Agreement between invasive blood pressures measured in three peripheral arteries in anaesthetized horses under clinical conditions.

The research article focuses on evaluating the congruence between blood pressure measurements taken from different peripheral arteries on anaesthetized horses during surgery. The study found that blood pressure readings from different peripheral arteries cannot be interchangeably used due to poor and random agreement of the results.

Methodology

• The study employed a prospective balanced incomplete block design on a sample of 18 client-owned horses undergoing elective surgery.
• The invasive blood pressure (IBP) was concurrently measured in separate combinations of three peripheral arteries: the transverse facial and facial artery, the transverse facial and metatarsal artery, and the facial and metatarsal artery. Each combination was tested on six horses.
• For each sampling, systolic (SAP), mean (MAP), and diastolic (DAP) arterial pressures were measured, and the average of three consecutive measurements was recorded. The horse’s position, heart rate, and usage of a drug called dobutamine were also logged.

Results

• A total of 54 paired measurements were conducted, generating 18 paired measurements for each arterial combination.
• All paired measurements showed poor and haphazard (nonsystematic) agreement, indicating a significant disparity in readings between different peripheral sites.
• The widest limit of agreement was seen in systolic pressures measured between the facial and metatarsal artery, with a bias of -11 mmHg and a limit of agreement of 51 mmHg.
• Contrastingly, the smallest limit of agreement was 16 mmHg for the mean arterial pressures measured between the transverse facial and metatarsal artery, with a slight bias of 1 mmHg.

Conclusions

• The study concluded that there is a poor and haphazard agreement between blood pressures measured in different peripheral arteries.
• The implication of this finding is significant, especially for those studies where IBP is employed as an outcome variable. It’s also relevant when determining the agreement between noninvasive blood pressure and IBP measurements in horses under general anesthesia, as the location of the readings can substantially influence blood pressure values.