A portable fan-based device for evaluating lung function in horses by the forced oscillation technique.

The research focused on developing a portable, non-invasive device to evaluate lung mechanics in horses using the forced oscillation technique (FOT). The device, which uses a servomechanism to generate pressure waveforms, proved successful in testing and provided significant value for the field of veterinary respiratory medicine.

Background

• The examination of lung mechanics in horses has traditionally depended upon invasive procedures, often necessitating sedation.
• While the forced oscillation technique (FOT) offers a non-invasive alternative, most FOT devices are complex, bulky, and expensive, making them challenging to use for horses.

Aim of the Study

• To develop a portable and less convoluted FOT device that facilitates non-invasive assessment of respiratory mechanics during spontaneous breathing in horses.

Research Approach and Method

• The researchers engineered a portable FOT device that generates pressure waveforms utilizing a servo-controlled ducted fan, an innovative approach that enables the creation of more durable, compact, and mobile equipment.
• The prototype consists of a small microcontroller-based electronic board to control the fan and measure flow and pressure, and an optimized data processing algorithm.
• The study included the measurement of the device’s performance, with results indicating a maximum error of 0.06 cmHO·s/L and 0.15 cmHO·s/L in gauging respiratory resistance and reactance, respectively, during validation.
• A pilot study was also executed on three healthy and three severe equine asthma (SEA) horses to determine the device’s tolerability and feasibility.

Outcomes

• The results showed a significant difference between the two groups in terms of total respiratory system resistance (Rrs) and reactance (Xrs).
• Rrs at 5 Hz was 0.66 ± 0.02 cmHO·s/L in healthy horses versus 0.94 ± 0.07 cmHO·s/L in SEA horses. Xrs was 0.38 ± 0.02 cmHO·s/L in healthy horses and -0.27 ± 0.05 cmHO·s/L in SEA horses.

Conclusion

• This innovative approach allowed the construction of a small, cost-effective, and portable device for performing non-invasive assessment of respiratory mechanics in spontaneously breathing horses.
• The study presents this device as a substantially beneficial tool for progressing veterinary respiratory medicine.
• The results also suggest the potential of applying this innovative approach in developing portable FOT devices for human applications.