Many innovators around the world are busy working on affordable ventilators that can be mass produced. It does make one wonder as to why are these systems so expensive and difficult to make, given the advances in tech. tools and software over the last decade. Think of the following possibilities.
1. The ventilator has to be in-step with the breathing pattern of the patient, which keeps changing in time. Which requires continuous monitoring and fast adjustments.
2. The ventilator capacity should be adjustable to the lung capacity of the patient.
3. The on board arduino clock may require regular resetting which has to be done as unobtrusively as possible.
4. The optimun pressure range has to be maintained. More pressure may damage the lungs. Less pressure may cause difficulty in breathing.
5. Sufficient back-up mechanism should be there in case of a sensor failure.
6. Design should manage to avoid system hang-up.
These and similar other concerns require a careful design and testing and quality control before the devices can be used in field.