Evaluation of the agreement between lingual and thoracic limb noninvasive blood pressure with invasive blood pressure measurements in anaesthetized horses.

The research explored how accurate noninvasive blood pressure measurements from the tongue and thoracic limb in anaesthetized horses are compared to invasive blood pressure readings. The findings showed that noninvasive readings, particularly from the tongue, were reasonably accurate and could be a viable alternative for assessing arterial blood pressure in sedated horses.

Research Methodology

• The study was a prospective clinical examination involving eight healthy horses. These horses were sedated for routine medical procedures. Their average weight was 498 ± 91 kg and their average age was roughly eight years.
• The horses received premedication with romifidine and methadone intravenously, and general anesthesia was induced with ketamine and midazolam. Isoflurane was then used to maintain the anesthesia.
• To get the invasive blood pressure (IBP) readings, the researchers inserted a catheter into the horse’s facial artery.
• Three different arterial pressures – systolic (SAP), mean (MAP), and diastolic (DAP) – were recorded every 20 minutes from noninvasive measurements (NIBP) from the tongue and thoracic limb, comparing with the IBP readings.

Interpreting the Results

• The agreement between invasive and noninvasive blood pressure readings was assessed based on two established criteria: the American College of Veterinary Internal Medicine, and the American Association for Medical Instrumentation. The Bland-Altman method was applied for this analysis.
• The accuracy of noninvasive readings in comparison with invasive standards proved satisfactory in most instances. NIBP measurements from the tongue had the lowest deviation from the IBP measurements, coming in within the accepted ranges.
• When blood pressure was lower than normal (hypotension), noninvasive mean and diastolic readings tended to overestimate the invasive readings. However, both accuracy and precision still met the criteria.

Conclusions

• Overall, noninvasive blood pressure measurements, particularly those from the tongue, were found to have fair accuracy and precision when compared to invasive measurements.
• The researchers concluded that the tongue is a suitable alternative to the thoracic limb for noninvasive blood pressure assessments.
• This method could prove an acceptable way of reliably detecting hypotension in healthy, sedated horses.