Effects of CPAP in Severe Therapy-resistant Asthma
Condition: Asthma
MeSH terms: Asthma
Study type: Interventional

Summary: 
      The purpose of this study is to verify the effects of continuous positive airway pressure
      (CPAP) on exercise capacity of children and adolescents with severe therapy-resistant asthma
      (STRA). A randomized, controlled, crossover clinical trial will be conducted. We expect the
      use of CPAP to increase exercise capacity in children and adolescents with STRA.
    

Detailed description: 
      This project aims to verify the effects of continuous positive airway pressure (CPAP) on
      exercise capacity of children and adolescents with severe asthma therapy-resistant (STRA). A
      randomized, controlled, crossover clinical trial will be conducted. Children and adolescents
      between 6 and 18 years old, with a diagnosis of STRA, will be included in the study. Patients
      wil be recruited in the São Lucas Hospital (HSL) Asthma Outpatient Clinic of the Pontifical
      Catholic University of Rio Grande do Sul. Patients who accept to participate in the study
      will perform a medical consultation according to routine outpatient asthma clinic,
      anthropometric evaluation and pulmonary function tests. Afterwards, they will be randomized
      into control and intervention groups. Participants in the intervention group will use
      noninvasive ventilation (NIV) in CPAP mode with 10cmH2O of positive end-expiratory pressure
      (PEEP), fraction of inspired oxygen (FiO2) of 0.21, for a period of 40 minutes. Participants
      in the control group will use NIV (CPAP), with a minimum PEEP of 1cmH20 and a FiO2 of 0.21
      also for 40 minutes. Afterwards, patients from both groups will perform a maximum
      cardiopulmonary exercise test (CPET). A sample size of 18 individuals to be included in the
      study was estimated. The variables studied will be maximal oxygen consumption and the
      anaerobic threshold (that measures exercise capacity), distance and time (to measure exercise
      tolerance), peripheral oxygen saturation, peak expiratory flow and the sensation of dyspnea
      at the end of the CPET.
    

Intervention name(s): Continuous Positive Airway Pressure (CPAP)
Intervention type(s): Device
Intervention description(s): In the first moment, CPAP will be installed, and the researcher will hold a mask in the position in which it is coherent, explaining the method to the patient and allowing their gradual adaptation. Patients will adapt for a few minutes to make sure the mask is consistent with the specifications, so that the patient is comfortable. Participants in the intervention group will start with a PEEP of 1cmH2O that will increase by 2 cmH2O until a PEEP of 10 cmH2O is reached. Therefore, participants in the intervention group will remain with CPAP, PEEP of 10cmH2O, FiO2 0.21, for a period of 40 minutes.
Allocation: Randomized
Intervention model: Crossover Assignment
Intervention model description: Patients will be randomized, through a sealed envelope, to initially compose the intervention group or the control group. The sequential order of randomization will be kept confidential with a single investigator, so that the other professionals involved and responsible for data collection will be blinded throughout the study period. Individuals who initially composed the intervention group will then perform, in a second moment, the procedures of the control group.
Masking: Double (Investigator, Outcomes Assessor)
Primary purpose: Treatment
Keywords: Asthma; Continuous positive airway pressure; Oxygen consumption