Oxygen concentrations at the rear and front of the bag in bag valve mask devices during oxygenation of neonates

The Ambu device can provide 100% oxygen from its rear part even at low flow rates and 100% oxygen during active ventilation provided at least 10 L/min oxygen is used. The VBM is at a disadvantage when the oxygen source faces a hole; as the jet flowing in the bag causes a Venturi effect; which sucks air in from outside and dilutes the oxygen concentration provided. The ridge type does not have this problem. Ventilation at a rate of 30 min−1 produced a higher oxygen concentration. The operator should be aware of the limitations of the device used.