Agreement between invasive and oscillometric arterial blood pressure measurements using the LifeWindow multiparameter monitor and two cuff sizes in anesthetized adult horses.

The research highlights the inconsistency between noninvasive blood pressure measurements, done using the LifeWindow monitor with two different cuff sizes, and invasive blood pressure measurements in anesthetized horses. The results found that a 40% cuff width agreed better with the invasive measurements, however, neither of the cuff sizes or monitor models met the recommended guidelines.

Objective of the Research

• The main objective of this study was to evaluate the agreement between noninvasive blood pressure (NIBP) readings using LifeWindow multiparameter monitors (LW9xVet and LW6000V) and invasive blood pressure (IBP) readings in anesthetized horses.
• The secondary aim was to assess the agreement of NIBP readings using a cuff width to mid-cannon bone circumference ratio of 25% and 40%. This aimed to uncover whether changing cuff size may improve the accuracy of NIBP readings.

Methodology

• The study was a prospective, randomized clinical trial that included a total of 43 adult horses that were undergoing general anesthesia in dorsal recumbency (lying on their back) for various procedures.
• The anesthetic protocols differed according to the preference of the individual clinician.
• IBP measurements were taken after cannulation of the facial artery and established a connection to a transducer aligned with one of two LifeWindow multiparameter monitors.
• NIBP was measured on each horse with two different cuff widths that represented 25% or 40% of the mid-cannon bone’s circumference.
• A Bland-Altman analysis, a statistical method used to compare two different measurements techniques, was used to assess the bias and limits of agreement (LOAs) between the NIBP and IBP measurements.

Results

• The results concluded that the 40% cuff width performed better on all fronts — systolic arterial pressure (SAP), mean arterial pressure (MAP), and diastolic arterial pressure (DAP)— than the 25% cuff width.
• Despite the better performance of the 40% cuff, all tested methods, including both cuff sizes and monitor models, failed to meet the standards set in the American College of Veterinary Internal Medicine Consensus Statement Guidelines.

Conclusions

• The study concluded that, while using the LifeWindow multiparameter monitor in anesthetized horses, the 40% cuff width provided better agreement with the IBP measurements.
• However, the research also highlighted that both cuff sizes and monitor models under examination failed to meet the necessary guidelines set by relevant authorities, indicating a need for improved methods or stricter adherence to guidelines.