Table 5.
ROC curves characteristics for heart rate variability parameters and selected physiological characteristics in never-weaned patients.
| SD2/SD1 during SBT | SampEn during SBT | ShanEn during SBT | BMI admission | P0.1 before SBT | HR during SBT | |
|---|---|---|---|---|---|---|
| AUC | 0.74 [0.50, 0.97] | 0.74 [0.50, 0.99] | 0.74 [0.52, 1.0] | 0.52 [0.32, 0.73] | 0.74 [0.39, 1.0] | 0.57 [0.37, 0.77] |
| Youden’s J | 0.52 | 0.59 | 0.50 | 0.20 | 0.63 | 0.24 |
| Sensibility | 0.86 [0.06,0.87] | 0.86 [0.03,0.94] | 0.71 [0.07,0.96] | 0.44 [0.25, 0.84] | 0.80 [0, 1.0] | 0.3 [0.48, 0.99] |
| Specificity | 0.66 [0.43, 1.0] | 0.73 [0.14, 1.0] | 0.79 [0.29, 1.0] | 0.75 [0, 0.7] | 0.84 [0.4, 1.0] | 0.94 [0, 0.6] |
| Cut-off | 1.50 | 1.63 | 2.96 | 22.7 | 2.5 | 69.5 |
| PPV | 0.14 [0.11, 0.67] | 0.17 [0.12, 0.64] | 0.18 [0.11, 0.60] | 0.12 [0.07, 0.21] | 0.27 [0.16, 0.6] | 0.30 [0.10, 0.58] |
| NPV | 0.99 [0.96, 1.0] | 0.99 [0.96, 1.0] | 0.98 [0.96, 1.0] | 0.95 [0.94, 1.0] | 0.98 [0.95, 1.0] | 0.94 [0.93, 1.0] |
AUC: area under the curve; PPV: positive predictive value; NPV: negative predictive value; SBT: spontaneous breathing test; SD1: Poincaré plot standard deviation perpendicular the line of identity; SD2: Poincaré plot standard deviation along the line of identity; SampEn: sample entropy; ShanEn: Shanon entropy: Youden’s J: statistic value for performance of dichotomous diagnostic test: Cut-off: best value for the parameter, determined by ROC curve analysis.