Accuracy and Precision of Noninvasive Blood Pressure in Normo‐, Hyper‐, and Hypotensive Standing and Anesthetized Adult Horses

Abstract

BackgroundBlood pressure is relevant to the diagnosis and management of many medical, cardiovascular and critical diseases. The accuracy of many commonly used noninvasive blood pressure (NIBP) monitors and the accuracy of NIBP measurements in hypo‐ and hypertensive standing horses has not been determined.Hypothesis/ObjectivesThe objective of this study was to investigate the accuracy of an oscillometric BP monitor in standing horses before and during pharmacologically induced hyper‐ and hypotension and to compare results in standing and anesthetized horses.AnimalsEight standing mares from a research herd (SG) and eight anesthetized horses from a hospital population (AG).MethodsProspective experimental and observational studies. Invasive blood pressure (IBP) and NIBP, corrected to heart level, were measured simultaneously. In the SG hyper‐ and hypotension were induced by administration of phenylephrine (3 μg/kg/min IV for 15 minutes) and acepromazine (0.05 mg/kg IV), respectively. In the AG NIBP and IBP were recorded during regular hospital procedures.ResultsThere was a significant correlation between mean NIBP and IBP in standing (R = 0.88, P < .001) and anesthetized horses (R = 0.81, P < .001). The mean bias (lower, upper limit of agreement) was 16.4(−16.1, 48.9) mmHg for mean BP in the SG and 0.5(−22.3, 23.2) mmHg in the AG. The NIBP device was capable of identifying the increase and decrease in BP in all horses, but in the SG significant correlation between NIBP and IBP was only detected for the normotensive phase.Conclusion and Clinical ImportanceWhile the evaluated oscillometric BP device allowed estimation of BP and adequately differentiated marked trends, the accuracy and precision were low in standing horses.

Comparison of non-invasive and invasive blood pressure measurements in horses during anaesthesia using the oscillometric blood pressure monitor S/5 Datex Ohmeda

“…This is comparable to results of an early study where another monitor was evaluated in a similar study setting in horses (Branson 1997). The more recent studies using different oscillometric devices similarly showed an underestimation of MAP, SAP and DAP (Tünsmeyer et al 2015, Drynan et al 2016, Heliczer et al 2016, Olsen et al 2016). …”

“…have been evaluated revealing various results concerning the reliability of the different methods in different species (Riebold andEvans 1985, Bailey et al 1994). Oscillometric blood pressure measurement is commonly used in human and small animal medicine and several non invasive blood pressure monitors have been evaluated in standing or anaesthetised horses recently (Hatz et al 2015, Tünsmeyer et al 2015, Drynan et al 2016, Heliczer et al 2016, Olsen et al 2016 In the present study, overall the non-invasive blood pressure measurement underestimated MAP, SAP and DAP compared to the invasive measurement. In the medical field, European recommendations define 5 mmHg as very accurate, 6 -10 mmHg as slightly inaccurate, 11-15 mmHg as modera- tely inaccurate and >15 mmHg as very inaccurate (O'Brien et al 2002).…”

“…Accuracy (bias) in the other oscillometric devices evaluated recently in anaesthetised horses ranged from 0.5 -2 mmHg for MAP, while precision (SD of the difference) ranged from 10 -14 mmHg (Tünsmeyer et al 2015, Drynan et al 2016, Heliczer et al 2016). The two most common clinical settings where arterial blood pressure is measured are anaesthetised horses and standing, conscious horses with suspicion of hypertension.…”

Diagnostic value of noninvasive pulse pressure measurements in Warmblood horses with aortic regurgitation

“…The mean SAP, DAP, MAP, and HR recorded for the MR and control groups in our study were similar to the reference values reported in the veterinary medical literature using an ultrasonic blood flow detector technique and an oscillometric method . Although PP of healthy horses is only specifically reported in a single paper, reference values for PP can be deduced from other reported SAP and DAP values obtained in healthy horses and were similar to those found in our control horses . Correction for tail height above heart base is necessary to evaluate the accuracy of NIBP measurements of SAP, DAP, and MAP among different sized horses but is redundant when assessing changes in PP, because both SAP and DAP will change by the same magnitude in a given horse.…”

Pharmacokinetic and pharmacodynamic properties of orally administered torsemide in healthy horses

“…Blood samples were collected at 8 am daily for determination of packed cell volume (PCV), total protein (TP) concentration, and serum biochemical profiles. Mean arterial pressure (MAP) was measured with a tail cuff using an oscillometric monitor device (SurgiVet Advisor [Smiths Medical, Norwell, Massachusetts]) as previously described . Mean arterial pressure was measured daily at T = 0 (before drug administration), and 1, 5, and 9 hours after drug administration.…”