A study of measurement of noninvasive blood pressure with the oscillometric device, Sentinel, in isoflurane-anaesthetized horses.

This research study evaluated the accuracy of a noninvasive blood pressure monitoring device called the Sentinel in anaesthetized horses compared to standard invasive methods. The study found that the Sentinel was less accurate and more variable in its readings, and often failed to deliver results, concluding it is not an appropriate alternative for invasive blood pressure monitoring in anaesthetized horses.

Research Methodology

• The study utilized both invasive and noninvasive methods of measuring blood pressure in anaesthetized horses.
• A total of 29 horses were part of the study, and blood pressure was measured using various techniques.
• Invasive blood pressure was gauged via a catheter in the facial artery, transverse facial artery, or metatarsal artery.
• Noninvasive blood pressure was estimated using the Sentinel device with appropriately sized cuffs placed on a metacarpal or metatarsal bone or the tail, in random order.
• Both methods were used to record systolic, mean, and diastolic arterial blood pressures, as well as heart rates.
• The study sought to assess if the differences between noninvasive and invasive measurements were influenced by the animal’s weight, position during measurement, location of the cuffs, or use of acepromazine as a premedication.

Results of the Study

• The study found that the noninvasive method of blood pressure measurement generally yielded higher results than the invasive method.
• However, the Sentinel device’s readings were not consistently accurate, and often varied depending on the position of the horse and cuff placement.
• The data indicated that the noninvasive method was approximately two times more variable than the invasive method in capturing blood pressure readings.
• There were no significant differences in either method related to the horse’s weight or the use of acepromazine premedication.
• Notably, 21.7% of the time, the Sentinel device failed to deliver a reading.

Conclusion

• As per the study’s findings, noninvasive blood pressure measurements taken by the Sentinel device, as described in the study, are not considered a suitable substitute for invasive methods when monitoring blood pressure in anesthetized horses.
• Despite the advantages of a noninvasive approach, inconsistent readings and frequent failure to deliver a reading indicate that the Sentinel may not provide reliable or accurate blood pressure monitoring in this context.