We planned to use the following as secondary outcomes:
1. average tidal volume (TV), or volume of air inspired and
expired in each normally ventilated cycle;
2. forced expiratory volume in one second (FEV1), the
expiratory volume obtained during the first second of execution
of the forced vital capacity;
3. vital capacity (VC), the largest amount of air that a person
can expel from the lungs shortly after having filled them to the
maximum capacity;
4. functional residual capacity (FRC), the amount of air that
stays in the lungs at the end of normal expiration;
5. forced vital capacity (FVC), the total amount of air expired
during a forced expiration after a maximum inspiration;
6. length of stay in hospital;
7. evidence of harms from IS;
8. all-cause mortality;
9. cost analysis.
We planned to perform subgroup analyses to estimate the efficacy
of the different types of devices:
1. Triflo;
2. Voldyne;
3. Spirocare;
4. Coach;
5. Bartlett-Edwards incentive spirometer.