Operation of the Babybird ventilator at high circuit flows and ventilator rates causes resistance to exhalation in the expiratory limb of the breathing circuit. Use of the expiratory flow gradient feature may not adequately reduce this resistance, which often results in undesirable levels of CPAP or expiratory retard. To eliminate these problems, we modified the expiratory portion of the Babybird ventilator circuit, enlarging the PEEP-flow orifice to 12 mm and adding a second exhalation valve, parallel to the existing one. These simple modifications make the Babybird suitable for a wider range of clinical applications.
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