Incidence and Outcome of Pneumomediastinum in Non-ICU Hospitalized COVID-19 Patients

Pneumomediastinum in COVID-19: Risk Factors and Outcomes from a Multicentre Case-control Study

BACKGROUND

An increased incidence of pneumomediastinum has been observed among patients hospitalized with coronavirus disease 2019 (COVID-19) pneumonia. The study aimed to identify risk factors for COVID-19-associated pneumomediastinum and investigate the impact of pneumomediastinum on clinical outcomes.

METHODS

In this multicentre retrospective case-control study, we included consecutive patients with COVID-19 pneumonia and pneumomediastinum hospitalized from March 2020 to July 2020 at ten centres; then, we identified a similarly sized control group of consecutive patients hospitalized with COVID-19 pneumonia and respiratory failure who did not develop pneumomediastinum during the same period. Clinical, laboratory, and radiological characteristics, as well as respiratory support and outcomes, were collected and compared between the two groups. Risk factors of pneumomediastinum were assessed by multivariable logistic analysis.

RESULTS

Overall 139 patients with pneumomediastinum and 153 without pneumomediastinum were analysed. Lung involvement ≥75%, consolidations, body mass index (BMI) <22 kg/m2, C-reactive protein (CRP) >150 mg/L, D-dimer >3000 ng/mL FEUs, and smoking exposure >20 pack-year were all independently correlated with the occurrence of pneumomediastinum. Patients with pneumomediastinum had a longer hospital stay (mean ± SD 31.2 ± 20.2 days vs 19.6 ± 14.2, p<0.001), higher intubation rate (73/139, 52.5% vs 27/153, 17.6%, p <0.001), and in-hospital mortality (68/139, 48.9% vs 36/153, 23.5%, p <0.001) compared to controls.

CONCLUSIONS

Extensive lung parenchyma involvement, consolidations, low BMI, high inflammatory markers, and tobacco exposure are associated with a greater risk of pneumomediastinum in COVID-19 pneumonia. This complication significantly worsens the outcomes.

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.

Barotrauma during Noninvasive Respiratory Support in COVID-19 Pneumonia Outside ICU: The Ancillary COVIMIX-2 Study

BACKGROUND

Noninvasive respiratory support (NIRS) has been extensively used during the COVID-19 surge for patients with acute respiratory failure. However, little data are available about barotrauma during NIRS in patients treated outside the intensive care unit (ICU) setting.

METHODS

COVIMIX-2 was an ancillary analysis of the previous COVIMIX study, a large multicenter observational work investigating the frequencies of barotrauma (i.e., pneumothorax and pneumomediastinum) in adult patients with COVID-19 interstitial pneumonia. Only patients treated with NIRS outside the ICU were considered. Baseline characteristics, clinical and radiological disease severity, type of ventilatory support used, blood tests and mortality were recorded.

RESULTS

In all, 179 patients were included, 60 of them with barotrauma. They were older and had lower BMI than controls (p < 0.001 and p = 0.045, respectively). Cases had higher respiratory rates and lower PaO₂/FiO₂ (p = 0.009 and p < 0.001). The frequency of barotrauma was 0.3% [0.1-1.3%], with older age being a risk factor for barotrauma (OR 1.06, p = 0.015). Alveolar-arterial gradient (A-a) DO₂ was protective against barotrauma (OR 0.92 [0.87-0.99], p = 0.026). Barotrauma required active treatment, with drainage, in only a minority of cases. The type of NIRS was not explicitly related to the development of barotrauma. Still, an escalation of respiratory support from conventional oxygen therapy, high flow nasal cannula to noninvasive respiratory mask was predictive for in-hospital death (OR 15.51, p = 0.001).

CONCLUSIONS

COVIMIX-2 showed a low frequency for barotrauma, around 0.3%. The type of NIRS used seems not to increase this risk. Patients with barotrauma were older, with more severe systemic disease, and showed increased mortality.