Accuracy and precision of oscillometric blood pressure in standing conscious horses.

This study examined the accuracy and precision of a non-invasive blood pressure device for measuring arterial blood pressure levels in standing, conscious horses. The researchers found that the device provided accurate data for measuring mean arterial pressure but showed variability during subnormal blood pressure conditions.

Research Context

• The researchers were studying the accuracy and precision of measuring arterial blood pressure (BP) in horses—relevant clinical data which can be used to assess factors such as tissue perfusion and pain.
• This is particularly important as there are currently no validated oscillometric non-invasive blood pressure (NIBP) devices specifically designed for use in horses.

Methods

• The research involved seven healthy horses from a teaching and research herd.
• An arterial catheter was inserted into either the facial or transverse facial artery and connected to a pressure transducer, a device which converts pressure into an analog electrical signal.
• A cuff for NIBP was placed around the base of the tail of each horse.
• The researchers then recorded the BP during normal conditions, induced hypertension through dobutamine administration, and imposed subnormal BP via acepromazine administration.
• To analyze the data, an agreement analysis with replicate measures was employed to calculate the bias (accuracy) and standard deviation of bias (precision).

Results

• The study analyzed a total of 252 pairs of invasive arterial BP and NIBP measurements.
• In comparison to the direct BP measures, the NIBP device showed a mean arterial pressure (MAP) accuracy of -4 mm Hg and a precision of 10 mm Hg.
• The systolic arterial pressure (SAP) had an accuracy of -8 mm Hg and a precision of 17 mm Hg, while the diastolic arterial pressure (DAP) had an accuracy of -7 mm Hg and a precision of 14 mm Hg.

Conclusion

• The MAP measurements from the NIBP monitor were proven to be accurate and precise across a range of BP conditions in adult horses.
• However, variability was detected during subnormal BP conditions.
• Based on these findings, the researchers concluded that MAP, but not SAP or DAP, can be reliably used for making clinical decisions in conscious horses.