characteristics, risk factors, and outcomes of COVID-19 pneumothorax patients in the intensive care unit.

METHODS

We performed a retrospective review of the medical records of 418 patients, who tested positive for COVID-19 by polymerase chain reaction test and required ICU admission in King Fahad Hospital of The University from 02/01/2020 to 01/09/2021. A total number of 36 pneumothorax patients were included in the study.

RESULTS

Of 418 patients who were followed up in the intensive care unit as COVID-19 cases, 36 patients developed a pneumothorax (8.61%). The mean age of the patients was 55.6 ± 15.06 years, 23 patients were male, and 13 were female. Seventeen patients were obese, and only one patient was an active smoker. Twenty-four patients had at least one comorbidity; hypertension was the most common. Thirty-two patients were intubated, and the duration of intubation was 23.23 ±15.9 days. The time from intubation to pneumothorax development was 8.8 ± 9.3 days. Six patients were on bilevel positive airway pressure ventilation (BIPAP), 2 patients on continuous positive airway pressure ventilation (CPAP), 3 patients on High-Flow Nasal Cannula ventilation (HFNC), 9 patients on pressure-control ventilation (PC), and 16 patients on pressure regulated volume control ventilation (PRVC). Of 36 patients, 26 died, and the mortality rate was 72.2%.

CONCLUSION

Our study showed that risk factors of pneumothorax occurrence in COVID-19 critically ill patients include male patients, hypertension, diabetes mellitus, endotracheal intubation and mechanical ventilation. More efforts should be made to determine the risk factors and assess the outcomes of those patients to develop preventive measures and management guidelines.

Evaluation of the Prevalence of Barotrauma and Affecting Factors in Patients with COVID-19 during Follow-Up in the Intermediate Care Unit

It is known that pneumothorax (PX) and pneumomediastinum (PM) develop due to COVID-19 disease. The objective of our study was to determine the prevalence of PX/PM due to COVID-19 in the intermediate intensive care unit (IMCU) and to evaluate the factors causing barotrauma and also the clinical outcomes of these patients. A total of 283 non-intubated patients with COVID-19 pneumonia followed up in the IMCU in a 1-year period were included in the study. The patients were classified as group 1 (having barotrauma) and group 2 (without barotrauma). The rate of barotrauma was 8.1% (n = 23, group 1). PX developed on the right hemithorax in 12 (70.6%) patients. Group 1 had statistically significantly higher 28-day mortality rates compared with group 2 (p = 0.014). The eosinophil and d-dimer levels of the patients in group 1 were higher, while C-reactive protein (CRP), fibrinogen, and albumin levels were lower than Group 2 (p < 0.001, p = 0.017, p = 0.001, p < 0.001), and p < 0.001, respectively). The similar rates of NIMV administration in our study groups support that barotrauma is not the only mechanism in the development of PX/PM. The findings of high blood eosinophil count and low blood levels of CRP, albumin, and fibrinogen in the barotrauma group of our study might be a pathfinder for future studies.

Air leaks in COVID-19

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

Clinical and Gene Features of SARS-CoV-2-Positive Recurrence in Patients Recovered From COVID-19

There are still frequent reports that a number of recovered coronavirus disease 2019 (COVID-19) patients following discharge have re-detectable positive (RP) results by RT-PCR. Understanding the clinical and molecular characteristics of RP patients may have implications for curbing the COVID-19 pandemic. In this study, 318 COVID-19 convalescent patients, including 59 RP patients and 259 non-RP (NRP) patients, were enrolled. Among RP patients, women accounted for a significantly high proportion (67.8%), and the titers of IgG and IgM antibodies in this group were also significantly high. Differentially expressed genes (DEGs), including 692 upregulated and 383 downregulated genes, overlapped in two public GEO datasets containing RP and NRP blood cell samples. Enrichment analysis indicated that these DEGs were related to several key signaling pathways, such as viral infection, immune activation, and inflammatory responses. Importantly, 59 indicator genes constituting the core network exhibited high diagnostic values and were correlated with markers of different immune cells. Among these, 12 drug-related genes were associated with the RP results. Our work suggests that, in addition to clinically available features, blood cell transcriptome sequencing can be performed to obtain gene signatures for diagnosis of RP patients.

Management of spontaneous pneumothorax in patients with COVID-19

OBJECTIVES

The coronavirus disease 2019 (COVID-19) pneumonia may cause cystic features of lung parenchyma which can resolve or progress to larger blebs. Pneumothorax was more likely in patients with neutrophilia, severe lung injury and a prolonged clinical course. The timely diagnosis and management will reduce COVID-19-associated morbidity and mortality.

METHODS

We present 11 cases of spontaneous pneumothorax managed with chest tube thoracostomy or high-dose oxygen therapy. Isolated spontaneous pneumothorax was detected in all cases.

RESULTS

Eight cases were male and 3 cases were female. There were bilateral ground-glass opacities or pulmonary infiltrates in the parenchyma of the 10 cases. We detected neutrophilia, lymphopaenia and increased C-reactive protein, Ferritin, lactate dehydrogenase, D-Dimer, interleukin-6 levels in almost all cases. Chest tube thoracostomy was sufficient to treat pneumothorax in our 9 of case. In 2 cases, pneumothorax healed with high-dose oxygen therapy. Favipiravir and antibiotic treatment were given to different 10 patients. In our institution, all patients with COVID-19 infection were placed on prophylactic or therapeutic anticoagulation, unless contraindicated. The treatments of patients diagnosed with secondary spontaneous pneumothorax during the pandemic period and those diagnosed with secondary spontaneous pneumothorax in the previous 3 years were compared with the durations of tube thoracostomy performed in both groups.

CONCLUSIONS

The increased number of cases of pneumothorax suggests that pneumothorax may be a complication of COVID-19 infection. During medical treatment of COVID-19, pneumothorax may be the only reason for hospitalization. Although tube thoracostomy is a sufficient treatment option in most cases, clinicians should be aware of the difficulties that may arise in diagnosis and treatment.

Macklin effect on baseline chest CT scan accurately predicts barotrauma in COVID-19 patients

Purpose

To validate the role of Macklin effect on chest CT imaging in predicting subsequent occurrence of pneumomediastinum/pneumothorax (PMD/PNX) in COVID-19 patients.

Materials and methods

This is an observational, case-control study. Consecutive COVID-19 patients who underwent chest CT scan at hospital admission during the study time period (October 1st, 2020–April 31st, 2021) were identified. Macklin effect accuracy for prediction of spontaneous barotrauma was measured in terms of sensitivity, specificity, positive (PPV) and negative predictive values (NPV).

Results

Overall, 981 COVID-19 patients underwent chest CT scan at hospital arrival during the study time period; 698 patients had radiological signs of interstitial pneumonia and were considered for further evaluation. Among these, Macklin effect was found in 33 (4.7%), including all 32 patients who suffered from barotrauma lately during hospital stay (true positive rate: 96.9%); only 1/33 with Macklin effect did not develop barotrauma (false positive rate: 3.1%). No barotrauma event was recorded in patients without Macklin effect on baseline chest CT scan. Macklin effect yielded a sensitivity of 100% (95% CI: 89.1–100), a specificity of 99.85% (95% CI: 99.2–100), a PPV of 96.7% (95% CI: 80.8–99.5), a NPV of 100% and an accuracy of 99.8% (95% CI: 99.2–100) in predicting PMD/PNX, with a mean advance of 3.2 ± 2.5 days. Moreover, all Macklin-positive patients developed ARDS requiring ICU admission and, in 90.1% of cases, invasive mechanical ventilation.

Conclusions

Macklin effect has high accuracy in predicting PMD/PNX in COVID-19 patients; it is also an excellent predictor of disease severity.

Incidence and Clinical Features of Pneumomediastinum and Pneumothorax in COVID-19 Pneumonia

Background

Pneumothorax (PTX) and pneumomediastinum (PM), collectively termed here “air leak”, are now well described complications of severe COVID-19 pneumonia across several case series. The incidence is thought to be approximately 1% but is not definitively known.

Objectives

To report the incidence and describe the demographic features, risk factors and outcomes of patients with air leak as a complication of COVID-19.

Methods

A retrospective observational study on all adult patients with COVID-19 admitted to Watford General Hospital, West Hertfordshire NHS Trust between March 1st 2020 and Feb 28^th 2021. Patients with air leak were identified after reviewing both chest radiographs (CXRs) and axial imaging (CT Thorax) with confirmatory radiology reports inclusive of the terms PTX and/or PM.

Results

Air leak occurred with an incidence of 0.56%. Patients with air leak were younger and had evidence of more severe disease at presentation, including a higher median CRP and number of abnormal zones affected on chest radiograph. Asthma was a significant risk factor in the development of air leak (OR 13.4 [4.7-36.4]), both spontaneously and following positive pressure ventilation. CPAP and IMV were also associated with a greater than six fold increase in the risk of air leak (OR 6.4 [2.5-16.6] and 9.8 [3.7-27.8] respectively). PTX, with or without PM, in the context of COVID-19 pneumonia was almost universally fatal whereas those with alone PM had a lower risk of death.

Conclusion

Despite the global vaccination programme, patients continue to develop severe COVID-19 disease and may require respiratory support. This study demonstrates the importance of identifying that deterioration in such patients may be resultant from PTX or PM, particularly in asthmatics and those managed with positive pressure ventilation.

A holistic investigation of the global outcomes of spontaneous pneumothorax during 1980-2021, including the COVID-19 pandemic A bibliometric approach

BACKGROUND

During coronavirus pandemic, despite the increase in the number of studies on spontaneous pneumothorax (SP), there is not enough bibliometric study in the literature. In this study, it was aimed to analyze scientific articles published on SP.

METHODS

Studies published on SP between 1980 and 2021 were obtained from the Web of Science database and analyzed using statistical and bibliometric methods. Spearman correlation coefficient was used for correlation studies. The exponential smoothing estimator was used to forecast publication trend for coming years. Network visualization maps were used to analyze citations and identify trending topics.

RESULTS

A total of 2422 publications were found. 1403 (57.9%) of these publications were articles. The articles on SP have increased with a non-linear trend in recent years. The top 5 contributors to the literature were USA (231, 16.4%), Japan (161, 11.4%), United Kingdom (98, 6.9%), France (81, 5.7%), and Taiwan (78, 5.5%). The top 3 most active institutions were National Taiwan University Hospital (22, 1.5%), Catholic University Korea (19, 1.3%), and National Taiwan University (19, 1.3%). The top 3 journals that published the most articles were Chest (51), Annals of Thoracic Surgery (46), and Journal of Thoracic Disease (45). The most studied subjects were primary SP, recurrence, thoracoscopy, pleurodesis, video-assisted thoracoscopic surgery, COVID-19, video-assisted thoracic surgery, chest tube(s), and secondary spontaneous pneumothorax. According to trend topics analysis, the keywords studied in recent years are COVID-19, chest tubes, pneumonia, subcutaneous emphysema, risk factors, dyspnea, primary SP, FLCN gene, tension pneumothorax, uniportal, postoperative recurrence, secondary spontaneous pneumothorax, chronic obstructive pulmonary disease, and uniportal.

CONCLUSION

In this comprehensive bibliometric study, we summarized 1403 articles about SP, which has an increasing trend in the number of articles during the COVID-19 pandemic process. This article can be a useful resource for clinicians and scientists through presenting a summary of worldwide studies related to SP, including the ones during COVID-19 pandemic.

Spontaneous pneumothorax, pneumomediastinum and subcutaneous emphysema in non-ventilated COVID-19 patients

Aim:

Pneumothorax (PNX), pneumomediastinum (PMD) and subcutaneous emphysema (SCE) are COVID-19 complications related to positive-pressure ventilation. We analyzed the pathophysiology of these complications without ventilation.

Patients & methods:

Out of 1845 admitted COVID-19 patients, we retrospectively collected data for 15 patients, from a tertiary medical center, from 1 October 2020 to 31 March 2021.

Results:

Five patients suffered from spontaneous PNX, 8/15 developed PMD and 8/15 developed SCE. The mean BMI was 29.7, as most patients were obese or overweight. Most patients had lymphocytopenia and increased C-reactive protein, ferritin and lactate dehydrogenase levels. Eleven patients succumbed to the disease.

Conclusion:

Risk factors of spontaneous PNX, PMD and SCE in COVID-19 patients need further investigations by conducting more comprehensive case–control studies.

We have investigated spontaneous alveolar rupture as a complication in 15 COVID-19 patients. Manifested as pneumothorax, pneumomediastinum and subcutaneous emphysema, these complications are less common in patients without mechanical ventilation. Management of these patients was either conservative or by insertion of a chest tube. Eventually, 11 out of 15 patients have passed away due to respiratory failure.

Pneumothorax and pneumomediastinum in patients with COVID-19: A retrospective study from tertiary care institute in India

COVID-19 is associated with rarer extra-parenchymal manifestations, namely pneumothorax (PTX) and pneumomediastinum (PM) leading to complications and increased mortality. The study aims to describe the prevalence, risk factors for mortality, radiological characteristics and outcome of PTX/PM in patients admitted with COVID-19. This was a retrospective, single-centre, observational study in patients with confirmed COVID-19 presenting with non-iatrogenic PTX/PM from April 2020 to May 2021. Details pertaining to demographics, presentation, radiological characteristics, management and outcome were collected. Cases were classified into spontaneous and barotraumatic PTX/PM and a between-group comparison was performed using Chi-square and t-test. A total of 45 cases (mean age: 53.2 years, 82% males) out of 8,294 confirmed COVID-19 patients developed PTX/PM, the calculated incidence being 0.54%. 29 cases had spontaneous PTX/PM and the remaining 17 cases were attributed to barotrauma. The most common comorbidities were diabetes-mellitus (65.3%) and hypertension (42.3%). The majority of the cases had large PTX (62.1%) with tension in 8 cases (27.5%). There were predominant right-sided pneumothoraces and five were diagnosed with bronchopleural fistula. 37.7% of cases had associated subcutaneous emphysema. The median duration of PTX/PM from symptom onset was delayed at 22.5 and 17.6 days respectively. The mean CT severity score (CTSS) was 20.5 (± 4.9) with fibrosis (53.8%), bronchiectatic changes (50%) and cystic-cavitary changes (23%). There was no statistically significant difference between the spontaneous and barotrauma cohort. 71% of cases died and the majority belonged to the barotrauma cohort. It is imperative to consider the possibility of PTX/PM in patients having COVID-19, especially in those with deterioration in the disease course, both in spontaneously breathing and mechanically ventilated patients. These patients may also have a high incidence of death, reflecting the gravity of COVID-19.

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

Introduction

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

Method

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

Results

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

Conclusion

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

How to cite this article

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

Risk Factors, Characteristics, and Outcome in Non-Ventilated Patients with Spontaneous Pneumothorax or Pneumomediastinum Associated with SARS-CoV-2 Infection

Background and Objectives

Spontaneous pneumothorax (SP) and spontaneous pneumomediastinum (SPM) have frequently been cited as complications associated with coronavirus disease 2019 (COVID-19) pneumonia, with especially poor prognosis in mechanically ventilated patients. The current literature is controversial regarding the potential risk factors for developing SP or SPM (SP-SPM) in non-ventilated COVID-19 patients. Our research addressed a twofold objective: (a) to investigate the characteristics of patients with SP-SPM (both with and without COVID-19) and compare them to patients with sole COVID-19; (b) to quantify the risk of in-hospital mortality associated with SP-SPM and COVID-19.

Patients and Methods

A retrospective case–control study was conducted in the emergency departments (ED) of two tertiary hospitals in Timisoara, Romania, over one year (1st April 2020‒31st March 2021; 64,845 records in total) and 70 cases of SP-SPM were identified (both SARS-CoV-2 positives and negatives). The control group comprised COVID-19 patients with no SP-SPM, included at a 2:1 ratio. Logistic regression was employed to quantify the in-hospital mortality risk associated with age, SP-SPM, and COVID-19.

Results

SP-SPM and COVID-19 were connected with prolonged hospitalization, a higher percentage of intensive care admission, and a higher mortality. SP-SPM increased the odds of death by almost four times in patients of the same age, gender, smoking status, and SARS-CoV-2 infection: OR = 3.758, 95% CI (1.443–9.792). Each additional year of age added 9.4% to the mortality risk: OR = 1.094, 95% CI (1.054–1.135).

Conclusion

ED physicians should acknowledge these potential risks when attending COVID-19 patients with SP-SPM.

Pulmonary barotrauma in COVID-19: A systematic review and meta-analysis

BACKGROUND

An ever-increasing number of studies have reported an increased incidence of spontaneous pulmonary barotrauma such as pneumothorax, pneumomediastinum, and subcutaneous emphysema in patients with COVID-19. We conducted this systematic review and meta-analysis to assess the value and significance of the available data.

METHODS

A thorough systematic search was conducted to identify studies of barotrauma in hospitalized patients with COVID-19. Data analysis of case reports was done using a statistical package for the social sciences (SPSS) version 22, and meta-analysis was performed using CMA-3.

RESULTS

We identified a total of 4488 studies after thorough database searching.118 case reports and series, and 15 observational studies were included in the qualitative analysis. Fifteen studies were included in the quantitative analysis. The observational studies reported barotrauma in 4.2% (2.4-7.3%) among hospitalized patients; 15.6% (11-21.8%) among critically ill patients; and 18.4% (13-25.3%) in patients receiving invasive mechanical ventilation, showing a linear relationship of barotrauma with the severity of the disease. In addition, barotrauma was associated with a longer length of hospital stay, more extended ICU stay, and higher in-hospital mortality. Also, a slightly higher odds of barotrauma was seen in COVID-19 ARDS compared with non-COVID-19 ARDS.

CONCLUSION

COVID-19 pneumonia is associated with a higher incidence of barotrauma. It presents unique challenges for invasive and non-invasive ventilation management. Further studies are required to unravel the underlying pathophysiology and develop safer management strategies.

Prognostic factors and their effects on mortality in patients with COVID-19 with pneumothorax

Background

The aim of this study was to investigate the factors affecting pneumothorax development, lung expansion difficulty, and the impact on mortality in novel coronavirus 2019 (COVID-19) patients.

Methods

Between March 2020 and January 2021, a total of 6,108 COVID-19 patients (3,050 males, 3,058 females; mean age: 49±17.6 years, range, 12 to 89 years) who presented to our hospital were retrospectively analyzed. The patients were divided into two groups. Group 1 (the COVID-19-pneumothorax group) consisted of patients developing pneumothorax while under treatment for COVID-19. Group 2 (COVID-19-without pneumothorax group) consisted of consecutive patients with pulmonary involvement during the same period, requiring intensive care, but not developing pneumothorax. Biochemical test results were examined for the day of hospitalization, day of transfer to intensive care unit, and Day 5 of intensive care unit stay. Lung parenchyma involvement rates on thoracic computed tomography, duration of drainage, duration of intensive care unit stay, and morbidity/mortality data were investigated.

Results

Of all patients with COVID-19, 2,342 were admitted to our clinic and 460 needed intensive care. Pneumothorax developed in 21 patients (0.34% of all patients and 0.9% of hospitalized patients). Significant involvement diffusion on computed tomography, ferritin and D-dimer elevation, and low lymphocyte (%) values were observed in the COVID-19 patients with pneumothorax. Pneumothorax development, and ferritin and D-dimer elevation were most correlated with mortality at regression analysis. There was a significant difference in difficulty in lung expansion between COVID-19 patients who developed pneumothorax and who did not.

Conclusion

Pneumothorax may develop in COVID-19 patients whose biochemical parameters worsen, and expansion difficulty may be experienced, which is likely to be associated with mortality.

Bilateral Spontaneous Pneumothorax in a COVID-19 and HIV-Positive Patient: A Case Report

This case report describes a 60 year-old Black-American male with a past medical history of human immunodeficiency virus (HIV) infection and hyperthyroidism, who suffered a bilateral spontaneous pneumothorax (SP) in the setting of coronavirus disease 2019 (COVID-19) pneumonia. SP is a well-established complication in HIV-positive patients and only recently has been associated with severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection. While HIV and COVID-19 infections have been independently linked with increased risk of SP development, it is unknown if both infections interact in a synergistic fashion to exacerbate SP risk. According to the Centers for Disease Control and Prevention (CDC), patients living with HIV have a higher risk of developing severe COVID-19 infection and the mechanism remains to be elucidated. To the best of our knowledge, this is the first report of a HIV-positive patient, who in the setting of SARS-CoV-2 infection, developed bilateral apical spontaneous pneumothorax and was later found to have a left lower lobe tension pneumothorax. This case highlights the importance of considering SP on the differential diagnosis when HIV-positive patients suddenly develop respiratory distress in the setting of SARS-CoV-2 infection.

Increased frequency of pneumothorax and pneumomediastinum in COVID-19 patients admitted in the ICU: A multicentre study from Mumbai, India

BACKGROUND

There are limited data regarding the incidence of pneumothorax in COVID-19 patients as well as the impact of the same on patient outcomes.

METHODS

A retrospective review of the medical records at three large tertiary care hospitals in Mumbai was performed to identify patients hospitalised with COVID-19 from March 2020 to October 2020. The presence of pneumothorax and/or pneumomediastinum was noted when chest radiographs or CT scans were performed. Demographic and clinical characteristics of patients who developed air leak were recorded.

RESULTS

4,906 patients with COVID-19 were admitted, with 1,324 (27%) having severe COVID-19 disease. The overall incidence of pneumothorax and/or pneumomediastinum in patients with severe disease was 3.2% (42/1,324). Eighteen patients had pneumothorax, 16 had pneumomediastinum and 8 patients had both. Fourteen patients (33.3%) developed this complication breathing spontaneously, 28 patients (66.6%) developed it during mechanical ventilation. Overall mortality in this cohort was 74%, compared with 17% in the COVID-19 patients without pneumothorax (p<0.001).

CONCLUSIONS

Our study demonstrates that air leaks occur with a higher frequency in patients with COVID-19 than in other ICU patients. When present, such air leaks contributed to poor outcomes with almost 74% mortality rates in these patients.

Incidence of Pneumothorax and Pneumomediastinum in 497 COVID-19 Patients with Moderate-Severe ARDS over a Year of the Pandemic: An Observational Study in an Italian Third Level COVID-19 Hospital

(1) Background: COVID-19 is a novel cause of acute respiratory distress syndrome (ARDS). Indeed, with the increase of ARDS cases due to the COVID-19 pandemic, there has also been an increase in the incidence of cases with pneumothorax (PNX) and pneumomediastinum (PNM). However, the incidence and the predictors of PNX/PMN in these patients are currently unclear and even conflicting. (2) Methods: The present observational study analyzed the incidence of barotrauma (PNX/PNM) in COVID-19 patients with moderate-severe ARDS hospitalized in a year of the pandemic, also focusing on the three waves occurring during the year, and treated with positive-pressure ventilation (PPV). We collected demographic and clinical data. (3) Results: During this period, 40 patients developed PNX/PNM. The overall incidence of barotrauma in all COVID-19 patients hospitalized in a year was 1.6%, and in those with moderate-severe ARDS in PPV was 7.2% and 3.8 events per 1000 positive-pressure ventilator days. The incidence of barotrauma in moderate-severe ARDS COVID-19 patients during the three waves was 7.8%, 7.4%, and 8.7%, respectively. Treatment with noninvasive respiratory support alone was associated with an incidence of barotrauma of 9.1% and 2.6 events per 1000 noninvasive ventilator days, of which 95% were admitted to the ICU after the event, due to a worsening of respiratory parameters. The incidence of barotrauma of ICU COVID-19 patients in invasive ventilation over a year was 5.8% and 2.7 events per 1000 invasive ventilator days. There was no significant difference in demographics and clinical features between the barotrauma and non-barotrauma group. The mortality was higher in the barotrauma group (17 patients died, 47.2%) than in the non-barotrauma group (170 patients died, 37%), although this difference was not statistically significant (p = 0.429). (4) Conclusions: The incidence of PNX/PNM in moderate-severe ARDS COVID-19 patients did not differ significantly between the three waves over a year, and does not appear to be very different from that in ARDS patients in the pre-COVID era. The barotrauma does not appear to significantly increase mortality in COVID-19 patients with moderate-severe ARDS if protective ventilation strategies are applied. Attention should be paid to the risk of barotrauma in COVID-19 patients in noninvasive ventilation because the event increases the probability of admission to the intensive care unit (ICU) and intubation.

Successful use of endobronchial valve for persistent air leak in a patient with COVID-19 and bullous emphysema

Patients with SARS-CoV-2 pneumonia can suffer from pneumothorax and persistent air leak (PAL). The pneumothorax occurs with or without pre-existing lung disease. PAL refers to air leak lasting more than 5-7 days and arises due to bronchopleural or alveolopleural fistula. The management of PAL can be challenging as a standard management guideline is lacking. Here we present the case of a 42-year-old smoker with COVID-19 who presented to the hospital with fever, cough, acute left-sided chest pain and shortness of breath. He suffered from a large left-sided pneumothorax requiring immediate chest tube drainage. Unfortunately, the air leak persisted for 13 days before one-way endobronchial valve (EBV) was used with complete resolution of the air leak. We also review the literature regarding other cases of EBV utilisation for PAL in patients with COVID-19.

A case-control analysis of stroke in COVID-19 patients: Results of unusual manifestations of COVID-19-study 11

OBJECTIVE

We investigated the incidence, predictor variables, clinical characteristics, and stroke outcomes in patients with COVID-19 seen in emergency departments (EDs) before hospitalization.

METHODS

We retrospectively reviewed all COVID-19 patients diagnosed with stroke during the COVID-19 outbreak in 62 Spanish EDs. We formed two control groups: COVID-19 patients without stroke (control A) and non-COVID-19 patients with stroke (control B). We compared disease characteristics and four outcomes between cases and controls.

RESULTS

We identified 147 strokes in 74,814 patients with COVID-19 seen in EDs (1.96‰, 95% confidence interval [CI] = 1.66‰ to 2.31‰), being lower than in non-COVID-19 patients (6,541/1,388,879, 4.71‰, 95% CI = 4.60‰ to 4.83‰; odds ratio [OR] = 0.42, 95% CI = 0.35 to 0.49). The estimated that standardized incidences of stroke per 100,000 individuals per year were 124 and 133 for COVID-19 and non-COVID-19 individuals, respectively (OR = 0.93 for COVID patients, 95% CI = 0.87 to 0.99). Baseline characteristics associated with a higher risk of stroke in COVID-19 patients were hypertension, diabetes mellitus, and previous cerebrovascular and coronary diseases. Clinically, these patients more frequently presented with confusion, decreased consciousness, and syncope and higher D-dimer concentrations and leukocyte count at ED arrival. After adjustment for age and sex, the case group had higher hospitalization and intensive care unit (ICU) admission rates (but not mortality) than COVID-19 controls without stroke (OR = 3.41, 95% CI = 1.27 to 9.16; and OR = 3.79, 95% CI = 1.69 to 8.50, respectively) and longer hospitalization and greater in-hospital mortality than stroke controls without COVID-19 (OR = 1.55, 95% CI = 1.24 to 1.94; and OR = 1.77, 95% CI = 1.37 to 2.30, respectively).

CONCLUSIONS

The incidence of stroke in COVID-19 patients presenting to EDs was lower than that in the non-COVID-19 reference sample. COVID-19 patients with stroke had greater need for hospitalization and ICU admission than those without stroke and longer hospitalization and greater in-hospital mortality than non-COVID-19 patients with stroke.

Pneumothorax and/or Pneumomediastinum Worsens the Prognosis of COVID-19 Patients with Severe Acute Respiratory Failure: A Multicenter Retrospective Case-Control Study in the North-East of Italy

Pneumothorax (PNX) and pneumomediastinum (PNM) are potential complications of COVID-19, but their influence on patients’ outcomes remains unclear. The aim of the study was to assess incidence, risk factors, and outcomes of severe COVID-19 complicated with PNX/PNM. Methods: A retrospective multicenter case-control analysis was conducted in COVID-19 patients admitted for respiratory failure in intermediate care units of the Treviso area, Italy, from March 2020 to April 2021. Clinical characteristics and outcomes of patients with and without PNX/PNM were compared. Results: Among 1213 patients, PNX and/or PNM incidence was 4.5%. Among these, 42% had PNX and PNM, 33.5% only PNX, and 24.5% only PNM. COVID-19 patients with PNX/PNM showed higher in-hospital (p = 0.02) and 90-days mortality (p = 0.048), and longer hospitalization length (p = 0.002) than COVID-19 patients without PNX/PNM. At PNX/PNM occurrence, one-third of subjects was not mechanically ventilated, and the respiratory support was similar to the control group. PNX/PNM occurrence was associated with longer symptom length before hospital admission (p = 0.005) and lower levels of blood lymphocytes (p = 0.017). Conclusion: PNX/PNM are complications of COVID-19 associated with a worse prognosis in terms of mortality and length of hospitalization. Although they are more frequent in ventilated patients, they can occur in non-ventilated, suggesting that mechanisms other than barotrauma might contribute to their presentation.