1. Department of Critical Care Medicine, Instituto Nacional de Cancerología, Mexico City, Mexico
2. Department of Critical Care Medicine, Hospital Especialidades Centro Médico Nacional La Raza, Mexican Institute of Social Security, Mexico City, Mexico
3. Department of Critical Care Medicine, UMAE Hospital de Traumatologia “Dr. Victor de la Fuente Narvaez”, Mexican Institute of Social Security, Mexico City, Mexico
4. Department of Critical Care Medicine, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Mexico City, Mexico
5. Department of Critical Care Medicine, Medica Sur Clinic & Foundation, Mexico City, Mexico