Tafonius does not use any pressurized gas to drive the ventilator. Instead, a precision motor system controls piston movement. This results in silent operation, reduced running costs, and precise control. The advanced motor system and motor control means that the piston can behave like a virtual bag during spontaneous ventilation and during the expiratory phase of controlled ventilation. Also, any part of the respiratory cycle can be executed as a series of phases of varying lengths. Any phase can have a resolution of less than 1/100th second. During normal IPPV, for example, only one phase is used during inspiration and it lasts the full length of inspiration. During expiration, multiple phases are used each one lasting 5ms (200 times per second). In each of these phases, airway pressure is measured and the piston moved accordingly. Not only does this system provide very smooth control of breathing but allows the implementation of an Airway Servo System to control patient airway pressure.
If the Servo Airway pressure is set to 0 cm H2O then the patient experiences no resistance to breathing out, significantly reducing the work of breathing. To the patient it feels like exhaling to ambient with no machine attached. If the Servo Airway pressure is set to 5cm H2O then the patient experiences 5cm of CPAP or PEEP. With the combination of multiple phases and an Airway Servo System, any pattern of breathing can be designed and implemented. In time, researchers will develop a library of ventilating modes, patterns, sequences and maneuvers that can be used to ventilate your patient. You will no longer need to buy another machine to obtain new features.
"Tafonius - undeniably the last word in mechanical lung ventilators"
The University of Edinburgh Royal (Dick) School of Veterinary Studies