Pneumothorax and pneumomediastinum in patients hospitalized with coronavirus disease 2019 (COVID-19).

Dear Editor,

Spontaneous Pneumothorax (PTX) has received increasing attention as a complication of Coronavirus disease 2019 (COVID-19). , In the January article, Ekanem et al. identified PTX in 1.4% of 1619 COVID-19 who had no evidence of trauma during hospitalization. Here, we describe our tertiary care center's experience with spontaneous PTX and pneumomediastinum (PTM) among patients hospitalized from March to October 2020 with laboratory confirmed COVID-19 in suburban New York. PTX and/or PTM cases were categorized as either spontaneous (primary or secondary) or as other events (present in close temporal association with trauma or a medical procedure) using prior definitions. Outcomes were PTX/PTM events, radiological resolution, recurrence, and overall mortality. During the study period, PTX and/or PTM was documented in 25/1260 (2%) of all hospitalized adult patients with COVID-19.

Ten of twenty-five patients had spontaneous PTX, 1/25 had spontaneous PTM and 7/25 had spontaneous PTX and PTM. In the remaining 7/25 patients, PTX/PTM occurred in close temporal relation to: a medical procedure (3/7), blunt trauma (2/7), a stab wound to the chest (1/7) and intubation (1/7). The mean duration from COVID-19 symptoms to PTX/PTM was 16 (0–46) days. Mechanical ventilation preceded PTX/PTM in 18/25 (72%) of patients by a mean of 9 (0–33) days. A low tidal volume ventilation strategy (4–8 mL/kg) was utilized for all except one study patient. Of the study patients, 52% died (13/25) at a mean of 17 (0–61) days after PTX/PTM. Two patients died shortly after development of tension PTX. The mean duration of hospital stay was 31 (2–104) days. Further details are available in the Table 1 .

Table 1

Clinical Course and Charactersitics of Patients Hospitalized with COVID-19 and Pneumothorax and/or Pneumomediastinum

Characteristics of Patients	Number, Percent
Patients Hospitalized with COVID-19 (March 2020 – October 2020)	Total n = 1260
Pneumothorax / Pneumomediastinum
Total events	25/1260 (1.98%)
Spontaneous events	18/1260 = (1.4%)
Hospital Course
All-Cause Mortality	13/25 (52%)
Length of Stay; (mean/days, range)	31 (2–104)
Demographics
Age (mean/years)	55 (23–83)
Sex (Male)	19/25 (76%)
Body Mass Index (Mean, range)	30 (20–48)
Chronic Medical Conditions
None	8/25 (32%)
Cardiovascular Disease	7/25 (28%)
Chronic Lung Disease	1/25 (4%)
Imaging Findings at Presentation
Clear Chest X-ray or Computed Tomography	2/25 (8%)
Bilateral Airspace Opacities	17/25 (68%)
Chronic lung disease	1/25 (4%)
Events and Type
Type of Event
Spontaneous PTX	10/25 (40%)
Spontaneous PTM	1/25 (4%)
Spontaneous PTX and PTM	7/25 (28%)
Other (Events with Preceding Factors)	7/25 (28%)
Medical procedure(s)	3/7 (43%)
Intubation	1/7 (14%)
Blunt Trauma	2/7 (29%)
Sharp Trauma	1/7 (14%)
Management
Chest Tube	15/25 (60%)
Resolution	21/25 (84%)
Recurrence	7/23 (30%)

This study adds importantly to the growing literature describing pulmonary complications of COVID-19. In our cohort, the overall rate of spontaneous PTX and/or PTM was 1.4% with the majority of patients being male (76%) and having no prior history of lung disease. These findings are remarkably consistent with those of Ekanum et al., who documented a spontaneous PTX rate of 1.4% with a strong male predominance. In addition, we found that PTX/PTM reoccurred in around one-third of patients. The overall mortality in this cohort was 52%, while mortality was 36% in Ekanum. However, their study concluded with 4 patients remaining on mechanical ventilation or extracorporeal membrane oxygenation.

The work of Ekanum et al. and our findings indicate that COVID-19 patients are at potential risk for the development of PTX/PTM through a variety of mechanisms. Histological findings from lung tissue in patients with COVID-19 include alveolar damage with septa disruption, desquamation, edema, and exudates with fibrotic/thickened interstitial tissue. This tissue damage along with other inflammatory sequelae of COVID-19 likely permits air entry into the pleural and/or mediastinal spaces causing PTX/PTM and also sets the stage for potential recurrence. In addition, COVID-19 patients frequently require mechanical ventilation and/or invasive procedures/interventions under challenging circumstances. In Ekanum, 41% of patients were on mechanical ventilation when PTX developed and in our cohort mechanical ventilation preceded PTX/PTM in nearly three-fourths of patients.

Care of critically patients with COVID-19 is uniquely challenging due to reduced direct patient/provider contact and difficulties in transporting patients for procedures/tests. These factors may contribute to higher than usual risks of procedural complications or delays in diagnosis. Furthermore, a sudden deterioration in respiratory status of the mechanically ventilated COVID-19 patient could be attributed to progression of viral disease, pulmonary embolism, aspiration event, new or worsening ARDS or secondary bacterial infection in addition to PTX/PTM. As such, diagnosis of PTX and PTM in these patients requires a high index of clinical suspicion. Future studies designed to identify more effective ways to prevent PTX and PTM in hospitalized patients with COVID-19 are warranted.