3 DISCUSSION
Bilateral pneumothorax due to COVID-19 has not been widely reported in
the literature so far. The pathophysiology for the development of
pneumothorax in patients with COVID-19 is unclear; however, cystic and
fibrotic structural changes caused by COVID-19 may be
related4. In addition to this, treatment with positive
pressure by non-invasive or mechanical ventilation in patients with
severe COVID-19 infection may contribute to the development of
pneumothorax5. Systemic corticosteroids exhibit
anti-inflammatory and anti-fibrotic effects in patients with severe
COVID-19 infection. However, corticosteroid therapy may also cause a
delay in the wound healing process of pneumothorax6.
There is no established treatment strategy for secondary spontaneous
pneumothorax due to COVID-19. Surgical intervention presents a better
outcome than tube thoracostomy in simultaneous bilateral primary
spontaneous pneumothorax7. However, in some patients
surgical intervention for pneumothorax may pose high risk from the
perspective of general and respiratory condition. In patients with poor
general condition and who are not fit for surgery, refractory
pneumothorax must be cured by other internal therapies. Internal
treatments for pneumothorax include procedures such as chest drainage,
pleurodesis, endobronchial approach8. In some cases,
it is important to combine multiple methods. We decided that our
patient’s general condition was not good enough to operate. Thus, the
combination bronchial occlusion and pleurodesis relieved the patient’s
bilateral refractory pneumothorax. Bronchial occlusion using an
EWS® is one of the most effective and minimally
invasive treatments for secondary refractory pneumothorax, postoperative
pulmonary fistula, fistulous empyema, and bronchial fistula in patients
with poor general condition. Bronchial occlusion alone or in combination
with pleurodesis for secondary refractory pneumothorax, postoperative
pulmonary fistula, or fistulous empyema enabled drain removal in 57.1%
to 86.0% of patients9-11.
Mitsuyama et al. reported that autologous blood patch pleurodesis may be
a treatment option for recurrent and refractory pneumothorax secondary
to COVID-1912. In our case, pleurodesis with MINO and
OK-432 was ineffective, whereas the one with autologous blood was
effective. Pleurodesis with autologous blood has fewer side effects than
that with other drugs such as OK-432, talc, glucose and minocycline
hydrochloride13 Therefore, pleurodesis with autologous
blood is a better strategy for refractory pneumothorax in patients with
poor general condition after severe COVID-19 infection. In case of
inoperable patients with refractory pneumothorax after severe COVID-19
infection, bronchial occlusion and pleurodesis can be key treatment
strategies.