High-flow nasal cannula therapy is a broadly used instrument of respiratory support in pediatric and adult patients with respiratory failure.~For adult patients with pneumonia and respiratory failure, there is a validated index (ROX; ratio SpO2/FiO2) which helps to identify those at risks for the need of intubation.~This index however is not applicable in the pediatric population because the physiological values of respiratory rate vary greatly across different ages.~Thus, based on the particularities of pediatric patients the investigators developed an index that integrates different flow-settings in HFNC therapy with non-invasively measured clinical parameters of oxygenation. The BPOI is defined as the ratio of the product of the peripherally measured oxygen saturation and the patient's body weight divided by the product of HFNC flow and the fraction of inspired oxygen:~BPOI = (SpO2 * kg) / (Flow * FiO2)
The investigators developed an index that integrates different flow-settings in High-flow nasal cannula (HFNC) therapy with non-invasively measured clinical parameters of oxygenation in pediatric patients. This observational study is designed to evaluate this index and to determine a cut-off value for imminent HFNC failure.