†Negative value indicates that the NIBP underestimated
the IBP in that location, and a positive value indicates an
overestimation.
Table 3. Mean and 95% confidence intervals (95% CI) of
sensitivity, specificity, false positive and false negative rates of
measuring mean arterial pressure (MAP) non-invasively via oscillometric
technique (NIBP) on the tail with a cuff width-to-tail circumference
ratio of 0.25 to detect hypotension in dorsally recumbent, anaesthetized
horses. Calculations were made using either individual heart level
corrections (A) or using a standardised 27 mmHg heart level correction
(B, C, D). True hypotension was defined as MAP < 70 mmHg in
the FA and the parameters were calculated for hypotension based on NIBP
< 70 mmHg (A, B), < 80 mmHg (C) or < 90
mmHg (D). False positive rates indicate the percentage of normotensive
(FA ≥ 70 mmHg) horses that would be considered hypotensive and hence
treated based on NIBP readings. False negative rates indicate the
percentage of truly hypotensive (FA < 70 mmHg) that would be
considered normotensive and hence not be treated based on NIBP readings.