The Performance of Blow-by Method Using Pediatric Non-Rebreathing Mask for Oxygen Delivery During Transport of Pediatric Patients: A Laboratory Study.

Purpose: The blow-by method using a pediatric non-rebreathing mask (PNRM) is commonly employed to maintain oxygenation during transport of pediatric patients after general anesthesia. This study aimed to evaluate the performance of the blow-by method using a PNRM with an oxygen flow rate of 10 liters per minute (LPM) during simulated transport of pediatric patients. Patients and Methods: This laboratory study was simulated along a 32-meter corridor from the pediatric operating room to the post-anesthesia care unit at Srinagarind Hospital. A pediatric mannequin was positioned laterally on a transport trolley. A PNRM delivering oxygen at 10 LPM was placed at distances of 0, 5, and 10 cm from the mannequin's nose. The fraction of inspired oxygen (FiO2) at the mannequin's nose was measured every 2 meters along the corridor. Each distance condition was tested 10 times. The primary outcome was whether the blow-by method could maintain FiO2 above 40% at all measurement points during simulated patient transport. Results: Oxygen delivery was adequate only when the PNRM was placed at 0 cm from the nose, with a mean FiO2 of 86.9 ± 0.3%, In contrast the mean FiO2 values at 5 and 10 cm was 28.5 ± 0.3%, and 24.1 ± 0.1%, respectively. The mean FiO2 difference between 0 and 5 cm was 58.4% (95% CI: 56.8-60.1; p < 0.001), and between 0 and 10 cm was 62.8% (95% CI: 61.5-64.1; p < 0.001). Conclusion: The blow-by method using PNRM positioned at 0 cm from pediatric mannequin's nose provided adequate oxygenation throughout transport. Clinically, therefore, maintaining a close PNRM position is essential.