[Development of an intrauterine distension pressure for hysteroscopy in the horse].

The research focuses on the development of an intrauterine distension pressure method for hysteroscopy in horses to enhance equine fertility diagnostics and surgery while minimizing potential complications.

Objective of the Research

The study aims to establish safe and effective intrauterine pressure for hysteroscopy in horses. This is crucial for a clear visualisation of intrauterine structures and ensuring efficient surgical procedures. Excessively high pressure and reabsorption of distension media during hysteroscopy can lead to fatal complications, reinforcing the need for this research.

Research Methodology

• The research involved monitoring intrauterine pressure in 28 healthy horses in diestrus or anestrus phases during hysteroscopy. This was accomplished using a transcervically inserted catheter.
• The horses were restrained and sedated for the procedure using xylazine and levornethadon.
• The research identified three distinct pressure types: Parb (pressure necessary for complete visualisation), Pcerv (pressure which triggered transcervical efflux of distension medium), and Pmax (maximum achievable intrauterine pressure).

Results

• Complete visualisation of the intrauterine structures was achieved with an average pressure of 17.8 mm Hg, with a variable range of 12.8 to 28.6 mm Hg.
• Higher intrauterine pressure of 62.5 +/- 10.0 mm Hg, significantly triggered the spontaneous efflux of distension media.
• The maximum pressure that could be reached, Pmax, was notably higher than both Parb and Pcerv, clocking in an average of 101.6 +/- 24.4 mm Hg.
• Clinical signs of discomfort or effects on the circulatory system were only registered when Pmax pressure was applied.

Conclusion

Based on the above findings, the study concluded that a safe and effective hysteroscopy can be performed with a mean pressure of 17.8 mm Hg and an upper limit of approximately 30 mm Hg. This research provides valuable inputs for performing equine hysteroscopy without eliciting discomfort or harmful side-effects on circulatory health.