Effect of High Frequency Oscillatory Highflow Nasal Cannula on Desaturations and Bradycardia in Preterm Infants

Paired difference in respiratory rate

Time frame: 180-minute recording periods for each therapy

Paired difference in heart rate

Time frame: 180-minute recording periods for each therapy

Paired difference in fraction of inspired oxygen [FiO2]

Time frame: 180-minute recording periods for each therapy

Paired difference in peripheral oxygen saturation [SpO2]

Time frame: 180-minute recording periods for each therapy

Paired difference in the proportion of time spent with oxygen saturations < 80%

Time frame: 180-minute recording periods for each therapy

Paired difference in the proportion of time spent with heart rates < 80 bpm

Time frame: 180-minute recording periods for each therapy

Paired difference in the number of apneas requiring stimulation

Time frame: 180-minute recording periods for each therapy

Paired difference in transcutaneous CO2 measurements

Time frame: 180-minute recording periods for each therapy

Paired difference in pain assessment using 'Bernese pain scale'

Bernese Pain-Scale for Neonates (BPSN): a 9-item multidimensional pain assessment tool that includes behavioral and physiological indicators. The instrument consists of seven subjective (alertness, crying, consolation, skin color, facial expression, posture, and changes in respiratory rate) and two physiological (i.e. objective) (changes in heart rate and oxygen saturation) indicators. Each item is rated on a four point Likert scale (0, 1, 2, and 3). Higher scores indicate greater pain-related distress, and a total score of 11 or higher is considered to indicate pain.

Time frame: 180-minute recording periods for each therapy

Paired difference in end-expiratory lung impedance (EELI) in a subset of patients.

EELI using electrical impedance tomography (arbitrary units per kilogram).

Time frame: At the end of each intervention period

Paired difference in regional ventilation distribution in a subset of patients.

Regional ventilation distribution using electrical impedance tomography (arbitrary units per kilogram).

Time frame: At the end of each intervention period

Paired difference in Tidal volumes in a subset of patients.

Tidal volumes using electrical impedance tomography (arbitrary units per kilogram).

Time frame: At the end of each intervention period

Paired difference in nasal trauma score

Royal Women's Hospital Nasal Integrity and Pressure Chart. Nasal injury is defined as stage 0-skin intact; stage 1-nonblanchable erythema of intact skin; stage 2-partial thickness skin loss involving epidermis, dermis, or both; stage 3-full thickness skin loss involving damage to or necrosis of subcutaneous tissue; stage 4-full thickness skin loss with extensive destruction, tissue necrosis, or damage to supporting structures. Lowest Score: 0. Highest Score: 4. A higher score indicates more extensive nasal injury.

Time frame: At the end of each intervention period

Paired difference in the rate of pneumothorax

Time frame: 180-minute recording periods for each therapy

Paired difference in reaching 'failure criteria' to stop Osciflow or HF therapy:

Definition of failure criteria * Respiratory rate \>90/min for more than 30 minutes * Respiratory rate \>20/min higher than at the beginning of the study * Increase in FiO2 by ≥ 0.25 from baseline for more than 30 minutes * Apnea-Score of more than 20/4 hours

Time frame: 180-minute recording periods for each therapy