Assessment of Portable Oxygen Concentrators in Infants Undergoing Hypoxic Challenge Testing.

Assessment of Portable Oxygen Concentrators in Infants Undergoing Hypoxic Challenge Testing. A Randomized Crossover Study.

Hypoxic Challenge Testing (HCT) is the recommended method for inflight hypoxia risk assessment. Onboard oxygen administration remains controversial. The Federal Aviation Administration approved portable oxygen concentrators (POCs) for onboard oxygen supply but there is lack of evidence about the use, especially in children. The aim of our study is to establish the effectiveness and safety of POCs in infants undergoing HCT.

According to a forecast by International Air Transport Association the number of people travelling on commercial aircrafts is predicted to rise up to 8.2 billion passengers in 2037. Therefore evidence-based flight recommendations will gain importance in the future, especially for patients suffering from chronic diseases. Hypoxic Challenge Testing (HCT) is the recommended method for inflight hypoxia risk assessment where nitrogen is introduced in a plethysmograph reducing FiO2 (fraction of inspired oxygen) to 0.15. Oxygen supply is recommended if PaO2 (partial pressure of oxygen in arterial blood) drops <50-55 mmHg (in adults) or Sat.O2 (oxygen saturation) ≤ 85% (in infants) where non-invasive pulse oximetry is the recommended method for hypoxia assessment. Onboard oxygen administration remains controversial. The effectiveness of pulsed-dosed systems remains unclear in small patients due to shallow breathing patterns. The aim of our study is to establish the effectiveness and safety of POCs in infants undergoing HCT.

Infants, Hypoxia Altitude Simulation Test, Oxygen Delivery Device, Portable Oxygen Concentrator, Hypoxic Challenge Testing

Randomized crossover study (according to a random number table): Patients are allocated randomly to two study groups (cPOC/pPOC). In case of Sat.O2 drop ≤ 85% during HCT, oxygen is administered by cPOC (continuous-flow). For patients who show a positive POC hypoxic reversal, HCT is repeated at 24 hours and oxygen is administered by pPOC (pulsed-flow).

Randomized crossover study (according to a random number table): Patients are allocated randomly to two study groups (cPOC/pPOC). In case of Sat.O2 drop ≤ 85% during HCT, oxygen is administered by pPOC (pulsed-flow). For patients who show a positive POC hypoxic reversal, HCT is repeated at 24 hours and oxygen is administered by cPOC (continuous-flow).

InogenOne G3® (Inogen,Goleta,CA) on pulsed-flow mode: setting 2 (flow rate 420 ml/min, 16.8 ml +/- 3ml per bolus at 25 rpm).

Assessment of portable oxygen concentrators (POCs) to change HCT induced hypoxia (Sat.O2 drop ≤ 85%).

Hypoxia (Sat.O2 drop ≤ 85%) measured by Masimo SET Radical-7 Electron® pulse oximeter is induced performing HCT. Thereafter oxygen is administered through cPOC or pPOC until baseline Sat.O2 (Sat.O2 >93%) is achieved.

Compare the capacity of different POCs: continuous flow (cPOC) versus pulsed flow (pPOC) to change HCT induced hypoxia (Sat.O2 ≤ 85%) until baseline Sat.O2 (Sat.O2 >93%) is achieved.

Relationship between patient age (months) and POCs capacity to change hypoxic state (≤ 85%) to baseline Sat.O2 (>93%) measured by Masimo SET Radical-7 Electron®

Relate patient weight (kilograms) to POCs capacity to change HCT induced hypoxia (Sat.O2 drop ≤ 85%).

Relationship between patient weight (kilograms) and POCs capacity to change hypoxic state (≤ 85%) to baseline Sat.O2 (>93%) measured by Masimo SET Radical-7 Electron®

Inclusion Criteria: Patients with baseline Sat.O2 >94% AND <1 year with neonatal respiratory disease required oxygen supply in the last 6 months chronic respiratory disease (eg cystic fibrosis, obstructive or restrictive pulmonary disease) with FEV 1 (forced expiratory volume in 1 second) or FVC (forced vital capacity) <50%. Exclusion Criteria: acute respiratory infection

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