Related Experiment Video
Updated: Jun 22, 2026

Conducting Respiratory Oscillometry in an Outpatient Setting
Published on: April 8, 2022
Dynamic respiratory endoscopy without treadmill in 68 performance Standardbred, Thoroughbred and saddle horses under
L-M Desmaizieres1, N Serraud, B Plainfosse
1La Clinique du Cheval, 3910 route de Launac, 31330 Grenade.
Reasons For Performing Study:
High speed treadmill endoscopy provides a true assessment and diagnosis of the dynamic obstructions of the upper equine respiratory tract (DO-URT). However, treadmills do not always allow reproduction of the exact conditions of dynamic collapse of the URT. The availability of on-board endoscopes, which could be used without a treadmill, would make exercising endoscopy readily available to more equine practices.
Objectives:
To develop and validate an innovative endoscope which could be used for the examination of the URT at exercise in ridden and harnessed sport horses performing in natural conditions.
Methods:
Authors worked closely with engineers of a company manufacturing veterinary endoscopes. Over a 2-year period several prototypes were tested on more than 20 cooperative horses performing either in trot, gallop, jumping or endurance. The final Dynamic Respiratory Scope (DRS) allows real-time visualisation of the URT and video recordings for post test reviewing and archiving. The DRS was then tested in 2 equine livery yards. Performance horses presented for investigation of abnormal respiratory noises at exercise and/or poor performance were subjected to exercising endoscopy. Endoscopic images of the URT were recorded and video recordings of the URT were reviewed post test.
Results:
A total of 68 horses were examined: 39 harnessed Standardbred and 29 mounted horses (16 Thoroughbred and 13 saddle horses). Of these, 44 were diagnosed with a URT abnormality. Good quality videos were obtained even at maximum speed in all cases. The innovative insertion tube provided very stable images compared to those obtained with flexible video endoscopes on treadmills.
Conclusions:
This study validates the safety and the reliability of the DRS for imaging the equine URT during natural exercising conditions.
Potential Relevance:
Most common causes of DO-URT can be diagnosed easily during any type of performance without a treadmill and the DRS offers a great potential for further URT clinical research.
Related Concept Videos
Assessment of Ventilation I: Respiratory Rate
A Ventilation assessment is critical for monitoring a patient's health status. Respiration, one of the most accessible vital signs, provides insights into the function of numerous body systems and can indicate serious health issues, such as brainstem injuries from head trauma.
Critical Guidelines for Assessing Ventilation:
Assessment of Ventilation II: Respiratory Depth and Rhythm
Respiratory depth measures the volume of air inhaled or exhaled during a breath. It can vary from shallow to deep and typically remains consistent when a person is at rest or asleep. Occasionally, individuals will automatically inhale deeply, known as sighing, which inflates the lungs with more air than normal breathing.
To assess respiratory depth, observe the degree of chest excursion or movement:

