Airway Flow of RAM Cannula With BCPAP in Infants

The RAM Cannula interface is used as routine interface for newborn infants receiving CPAP treatment for respiratory distress. Compared to the standard systems that have been used for more than 50 years, the interface has high resistance and has not been extensively studied. The delivered quality of the CPAP support is likely to be negatively affected by the interface resistance. We hypothesise that exhalations through the device is uncommon and that the interface resistance restricts flow from the patient. If expiratory flows are uncommon the RAM interface provide support clinically comparable to other systems based on unidirectional flow such as humidified high-flow cannula. This is a cross-sectional, observational study (no intervention) in newborn infants that are clinically stable and on respiratory support with the RAM interface connected to a bCPAP circuit. This is the most common support in the Phu San neonatal unit. The time needed for data collection is short and collection is expected to take approximately five minutes (less than 15 minutes) in a quiet infant. The collection can be planned to minimize disturbances for the infant, parents and staff. For example, the busiest times of the day can be avoided to not intervene with daily care, ward rounds or examinations of the infant. Data on flow and pressure will be collected within the respiratory support circuit at the connection to the RAM interface. The measurements are passive, and no tests or manipulation of the infant is planned. There will be brief interruptions (\<1 min) in respiratory support when the meters are connected. Similar interruptions are very common and occurs several times per day during normal care. Data will be collected in case report forms (CRF) with REDCap electronic data capture tool. All personal identifiers will be removed before data export from REDCap and further analysis only using enrolment numbers. Background variables describing the pregnancy, delivery and the infant w