Agreement of Bioreactance Cardiac Output Monitoring With Thermodilution in Healthy Standing Horses.
Authors: Hopster Klaus, Hurcombe Samuel D A
Journal: Frontiers in veterinary science
Summary
# Editorial Summary: Bioreactance Cardiac Output Monitoring in Horses Accurate, non-invasive measurement of cardiac output remains challenging in equine practice, yet haemodynamic assessment is critical for managing critically ill horses and those under general anaesthesia. Hopster and Hurcombe evaluated bioreactance-based non-invasive cardiac output monitoring (NICOM) against the thermodilution gold standard in six healthy standing horses, deliberately inducing low, normal, and high cardiac output states using xylazine sedation and dobutamine infusion. The bioreactance method demonstrated strong correlation with thermodilution measurements across all cardiac output ranges (89% concordance on 4-quadrant analysis), though the Bland–Altman analysis revealed a mean bias of −0.26 L/min with limits of agreement spanning −3.88 to 3.41 L/min—a clinically acceptable margin for a non-invasive technique. Whilst these findings are encouraging for potential clinical adoption, the authors appropriately emphasise that validation under true intensive care and anaesthetic conditions remains necessary before practitioners can confidently use NICOM to guide therapeutic decisions in compromised horses. The technique's ability to provide continuous, non-invasive haemodynamic monitoring without arterial catheterisation positions it as a valuable tool for equine critical care once clinical utility is formally established.
Read the full abstract on PubMed
Practical Takeaways
- •NICOM bioreactance offers a non-invasive alternative to thermodilution for monitoring cardiac output in standing horses across various hemodynamic states
- •Clinicians should be aware of the systematic underestimation bias (~26% lower) when interpreting NICOM values and comparing to expected thermodilution values
- •This technology shows promise for ICU and anesthetic monitoring in equine practice, but validation under true clinical conditions (disease, anesthesia) is needed before routine clinical application
Key Findings
- •Bioreactance (NICOM) and thermodilution showed high correlation for cardiac output measurement across low, normal, and high output states with 89% concordance rate
- •Linear regression revealed NICOM underestimated cardiac output compared to thermodilution (Y = 0.4874·X + 0.5936)
- •Bland-Altman analysis demonstrated mean bias of -0.26 L/min with limits of agreement ranging from -3.88 to 3.41 L/min