The most common complications in COVID-19 infections are bilateral pneumonia which may progressed to ARDS, complications are more in serious sickness versus non-extreme illness [4].
Positive pressure ventilation is a non-physiological and invasive intervention that can be lifesaving in COVID-19 patients. Similar to any other interventions, it can cause its own danger and complications as it can prompt ventilator-induced lung injury and barotrauma [5].
In this study, we detected a high incidence of barotrauma in patients with coronavirus 2019 infection receiving invasive mechanical ventilation at our isolated hospital during the peak of the COVID-19 pandemic, with a per-total patient admission rate of 16.8%. Udi1 J. et al. [9] reported a rate of barotrauma of 40% in a mixed collective of invasive ventilated COVID-19 patients.
Most patients on IMV had at least daily films, but varying intervals between films in this retrospective study could theoretically confound our assessment of single versus separate multiple events.
These high barotrauma rates raise questions of whether coronavirus infections uniquely increase barotrauma risk. At first, it was widely supposed that respiratory failure in COVID-19 infection patients was due to viral pneumonitis progressed to ARDS; thus, many severely ill patients were mechanically ventilated with high positive end-expiratory pressure.
Mechanical ventilation can lead to expansion and increased pressures in the alveoli units leading to inflammatory changes and possibly rupture and spillage of air into the extra-alveolar tissue that can manifest as pneumothorax, pneumomediastinum, pneumoperitoneum, and subcutaneous emphysema [5].
Our observed high rate of barotrauma in COVID-19 patients on IMV may support emerging theories of lung damage in SARS-CoV-2 infection.
Fifty-five patients had either a unilateral or bilateral pneumothoraces, for an overall pneumothorax rate of 55 of 103 (53.4%), McGuinness G. et al., [7], observed overall pneumothorax rate of 54 of 601 (9%). While in reported small study, a pneumothorax rate was 30% in intensive care unit–intubated patients [10].
In the retrospective single-center study observed by Chen et al. [11] including 99 a total of patients with COVID-19 pneumonia, pneumothorax occurred only in 1 patient.
The management of most simple pneumothorax in mechanically ventilated patients involved the placement of a thoracostomy tube to evacuate the air.
In patients with clinically significant pneumothorax, would present with acute vital signs changes, including hypoxia, tachypnea, and tachycardia. Patients may also progress to tension pneumothorax [6]. In patients with tension pneumothorax, management is essential before obtaining a chest radiograph, which requires urgent needle decompression to relieve the pneumothorax, followed by thoracotomy tube placement. In patients presented with a less critical complication, such as a simple pneumothorax with stable vital signs, pneumomediastinum, or subcutaneous emphysema, the clinician should obtain a chest radiograph immediately [6].
Twenty-eight of the 103 patients (27.2%) had pneumomediastinum, while in McGuinness G. et al. [7], represented 10%. As pneumomediastinum is caused by an increase in intra-alveolar pressure, produced alveolar rupture, and air migrates that dissects the peribronchial and perivascular sheaths of the pulmonary hilum (Maclin effect) [12].
Although the smoking represents a risk factor for barotrauma, the majority of intubated barotrauma patients with COVID-19 in our study were never smokers, our result agreed with McGuinness G. et al. [7] observation.
In China high smoking rates were initially thought to pool to severe morbidity in early reports of COVID-19 infection; however, in our institution, smoking was not associated with an increased risk of hospitalization or critical illness [13].
In our study, COVID-19 infectious patients with barotraumas were old, suggesting an age-related risk for barotrauma. Our observation was older age in COVID-19 patients after IMV was an independent risk factor for barotrauma. This observation did not agree with Petersen GW [14] study, younger age has been related to barotrauma in patients in the intensive care unit, and barotrauma in McGuinness et al. [7], cohort study was less likely to occur in older patients.
Actually, multinomial regression analysis showed that older patient with barotrauma, is associated with higher mortality.
Our registry detected specific disease conditions; including interstitial lung disease (ILD), chronic obstructive pulmonary disease (COPD), pneumonia, asthma, and acute respiratory distress syndrome (ARDS) represented 50/103 (48.5%) were associated with higher incidence of pulmonary barotrauma. These diseases are concomitant with either poor lung compliance or dynamic hyperinflation, both of which lean patients to elevated alveolar pressure and therefore barotrauma [15].
Patients who develop barotrauma secondary to mechanical ventilation also end up staying in the ICU and on mechanical ventilation for a more broadened period. Longer time on mechanical ventilation may result in additional complications secondary to barotrauma as well as others, including ventilator-associated pneumonia, delirium, intensive care acquired weakness, and nosocomial infections [16].
Whereas, our survival rate from patients with barotrauma was 20.5%, indicating that in most cases barotrauma were severe, complicated and could not successfully be managed and was an inevitable cause of death in our cohort of patients, while Udi et al. [9] study showed survival rate was 75%.
At the end of our period, 13.6% COVID-19 patients with barotrauma remained hospitalized, while represented 30% in McGuinness et al. [7], cohort study and it was not clear whether barotrauma caused prolonged hospitalization or longer hospital stay was a risk for barotrauma.
Breathing natural mechanism in humans depends upon negative intra-thoracic pressures. In contrast, mechanically ventilate patients are on with positive pressures. Since positive pressure ventilation is not physiological, it may raise the occurrence of barotrauma [17].
There were few limitations in this study: a small number of the patient population, the study was single-center retrospective study, pathologic correlation was not available for many included patients.
We focused on chest X-ray and CT chest findings and did not investigate a possible association between barotrauma and respirator settings. Since optimum characterization and detection of barotraumas frequently require computed tomography, the findings might be under diagnosed if only less sensitive chest radiography is obtained.