Archives of Academic Emergency Medicine. 2022; 10(1): e45 OR I G I N A L RE S E A RC H The Effect of Exercise-Based Pulmonary Rehabilitation on Quality of Life in Recovered COVID-19 Patients; a Quasi- Experimental Study Seyed Mansoor Rayegani1, Rama Bozorgmehr2, Leila Angooti Oshnari3∗, Amir Hossein Mahdi Kaghazi4 1. Physical Medicine and Rehabilitation Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran. 2. Clinical Research Development Unit, Shohada-e Tajrish Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran. 3. Physical Medicine and Rehabilitation Research Center, Occupational Therapy Department, Shohada-e-Tajrish Hospital, Shahid Beheshti University of Medical Science, Tehran, Iran. 4. Physical Medicine and Rehabilitation Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran. Received: March 2022; Accepted: May 2022; Published online: 8 June 2022 Abstract: Introduction: The coronavirus disease 2019 (COVID-19) is associated with a variety of physical and emotional disorders, and subsequently lower Quality of Life (QOL). This study aimed to investigate the effect of a 2-week exercise-based pulmonary rehabilitation on clinical characteristics and QOL of severe COVID-19 patients after discharge from intensive care unit (ICU). Methods: In this quasi-experimental study, eligible severe COVID-19 cases, who had survived and were discharged from ICU were selected using convenience sampling method. Oxygen Saturation ( SpO2), pulse rate, dyspnea, and QOL were evaluated and compared before and after two weeks of exercise-based pulmonary rehabilitation (PR). Results: 35 cases with the mean age of 57.86 ± 11.73 (18-75) years were studied (51.4% female). The mean SpO2 increased from 90.41 ± 3.97 to 95.11 ± 1.96% after two weeks of pulmonary rehabilitation (p<0.0001). In addition, the mean pulse rate (98.97±16.23 to 88.91±14.03 pulse/minute; p<0.001) and the mean dyspnea severity (5.6±1.97 to 3.45±1.97; p<0.0001) decreased after two weeks of intervention. Besides, the mean total QOL and its dimensions, including general health (p<0.0001), physical status (p<0.0001), emotional status (p = 0.036), and social function (p<0.0001) of patients, had signif- icantly increased after intervention. Conclusion: Based on the findings of this study, it seems that two-week exercise-based pulmonary rehabilitation could be effective in increasing the SpO2, decreasing dyspnea and pulse rate, and improving the QOL of patients with severe COVID-19 after discharge from ICU. Keywords: COVID-19; Exercise Therapy; Lung; Rehabilitation; Quality of Life Cite this article as: Rayegani SM, Bozorgmehr R, Angooti Oshnari L, Mahdi Kaghazi AH. The Effect of Exercise-Based Pulmonary Re- habilitation on Quality of Life in Recovered COVID-19 Patients; a Quasi-Experimental Study. Arch Acad Emerg Med. 2022; 10(1): e45. https://doi.org/10.22037/aaem.v10i1.1569. 1. Introduction The coronavirus disease 2019 (COVID-19) appeared in Wuhan, China in December 2019, and three months later, the World Health Organization declared it a pandemic. At that time, Iran was ranked the third most-affected country in the world. Patients diagnosed with COVID-19 may ex- ∗Corresponding Author: Leila Angooti Oshnari; Occupational Therapy Unit, Department of Physical Medicine and Rehabilitation, Shohada-e-Tajrish Hos- pital, Shohada-e-Tajrish Hospital, Tajrish Sq., Tehran, Iran. Postal Code: 1989934148 Email: leylaa1768@yahoo.com, Tel: +989125046923, ORCID: http://orcid.org/0000-0001-6059-5892. perience a wide range of clinical manifestations, which are categorized into no symptoms, mild, moderate, severe, and critical symptoms. Fever, dry cough, sore throat, restless- ness, muscle and joint pain, nasal congestion, sneezing and running nose, respiratory failure, general systemic dysfunc- tion, and acute respiratory syndrome are some of the known signs and syndromes related to COVID-19 (1-6). It proves that treatment and outcomes of COVID-19 depend on the disease severity (4). Outpatients diagnosed with COVID-19 may ex- perience symptoms for more than four weeks, which is called long COVID-19 (7). Fatigue, dyspnea, muscle pain, weakness, and psychological distress are the most common symptoms in patients with long COVID-19 (6, 7). A vast range of physi- This open-access article distributed under the terms of the Creative Commons Attribution NonCommercial 3.0 License (CC BY-NC 3.0). Downloaded from: http://journals.sbmu.ac.ir/aaem SM. Rayegani et al. 2 cal and psychological disorders, along with decreased quality of life (QOL), are associated with SARS-CoV-2 infection (4, 7- 10). Based on previous studies and guidelines, rehabilitation pro- grams would be effective for patients diagnosed with COVID- 19, especially in patients who were hospitalized (2, 5, 11, 12). All these programs, including aerobic exercises, strengthen- ing, and stretching exercises of respiratory muscles may im- prove cardiorespiratory tolerance and physical function of patients, as well as their quality of life (13). In addition, res- piratory exercises, such as diaphragmatic, bud lip, and resis- tance breathing will help in reducing active coughing in such patients (2, 14). This study aimed to investigate the effect of a 2-weeks exercise-based pulmonary rehabilitation on clini- cal characteristics and QOL of severe COVID-19 patients after discharge from intensive care unit (ICU). 2. Methods 2.1. Study design and setting This quasi-experimental study with before-after design, was performed on severe COVID-19 cases, who had survived and were discharged from intensive care unit of Shohada- e-Tajrish Hospital, Tehran, Iran, during 2021. O2 saturation ( SpO2), pulse rate, dyspnea, and QOL were evaluated and compared before and after two weeks of pulmonary rehabil- itation (PR) in enrolled patients. The study protocol was approved by the Ethics Committee of Shahid Beheshti University of Medical Sciences (Ethics code: IR.SBMU.RETECH.REC.1400.531) and also registered in Ira- nian Registry of Clinical Trials (IRCT20211201053238N1). Written informed consent forms were signed to participate in the research. Personal information was kept confidential and patients were given an identification code in the ques- tionnaire form, instead of mentioning their name. 2.2. Participants Being aged between 18 and 75 years, recovered from severe COVID-19, hospitalized to ICU (between 3 to 18 weeks), sat- isfied to participate in the research, and referred to the de- partment of physical medicine and rehabilitation by pulmo- nologist and intensive care specialist due to respiratory fail- ure, as well as not receiving any PR before the study were among the inclusion criteria. Patients who had problems with pulmonary massage, including active wounds, fractures and skin disorders in the chest area (15), a history of un- controlled cardiovascular problems, chronic obstructive pul- monary disease (COPD), renal, neurological, and cognitive problems, acute rheumatic diseases, hypertension, hemopt- ysis, psychology disorder, and cancer which lead to not being able to do exercises were excluded. 2.3. Data gathering The data regarding demographic characteristics, SpO2, pulse rate, dyspnea, and QOL were collected for all patients before and after two weeks of pulmonary rehabilitation by trained occupational therapist in Physical Medicine and Rehabilita- tion clinic. Measurements of SpO2 and pulse rate was done using pulse oximeter (ChoiceMed made in China (with Coef- ficient of Variation (CV ): 0.01)). The level of dyspnea was cal- culated using valid and reliable Modified Borg scale, which is subjective and rated by the patient from one up to 10 (16). The QOL was measured using SF-36 questionnaire, which has been proven reliable and valid for Iranians by Montaz- eri with Intra Class Reliability and Coefficients: <0.05 (17). Generally, SF-36 questionnaire investigates the patient in 8 areas (physical status, physical role, body pain, emotional status, emotional role, social function status, fatigue, general health), and consists of eleven parts and 36 multiple choice questions. In this study, general QOL and its’ 4 dimensions, including physical status (physical status, physical role, body pain, fatigue), emotional status (emotional status, emotional role), general health, and social function were evaluated. 2.4. Intervention PR included training to stay in one of 5 sitting or standing comfortable positions and getting head and shoulders down and breathe in and blow out at first through the mouth and after that doing diaphragmatic breathing for 5 minutes to ease shortness of breath, getting lung massages (with cup- ping and vibratory techniques) (18) and doing 10 kinds of ex- ercises. The exercises consisted of 3 respiratory exercises, in- cluding pursed lip in diaphragmatic, shoulder shrugging and rib breathing, 2 upper extremity exercises, reaching arms to the sky and elbows touch, and 5 lower limbs exercises, in- cluding hip hiking, knee abduction/adduction in crock lying, foot rocking in sitting, stepping, and squatting in standing position (18, 19) with 10 repeat, in two face to face sessions in the first week (Sundays and Tuesdays for 60 minutes) and the follow up during all the second week. All the enrolled pa- tients were followed up for two weeks. 2.5. Statistical analysis The study sample size was calculated as 35 based on two vari- ables; SpO2 and QOL, with 95% confidence interval, Power = 80%, and d=0.02 (19). After data gathering and coding, anal- ysis of variances with Wilcoxon and repeated measurement were used to analyze the data in 26-SPSS. SpO2, dyspnea, and emotional status and social function of QOL did not have normal distribution and the Wilcoxon method was used in- stead of paired t-test. The findings were reported as mean ± standard deviation or frequency (%). P < 0.05 was considered as level of significance. This open-access article distributed under the terms of the Creative Commons Attribution NonCommercial 3.0 License (CC BY-NC 3.0). Downloaded from: http://journals.sbmu.ac.ir/aaem 3 Archives of Academic Emergency Medicine. 2022; 10(1): e45 Table 1: Baseline characteristics of studied patients Variable Value Gender Female 18 (51.4) Male 17 (48.6) Start of disease to the initial assessment (days) 21-56 18 (51.4) 57-91 14 (40.0) 92-126 3 (8.6) Marital Status Single 4 (11.4) Married 22 (62.9) Widowed/Divorced 9 (25.7) Education Illiterate 4 (11.4) Primary school 14 (40.0) High school 11 (31.4) University 6 (17.1) Job Housewife/none 23 (65.7) Employed 12 (34.3) Data are presented as frequency (%). 3. Results 3.1. Baseline characteristics of patients 35 cases with the mean age of 57.86 ± 11.73 (18-75) years were studied (51.4% female). The mean Body Mass Index (BMI) of studied cases was 23.31 ± 3.36 kg/m2 and the mean time interval between the start of disease to the initial assessment in hospital was 56.01 ± 25.06 days. Baseline characteristics of patients are presented in table 1. 3.2. Outcomes of Interventions The mean SpO2 increased from 90.41 ± 3.97 to 95.11 ± 1.96% after two weeks of pulmonary rehabilitation (p<0.0001). In addition, the mean pulse rate (98.97±16.23 to 88.91±14.03; p<0.001) and the mean dyspnea severity (5.6±1.97 to 3.45±1.97; p<0.0001) decreased after two weeks of interven- tion. Besides, the mean total QOL and its dimensions, including general health (p<0.0001), physical status (p<0.0001), emo- tional status (p = 0.036), and social function (p < 0.0001) of patients had significantly increased after intervention. Ta- ble 2 compares the measured outcomes before and after two weeks of pulmonary rehabilitation in studied cases. 4. Discussion Based on the findings of this study, it seems that two-week exercise-based pulmonary rehabilitation could be effective in increasing the O2 saturation, decreasing dyspnea and pulse rate, and improving the QOL of severe COVID-19 pa- tients after discharge from intensive care unit. Restrictive pulmonary changes and reduced diffusion capac- ity in patients diagnosed with moderate to severe COVID-19 may lead to long-term functional limitations, as well as re- duced QOL in such patients. Considering the previous stud- ies, it appears that pulmonary rehabilitations may be help- ful for patients diagnosed with acute respiratory distress syn- drome as a consequence of COVID-19 (15, 21-23). Overall, beneficial impacts of rehabilitation have been clearly exhib- ited in a wide range of health conditions, and in patients with pulmonary diseases such as COPD, rehabilitation re- duces dyspnea and improves health-related quality of life (24). Since short-term benefits have been reported for PR by patients, to ensure long-term effects, maintenance of physi- cal activity and healthy lifestyles should be enforced by pro- viding personalized home-based rehabilitation programs or referring the patients to long-term rehabilitation outpatient centers with an integrated model of care (6). A variety of studies revealed that pulmonary rehabilitation improved the SpO2 in patients who survived COVID-19 (5, 18, 19, 25, 26). The present study results were consistent with the mentioned studies. In this study, like the Huang (27) and McGregor (28) studies, the mean pulse rate significantly de- creased after rehabilitation programs. Also, the average pulse rate reduced, in line with the stud- ies by Alahmri (21) and Huang et al. (2004), which showed that the patients recovered pulse rate after rehabilitation (27). Additionally, in this study, the average of dyspnea reduced, which was in line with Huang (27) and McGregor et al.’s find- ings (28). This improvement was probably not only related to PR but also to the natural recovery process of the disease (29). Moreover, in terms of quality of life, a significant increase was reported in patients enrolled in the study after two weeks of the exercise-based pulmonary rehabilitation. Like the present study, recent studies demonstrated that pulmonary rehabilitation may improve the quality of life in patients di- agnosed with COVID-19 (19, 28, 30). A study conducted by McGregor revealed that pulmonary rehabilitation could im- prove the general health status of patients with COVID-19 (28). In the present study, exercise-based pulmonary reha- bilitation improved the general health status of enrolled pa- tients, as well as other sub-domains of QOL questionnaire. In recent studies, physical status, emotional status, and social function of patients were improved in patients who under- went pulmonary rehabilitation (24, 28, 30, 31). Severe COVID-19 cases required prolonged ICU stay and in- tubation; therefore, they had more physical and psychosocial impairments post-ICU, but recovered following PR. Further controlled and long-term studies are required to better un- derstand the role of PR post-COVID-19 (29). Unfortunately, in this study we faced some restrictions. The This open-access article distributed under the terms of the Creative Commons Attribution NonCommercial 3.0 License (CC BY-NC 3.0). Downloaded from: http://journals.sbmu.ac.ir/aaem SM. Rayegani et al. 4 Table 2: Comparing the status of studied variables before and after two weeks of exercise-based pulmonary rehabilitation Variable Mean ± SD P value SpO2 (%) Before 90.71 ± 3.97 <0.0001 After 95.11 ± 1.96 Pulse Rate (/minutes) Before 98.97 ± 16.23 <0.001 After 88.91 ± 14.03 Dyspnea severity* Before 5.6 ± 1.97 <0.0001 After 3.45 ± 1.94 Quality Of Life (total)# Before 35.5 ± 13.73 <0.0001 After 51.05± 20.30 General Health Before 50.95 ± 17.88 <0.0001 After 57.78 ± 17.09 Physical Status Before 1.37 ± 0.79 <0.0001 After 38.85 ± 23.09 Emotional Status Before 49.21 ± 23.61 <0.036 After 57.14 ± 24.63 Social Function Before 40.35 ± 21.88 <0.0001 After 51.42 ± 24.00 *: using Borg scale; #: using SF-36 questionnaire. SD: standard deviation. lack of awareness of patients and specialists regarding the role of outpatient’s rehabilitation, caused late referral of pa- tients to relevant centers for help and to reduce disease- related complications like dyspnea. Also, due to long-term and heavy hospitalization costs of medical treatment of pa- tients with severe COVID-19 in ICU and having physical and psychological fatigue related to the disease, and also being worried about re-infection or the spread of disease on the way to rehabilitation clinic, time-consuming PR exercises were not welcomed by some patients and they insisted on having just one training session instead of two weeks PR. However, giving educational brochures related to treatment sessions and encouraging the patients to work out through helping them feel recovered after exercises were the strengths of our study. 5. Limitations It should be mentioned that our study had several limita- tions, which need to be considered when interpreting find- ings; firstly, the small sample size of COVID-19 patients that were rehabilitated and also the absence of follow-up after PR due to limited research time and the probability of losing samples; secondly, the lack of a control group of COVID-19 patients post-ICU who were not rehabilitated; and thirdly no causal role of rehabilitation can be assumed with certainty. 6. Conclusion Based on the findings of this study, it seems that two-week exercise-based pulmonary rehabilitation could be effective in increasing the O2 saturation, decreasing dyspnea and pulse rate, and improving the QOL of severe COVID-19 pa- tients after discharge from intensive care unit. 7. Declarations 7.1. Acknowledgments We gratefully acknowledge the contribution of patients who participated in this study, their family members, Dr. Kian- mehr Aalipour(Research Assistance in PM&R Research Cen- ter) and the COVID-19 intensive care unit at Shohada-e- Tajrish Hospital, affiliated to Shahid Beheshti University of Medical Sciences. 7.2. Authors’ contributions Leila Angooti carried out the process of data gathering. Leila Angooti wrote the manuscript with support from Man- soor Rayegani, and Rama Bozorgmehr. Mansoor Rayegani, Rama Bozorgmehr helped supervise the project. Mansoor Rayegani, Rama Bozorgmehr, Leila Angooti and Amir hossein Mahdi kaghazi performed the manuscript proofing. This open-access article distributed under the terms of the Creative Commons Attribution NonCommercial 3.0 License (CC BY-NC 3.0). Downloaded from: http://journals.sbmu.ac.ir/aaem 5 Archives of Academic Emergency Medicine. 2022; 10(1): e45 7.3. 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