The Pnoi-phone is a novel device for evaluating variables in the Pulmonary Function Test (PFT) for the diagnosis and monitoring of asthma. The device uses microphones to capture breath sounds from the mouth and chest simultaneously. Then it uses data-driven algorithms to calculate PFT variables, which are used to diagnose and monitor asthma.

Currently, spirometry is the gold standard test for lung health. It works by measuring how much volume of air one can inhale and exhale and how quickly one can do it. It is a reliable test, but it requires well-trained personnel to execute, and it is time consuming, expensive, and unavailable in remote settings where medical facilities are limited. The Pnoi-phone is a more affordable, portable and easy-to-use alternative that could be used to diagnose respiratory diseases even in remote clinics.

Currently, physicians are using digital stethoscopes to enhance and store auscultation sounds recorded on the chest. The Pnoi-phone is an extension to a digital stethoscope that enables it to record breath sounds from the mouth and chest simultaneously. It is wirelessly controlled by a smartphone (Pnoi-phone app), and stores the recorded data. A data-driven algorithm processes the recorded data and predicts the PFT variables which are displayed in the Pnoi-phone app.

A prototype is built that can record breath sounds from the chest and mouth simultaneously. The recording is carried out at four locations of the chest (two anterior and two posterior). For five breath cycles at each location, it takes approximately 5-6 minutes for the complete recording. The product is under further development for recording quality and optimal product design.

Based on the expenses of the prototype, the product can be made available at USD $250, which is considerably lower than the spirometer which costs USD $ 1000 - $ 2500. This will significantly reduce the cost per test. Therefore, it has the potential to reach a large population. It can also serve for educational and research purposes.

Here are some features of the Pnoi-phone:

• It is powered by a rechargeable battery and power saving mode.
• Easy to use and requires minimal training for healthcare workers
• It can be connected to a computer or mobile device for data transfer and analysis.
• Works as a normal stethoscope in power-off mode

Acoustic epidemiology is a field of study that analyses bodily generated sounds for the distribution of diseases. The Pnoi phone is a promising new technology that has the potential to have a significant impact in this field.