COVID-19 pneumonia - increased incidence of pneumothorax/mediastinal emphysema after invasive mechanical and non-invasive ventilation.

Introduction: COVID pneumonia can lead to pneumomediastinum or pneumothorax during non-invasive or invasive mechanical ventilation. This affects the prognosis. Methodology: During the study period, 121 patients with SARS-CoV-2 infections and invasive or non-invasive ventilation therapy were recorded in our hospital. All patients with a pneumothorax or pneumomediastinum were analyzed in more detail. Result(s): Pneumothorax and pneumomediastinum occurred in 12 patients and resulted in 7 deaths. Discussion(s): The incidence of pneumothorax with COVID infection ranges from 0.56 to 1%, reaching 3.5% in our own studies and 4.2% under invasive mechanical ventilation. The incidence of pneumomediastinum was 10% and 9.2% in our own patients. Overall mortality was 58.3% and similar to that reported in the literature, up to 60%.Copyright © 2023 Dustri-Verlag Dr. K. Feistle.

"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 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.

Clinical use of Macklin-like radiological sign (Macklin effect): A systematic review.

INTRODUCTION: Recent studies suggested that Macklin sign is a predictor of barotrauma in patients with acute respiratory distress syndrome (ARDS). We performed a systematic review to further characterize the clinical role of Macklin. METHODS: PubMed, Scopus, Cochrane Central Register and Embase were searched for studies reporting data on Macklin. Studies without data on chest CT, pediatric studies, non-human and cadaver studies, case reports and series including <5 patients were excluded. The primary objective was to assess the number of patients with Macklin sign and barotrauma. Secondary objectives were: occurrence of Macklin in different populations, clinical use of Macklin, prognostic impact of Macklin. RESULTS: Seven studies enrolling 979 patients were included. Macklin was present in 4-22% of COVID-19 patients. It was associated with barotrauma in 124/138 (89.8%) of cases. Macklin sign preceded barotrauma in 65/69 cases (94.2%) 3-8 days in advance. Four studies used Macklin as pathophysiological explanation for barotrauma, two studies as a predictor of barotrauma and one as a decision-making tool. Two studies suggested that Macklin is a strong predictor of barotrauma in ARDS patients and one study used Macklin sign to candidate high-risk ARDS patients to awake extracorporeal membrane oxygenation (ECMO). A possible correlation between Macklin and worse prognosis was suggested in two studies on COVID-19 and blunt chest trauma. CONCLUSIONS: Increasing evidence suggests that Macklin sign anticipate barotrauma in patients with ARDS and there are initial reports on use of Macklin as a decision-making tool. Further studies investigating the role of Macklin sign in ARDS are justified.

Venovenous Extracorporeal Membrane Oxygenation in Awake Non-Intubated Patients With COVID-19 ARDS at High Risk for Barotrauma.

OBJECTIVES: To assess the efficacy of an awake venovenous extracorporeal membrane oxygenation (VV-ECMO) management strategy in preventing clinically relevant barotrauma in patients with coronavirus disease 2019 (COVID-19) with severe acute respiratory distress syndrome (ARDS) at high risk for pneumothorax (PNX)/pneumomediastinum (PMD), defined as the detection of the Macklin-like effect on chest computed tomography (CT) scan. DESIGN: A case series. SETTING: At the intensive care unit of a tertiary-care institution. PARTICIPANTS: Seven patients with COVID-19-associated severe ARDS and Macklin-like radiologic sign on baseline chest CT. INTERVENTIONS: Primary VV-ECMO under spontaneous breathing instead of invasive mechanical ventilation (IMV). All patients received noninvasive ventilation or oxygen through a high-flow nasal cannula before and during ECMO support. The study authors collected data on cannulation strategy, clinical management, and outcome. Failure of awake VV-ECMO strategy was defined as the need for IMV due to worsening respiratory failure or delirium/agitation. The primary outcome was the development of PNX/PMD. MEASUREMENTS AND MAIN RESULTS: No patient developed PNX/PMD. The awake VV-ECMO strategy failed in 1 patient (14.3%). Severe complications were observed in 4 (57.1%) patients and were noted as the following: intracranial bleeding in 1 patient (14.3%), septic shock in 2 patients (28.6%), and secondary pulmonary infections in 3 patients (42.8%). Two patients died (28.6%), whereas 5 were successfully weaned off VV-ECMO and were discharged home. CONCLUSIONS: VV-ECMO in awake and spontaneously breathing patients with severe COVID-19 ARDS may be a feasible and safe strategy to prevent the development of PNX/PMD in patients at high risk for this complication.

Pneumomediastinum Associated with COVID-19: A Case Series

Coronavirus disease 2019 (COVID-19), caused by the new coronavirus SARS-CoV-2, is an infectious disease that has caused an increase in hospitalizations for pneumonia;the spectrum of clinical presentation is variable. One such presentation, pneumomediastinum (PM), is defined as the presence of air or some other gas in the mediastinum. It is a rare condition, usually benign and self-limited;it has been seen in patients with COVID-19. Although most cases are, as explained above, self-limited and in addition, can be managed conservatively, close monitoring is recommended, as PM can cause life-threatening hemodynamic and respiratory disturbances. We present a case series of 4 patients with SARS-CoV-2 infection, in whom PM was found, and who were admitted to the Regional Hospital of High Specialty of the Yucatan Peninsula during the period of May 2020 through August 2020.

Pneumomediastinum in COVID-19 Patients with Acute Respiratory Distress Syndrome.

BACKGROUND: Pneumomediastinum, an uncommon entity, has been on the rise with increasing cases of COVID-Acute respiratory distress syndrome. It has been unclear whether this entity represents an indicator of poor clinical outcome or not. The aims of this study were to find out the incidence of pneumomediastinum in COVID-Acute respiratory distress syndrome patients, describe their clinical characteristics and try to explain its plausible mechanisms.. METHODS: A descriptive, cross-sectional study was carried out in the ICU of our hospital among 280 patients admitted with COVID-Acute respiratory distress syndrome over a period of 6 months. Demographics along with various clinical, laboratory, and radiological parameters were analyzed. Relevant statistical analyses were done to summarize our findings. RESULTS: The incidence of pneumomediastinum in COVID-ARDS patients was 2.8%. All patients were male, none had pulmonary co-morbidities and six of them (60%) were on invasive mechanical ventilation. All intubated patients were on lung protective mechanical ventilation. The median PEEP, peak airway pressure and plateau pressure were 10 (IQR: 4), 29 (IQR: 8) and 28 (IQR: 4) respectively. The mean CT severity score was 22.7 (SD: 1.64). Five patients died after 6.8 days (SD: 4.8) of diagnosis. The average hospital stay was of 34 days. CONCLUSIONS: Pneumomediastinum is a possible complication of COVID-Acute respiratory distress syndrome which could signify the disease severity and vice versa. Furthermore, it could be an indicator of relatively poor prognosis and therefore requires larger studies to establish the association.

The Macklin Effect in COVID-19.

From the mere outlook of the ongoing pandemic, coronavirus (severe acute respiratory syndrome coronavirus 2 or SARS-CoV-2) seems to target mainly the respiratory system, but more evolving evidence has advocated its multi-organ involvement. While various complications have been reported in coronavirus disease 2019 (COVID-19) patients, spontaneous pneumomediastinum (SP) remains an uncommon complication.

Spontaneous pneumomediastinum and COVID-19 pneumonia: Report of three cases with emphasis on CT imaging.

Spontaneous pneumomediastinum is a rare complication of coronavirus disease 2019. The published literature consists mainly of case reports and small case series. There are still many questions regarding the pathogenesis, the prognostic significance and the implications on patient management. In our hospital, 3 coronavirus disease 2019 patients developed spontaneous pneumomediastinum: 1 on admission at the emergency department and the other 2 during hospitalization. In this study we describe their clinical course and computed tomography (CT) findings. All of them had severe disease according to the total severity score on admission CT. The management of pneumomediastinum was conservative and follow-up CT showed resolution in all patients. As the correlation between extension of parenchymal lung lesions and development of pneumomediastinum is still under investigation, we highlight the importance of reporting the severity score on chest CT in order to obtain more comparable results between different studies. Furthermore, in this tragic circumstance we also had the opportunity to familiarize ourselves with the otherwise uncommon occurrence of air along the bronchovascular sheaths (Macklin effect) and evaluate the ability of CT to detect it.

Spontaneous pneumomediastinum in COVID-19 patients. Case series.

Spontaneous pneumomediastinum is defined as the presence of free air within the mediastinum without an apparent cause such as chest trauma. It is a benign, self-limiting condition that is conservatively treated. Clinical diagnosis is based on two symptoms: chest pain and dyspnea; and on a particular sign: subcutaneous emphysema. It has been reported in patients with influenza A (H1N1) and severe acute respiratory syndrome; however, it has been rarely observed in COVID-19 patients. In this work, we describe six male patients with COVID-19, aged between 27 and 82 years, who presented with spontaneous pneumomediastinum and subcutaneous emphysema; both conditions were completely resorbed with conservative management.

El neumomediastino espontáneo es la presencia de aire libre en el mediastino sin el antecedente de alguna causa como trauma de tórax. Es una condición benigna autolimitada que se trata en forma conservadora. El diagnóstico clínico se basa en dos síntomas: dolor torácico y disnea; y en un signo en particular: enfisema subcutáneo. Ha sido reportado en pacientes con influenza A (H1N1) y síndrome respiratorio agudo grave; sin embargo, ha sido raramente observado en pacientes con COVID-19. En este trabajo describimos seis pacientes del sexo masculino con COVID-19, con edades entre 27 y 82 años, que presentaron neumomediastino espontáneo y enfisema subcutáneo; ambos se reabsorbieron totalmente con manejo conservador.

Pneumomediastinum in COVID-19 disease: Outcomes and relation to the Macklin effect.

AIM: Pneumomediastinum (PM) is associated with several etiologies and mechanisms. Although it has been described more than 100 years ago, the literature is limited to small retrospective studies. This study aimed to follow patients with coronavirus disease (COVID-19) that developed PM during hospitalization and describe their clinical and radiological evolution. METHODS: A prospective cohort was developed with patients with PM, excluding those with aerodigestive trauma, inside a hospital COVID-19 dedicated hospital. Clinical variables including onset of symptoms, hemodynamic instability, associated complications, the need of interventions, and disease course were all recorded. Also, radiological findings such as the presence of the Macklin effect, extension of lung involvement by COVID-19, and characteristics of the PM were analyzed. RESULTS: Twenty-one patients with non-traumatic PM were followed, resulting in an overall incidence of 0.5% during the study period. Seven (33%) patients had associated pneumothorax and malignant/tension PM was observed in three (14%) cases. The Macklin effect could be found in 11 patients (52%) and the majority of them had more than 50% of lung involvement due to COVID-19. The mortality rate was 49%; however, no deaths were directly related to the PM. CONCLUSIONS: PM incidence is probably increased in the severe acute respiratory syndrome caused by COVID-19, especially in those with greater involvement of the lungs, and the Macklin effect may be an important underlying mechanism of this complication. Usually, PM has a benign course, but complications like tension/malignant PM may occur requiring prompt detection and intervention.

Pneumoperitoneum in a COVID-19 Patient Due to the Macklin Effect.

A 63-year-old male with coronavirus disease 2019 (COVID-19) pneumonia presented to the emergency department, supplementary oxygen is delivered via nasal cannula, and invasive ventilation was not needed; there was significant pneumoperitoneum on radiologic control. After a meticulous examination of the thoracic tomography, there were some linear air collections adjacent to the bronchovascular sheaths, indicative of the Macklin effect, without abdominal alterations, and the patient remained stable; therefore, we did not perform a surgical procedure, and the pneumoperitoneum reabsorbed spontaneously on radiologic control. The pulmonary origin of pneumoperitoneum is unusual and is associated with mechanical ventilation and alveolar leak; the air leak with subsequent dissection into other anatomical spaces is called the Macklin effect. It is essential to have this mechanism in mind because most of these patients respond well to conservative treatment. When studying primary pneumoperitoneum, the cause should be studied carefully to discard visceral perforation, tracheal or esophageal rupture.

Predictors of Pneumothorax/Pneumomediastinum in Mechanically Ventilated COVID-19 Patients.

OBJECTIVE: To determine the incidence, predictors, and outcome of pneumothorax (PNX)/pneumomediastinum (PMD) in coronavirus disease 2019 (COVID-19) acute respiratory distress syndrome (ARDS). DESIGN: Observational study. SETTING: Tertiary-care university hospital. PARTICIPANTS: One hundred sixteen consecutive critically ill, invasively ventilated patients with COVID-19 ARDS. INTERVENTIONS: The authors collected demographic, mechanical ventilation, imaging, laboratory, and outcome data. Primary outcome was the incidence of PNX/PMD. Multiple logistic regression analyses were performed to identify predictors of PNX/PMD. MEASUREMENTS AND MAIN RESULTS: PNX/PMD occurred in a total of 28 patients (24.1%), with 22 patients developing PNX (19.0%) and 13 developing PMD (11.2%). Mean time to development of PNX/PMD was 14 ± 11 days from intubation. The authors found no significant difference in mechanical ventilation parameters between patients who developed PNX/PMD and those who did not. Mechanical ventilation parameters were within recommended limits for protective ventilation in both groups. Ninety-five percent of patients with PNX/PMD had the Macklin effect (linear collections of air contiguous to the bronchovascular sheaths) on a baseline computed tomography scan, and tended to have a higher lung involvement at intensive care unit (ICU) admission (Radiographic Assessment of Lung Edema score 32.2 ± 13.4 v 18.7 ± 9.8 in patients without PNX/PMD, p = 0.08). Time from symptom onset to intubation and time from total bilirubin on day two after ICU admission were the only independent predictors of PNX/PMD. Mortality was 60.7% in patients who developed PNX/PMD versus 38.6% in those who did not (p = 0.04). CONCLUSION: PNX/PMD occurs frequently in COVID-19 patients with ARDS requiring mechanical ventilation, and is associated with increased mortality. Development of PNX/PMD seems to occur despite use of protective mechanical ventilation and has a radiologic predictor sign.