Article, Pulmonology

A breath of fresh air: The role of incentive spirometry in the treatment of COVID-19

Dear Editor:

With over 93 million cases of the coronavirus disease of 2019 (COVID-19) worldwide, clinicians continue to search for new treatment options to reduce its morbidity and mortality. While 80-90% of COVID-19 patients are asymptomatic or have only mild symptoms, some develop severe pulmonary complications, including Acute Respi- ratory Distress Syndrome (ARDS) [1]. Among those who develop ARDS, there is a high mortality rate. Factors causing some patients to progress from mild to severe symptoms have not been fully elucidated, but the change can occur quickly, with an average of 8 days between first symptom and ARDS onset [1]. This period presents a time where in- tervention may be able to prevent Clinical worsening. Unlike in severe COVID-19 cases, providers have very few treatment options to offer pa- tients with mild-to-moderate symptoms in order to prevent progres- sion to severe disease. We propose that incentive spirometry (IS) be considered an intervention to treat patients with mild-to-moderate COVID-19 disease.

Incentive spirometry is a lung expansion technique used to promote sustained maximal inspiration, which is proposed to help patients by improving ventilation/perfusion mismatch and alveolar-PaO2 gradient. These effects reduce intrapulmonary shunting and the risk of atelectasis [2]. Incentive spirometry is commonly used for pre- and post-operative patients, as well as patients with pneumonia, Acute chest syndrome, COPD exacerbations, and ARDS [2].

Patients with COVID-19-related ARDS (CARDS) demonstrate a phe- notype of ARDS with preserved lung compliance. Although initially thought to represent a novel phenotype, a re-analysis of the LUNG SAFE data by de Prost and colleagues suggested that ARDS with pre- served lung compliance were prevalent pre-COVID-19 [3]. Since both ARDS phenotypes involve decreased PaO2:FiO2 ratio as a result of intrapulmonary shunting, it is not surprising that placing patients in a prone position leads to improved oxygenation in both CARDS and non-COVID-ARDS [4]. The benefit of proning results from decreased ventilation/perfusion mismatch by recruiting more alveoli to open from previously compressed areas of the lung [4]. Incentive spirometry works similarly by decreasing ventilation/perfusion mismatch via splinting and preventing alveolar collapse [1].

Although some hospitals include IS in their discharge instructions for patients with COVID-19, it is not a universally-accepted recommenda- tion. Early in the pandemic, concerns were raised that IS may lead to self-inflicted lung injury [5]. However, there are no data to our knowl- edge demonstrating lung injury resulting from IS, and IS has been suc- cessfully used in a variety of other pulmonary illnesses without leading to significant lung injury [2]. Another concern was that IS

the role of IS in the management of COVID-19 so that clinicians may bet- ter treat these patients as well as apply the findings to future pandemics.

Funding

None.

Author contributions

JC conceived the presented ideas. HS performed a literature review and drafted the letter. JC, MG, and HS edited and revised the document before giving final approval for submission.

References

  1. Navas-Blanco JR, Dudaryk R. Management of respiratory distress syndrome due to COVID-19 infection. BMC Anesthesiol. 2020;20(1):177 Published 2020 Jul 20 https://doi.org/10.1186/s12871-020-01095-7.
  2. Eltorai AEM, Szabo AL, Antoci Jr V, et al. Clinical effectiveness of incentive spirometry for the prevention of postoperative pulmonary complications. Respir Care. 2018;63 (3):347-52.
  3. de Prost N, Pham T, Carteaux G, et al. Etiologies, diagnostic work-up and outcomes of acute respiratory distress syndrome with no common risk factor: a prospective mul- ticenter study. Ann Intensive Care. 2017;7(1):69.
  4. Sarma A, Calfee CS. Prone positioning in awake, Nonintubated patients with COVID- 19: Necessity is the mother of invention [published online ahead of print, 2020 Jun 17]. JAMA Intern Med. 2020; https://doi.org/10.1001/jamainternmed.2020.3027.
  5. Sheehy LM. Considerations for postacute rehabilitation for survivors of COVID-19. JMIR Public Health Surveill. 2020;6(2):e19462.

Hannah Seyller

University of Illinois at Chicago, College of Medicine, Chicago, IL, USA

?Corresponding author.

E-mail address: [email protected]

Michael Gottlieb

Department of Emergency Medicine, Rush University Medical Center,

Chicago, IL, USA

Joseph Colla

Department of Emergency Medicine, University of Illinois at Chicago,

Chicago, IL, USA

27 January 2021

https://doi.org/10.1016/j.ajem.2021.01.084

0735-6757/(C) 2021