Clinical Effect of Pulmonary Rehabilitation on Patients with Severe or Critically Severe COVID 19 Pneumonia

Background: The rapid spreading of coronavirus disease 2019 (COVID-19) is an emerging threat to the global public health. Optimal treatment for severe COVID-19 pneumonia is extremely urgent. We conducted this study to evaluate the safety, feasibility and effect of pulmonary rehabilitation (PR) intervention in the treatment of patients with severe or critically severe COVID-19 pneumonia. Methods: In this retrospective study, 43 patients with severe or critically severe COVID-19 pneumonia were included and divided into conserved intervention group (C-I group) and advanced intervention group (A-I group) according to the initiation time of PR intervention. The PR intervention includes education, respiratory rehabilitation, physical training, psychological counseling and nutrition management. Oxygenation Index (OI), blood d-dimer level, lymphocyte count and other laboratory findings were recorded. Findings: The median age of 43 patients was 54 years (range 21 to 75 years); of them, 11 (25.6%) were 65 or older. 24 (55.8%) were male. All patients safely finished a certain course of pulmonary rehabilitation training. The OI could increase to moderate level (>300mmHg) during ICU treatment, and the A-I group showed a faster trend. The time of OI increased to moderate level was significantly shorter than that in C-I group (p=0.02). Lymphocytopenia occurred in 35 patients. The time of lymphocytopenia recovery was shorter in A-I group than that in C-I group. 25 patients had elevated blood d-dimer level during ICU stay. Only one DVT case was found in C-I group by ultrasound examination, no significant differences were found. Interpretation: With good safety and feasibility, pulmonary rehabilitation intervention can bring benefits in the treatment of patients with severe or critically severe COVID-19 pneumonia. Funding Statement: This study was funded by the Emergency Project of Prevention and Control for COVID-19 of Central South University, No. 502701002. Declaration of Interests: The authors declare no conflict of interest. Ethics Approval Statement: The study protocol was approved by the institutional ethics committee of the First Hospital of Changsha (KL-2020005) and the Second Xiangya Hospital of Central South University (2020-010), and informed consent was waived because of the retrospective design.