1. Faculty of Medical Sciences, University of Guayaquil, Guayaquil, Ecuador
2. Physiology and Respiratory-Center Briones-Claudett, Guayaquil, Ecuador
3. Faculty of Medical Sciences, Espiritu Santo University, Samborondón, Ecuador
4. Intensive Care Unit, OMNI Hospital, Guayaquil, Ecuador
5. School of Medicine, San Francisco de Quito University, Quito, Ecuador