Characteristics and outcomes of reversible platypnoea-orthodeoxia syndrome in COVID-19 pneumonia.

Introduction: Platypnoea-orthodeoxia syndrome (POS) is an uncommon clinical entity characterised by dyspnoea and platypnoea (oxygen desaturation that follows the assumption of an upright position from recumbency). Since the coronavirus disease 2019 (COVID-19) outbreak, increasing reports of COVID-19-related POS and its associated morbidity have been reported around the world. We aimed to study the characteristics of COVID-19-related POS and orthodeoxia (including associations leading to a more prolonged orthodeoxia), and the postdischarge functional outcomes of patients with COVID-19-related POS.

Methods: An observational cohort study was conducted in a tertiary hospital that managed post-COVID-19 patients. Twenty-four participants with severe-to-critical COVID-19 disease/pneumonia and POS, who received inpatient pulmonary rehabilitation, were enrolled. Descriptive analysis of the data was performed to describe POS/orthodeoxia characteristics and functional outcomes in these participants. Correlation analyses were carried out to identify significant factors associated with a prolonged orthodeoxia.

Results: The mean duration of POS and orthodeoxia was 12.9 ± 8.3 days and 28.5 ± 14.6 days, respectively. All participants demonstrated resolution of POS and orthodeoxia by hospital discharge. On multivariable analysis, intensive care unit admission and maximal level of respiratory support were significantly associated with a prolonged duration of orthodeoxia. One participant was lost to follow-up. The remaining 23 participants achieved independence in self-care. With the exception of one patient, who was recovering from a hip fracture, the rest achieved independence in ambulation and independent community access.

Conclusion: Resolution of orthodeoxia was observed in all our participants with COVID-19-related POS. Good functional outcome can be attained with timely and effective rehabilitation interventions.