Respiratory Function 3 Months After Hospital Discharge in Critically Ill COVID-19 Patients

Study Overview
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Brief Summary
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The objective of this single-center retrospective observational study is to describe spirometric abnormalities and their impact on 6-minute walk test (6MWT) and the physical component summary (PCS) of the SF-36 quality of life instrument.at least 3 months later discharge hospital.

Detailed Description
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Background: The COVID-19 pandemic has already affected more than 400 million people worldwide and resulted in at least 6 million deaths. The disease has also resulted in a growing population of individuals, with both physical and mental sequelae. Pulmonary sequelae have been the subject of several studies because the lung is the main target organ of the disease. However, there is still unknown data about the pulmonary manifestations and their spirometric patterns after a critical illness and also its consequences in quality of life. Purpose: Up to 20% of COVID-19 patients develop severe forms of the disease and require ICU admission. Most of these patients at hospital discharge still have several limitations that impact on quality of life. Some studies have analyzed pulmonary functional alterations after a variable period of time and have found results that vary from the absence of functional alterations to restrictive and diffusion impairment. Few studies have analyzed changes in small airways, and those that have evaluated have found no changes. The objective of this single-center retrospective observational study is to describe spirometric abnormalities and their impact on 6-minute walk test (6MWT) and the physical component summary (PCS) of the SF-36 quality of life instrument.at least 3 months later discharge hospital. Primary outcome: To describe spirometric patterns associated to severe COVID-19 survivors at least 3 months after hospital discharge. Secondary outcomes: Correlate the results of the spirometric evaluation with the 6-minute walk test (6MWT) and the physical component summary (PCS) of the SF-36 quality of life instrument. Methods: An observational retrospective study will be conducted, including all 18 years and older patients with severe COVID-19, confirmed by real-time reverse transcriptase-polymerase chain reaction., admitted to a 35- bed intensive care unit of a tertiary hospital from April 2020 to October 2021. Pediatric, pregnant or breastfeeding women and palliative care patients as well as chronic obstructive pulmonary disease and symptomatic asthmatic patients will be excluded. Population is estimated at 60 patients. Data collecting will be finished in February 2022. Patients routinely are assessed after at least 3 months after hospital discharge in our multidisciplinary follow-up clinic. A trained research team will routinely apply the 6 minute walk test (6MWT), a Pulmonary Function Test (PFT) and Short Form Health Survey 36 (SF-36) physical component summary (PCS) of SF-36

Official Title
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Respiratory Function 3 Months After Hospital Discharge in Critically Ill COVID-19 Patients

Conditions
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COVID-19

Intervention / Treatment
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* Diagnostic Test: Spirometric evaluation
* Diagnostic Test: Physical component summary
* Diagnostic Test: 6MWT


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria All 18 years and older patients with severe COVID-19, confirmed by real-time reverse transcriptase-polymerase chain reaction., admitted to a 15- bed intensive care unit of a tertiary hospital from April 2020 to October 2021. Exclusion criteria < 18 years old Pregnant Breastfeeding Chronic pulmonary obstructive disease Symptomatic asthma

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Respiratory function 3 months after hospital discharge in critically ill COVID-19 patients<br>All critically ill adult patients admitted to the ICU with confirmed diagnosis of COVID-19 were submitted at least 3 months after hospital discharge to spirometry (FVC, FEV1, FEV1 /;FVC and FEF 25-75%), the 6-minute walk test (6MWT) and evaluation of the physical component summary (PCS) of the SF-36 quality of life instrument. | Diagnostic Test: Spirometric evaluation<br>* Evaluation of: forced vital capacity (FVC),, FEV1', FEV 1/FVC, FEF 25-75<br>Diagnostic Test: Physical component summary<br>* Evaluation of the physical component summary of SF-36 quality of life<br>Diagnostic Test: 6MWT<br>* 6 minute walk test<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Forced vital capacity (FVC) | Forced vital capacity (FVC) is the volume of air that can forcibly be blown out after full inspiration, Measured in liters. Normal value > 80% of predicted for age, sex, heigth and ethnicity | 3 months after hospital discharge | 
| Forced expiratory volume in 1 second (FEV1) | FEV1 is the volume of air that can forcibly be blown out in first 1 second, after full inspiration. Measured in liters. Normal value > 80%. of predicted for age, heigth and ethnicity. | 3 months after hospital discharge | 
| FEV1 / FVC Ratio | Represents the proportion of vital capacity that the patients are able to expire in the first second of forced expiration (FEV1) to the full, forced vital capacity (FVC). The result of this ratio is expressed as FEV1%. Normal values are > 75%.of predicted that depend on age, sex, height, and ethnicity | 3 months after hospital discharge | 
| Forced mid-expiratory flow (FEF25-75%) | Defined as the mean forced expiratory flow during the middle half of the FVC . Normal value > 65% of predictedf for age, sex, heigth and ethnicity | 3 months after hospital discharge | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Physical Component Summary (PCS) of Short Form- 36 (SF-36) Instrument | PCS is composed of four scales assessing physical function, role limitations caused by physical problems, bodly pain and general health. The result scale ranges from 0 to 100, with 0 being the worst result and 100 the best. | 3 months after hospital discharge | 
| 6 Minute Walk Test | The patient is placed on a flat, rigid area 30 meters long and instructed to walk the longest tolerable distance for 6 minutes. Measured in meters. The result is given as a percentage of the normal predicted value for age, sex, height and weight calculated by the Enright and Sherril equation. | 3 months after hospital discharge | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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COVID-19, Critical Care, Survivors, Pulmonary function test, Physical component summary