TABLE 4.
Unadjusted and adjusted linear regression analysis of the associations between each preoperative SBP dynamical metric and postoperative number of hours in the ICU.
| A. Sub-group with STS (N = 340) | |||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Model 0: Unadjusted | Model 1: Age and Sex | Model 2: STS | |||||||||||||
| Variable | ß | 95% CI | p value | R-squared | ß | 95% CI | p value | R-squared | ß | 95% CI | p value | R-squared | |||
| BPF (%) | 0.21 | 0.11 | 0.30 | < 0.001 | 0.045 | 0.16 | 0.04 | 0.27 | 0.007 | 0.066 | 0.10 | 0.00 | 0.20 | 0.046 | 0.110 |
| Mean SBP (mmHg) | 0.02 | −0.10 | 0.14 | 0.705 | 0.001 | 0.00 | −0.12 | 0.12 | 0.953 | 0.043 | 0.03 | −0.08 | 0.14 | 0.548 | 0.102 |
| SD (mmHg) | −0.04 | −0.13 | 0.05 | 0.423 | 0.001 | −0.03 | −0.12 | 0.06 | 0.473 | 0.044 | −0.01 | −0.10 | 0.08 | 0.861 | 0.101 |
| CV | −0.05 | −0.14 | 0.04 | 0.250 | 0.003 | −0.04 | −0.13 | 0.05 | 0.368 | 0.045 | −0.03 | −0.12 | 0.06 | 0.466 | 0.102 |
| ARV (mmHg) | 0.15 | 0.03 | 0.27 | 0.016 | 0.024 | 0.12 | −0.00 | 0.24 | 0.057 | 0.058 | 0.10 | −0.02 | 0.21 | 0.110 | 0.110 |
| DFA ⍺1 | −0.17 | −0.28 | −0.05 | 0.005 | 0.029 | −0.11 | −0.24 | −0.02 | 0.086 | 0.055 | −0.03 | −0.14 | 0.09 | 0.612 | 0.101 |
| STS (%) | 0.30 | 0.20 | 0.41 | < 0.001 | 0.101 | ||||||||||
| B. Group with EuroSCORE II (N = 378) | |||||||||||||||
| Model 0: Unadjusted | Model 1: Age and Sex | Model 2: EuroSCORE II | |||||||||||||
| Variable | ß | 95% CI | p value | R-squared | ß | 95% CI | p value | R-squared | ß | 95% CI | p value | R-squared | |||
| BPF (%) | 0.21 | 0.12 | 0.31 | < 0.001 | 0.046 | 0.18 | 0.07 | 0.29 | 0.001 | 0.060 | 0.15 | 0.05 | 0.24 | 0.004 | 0.081 |
| Mean SBP (mmHg) | 0.04 | −0.08 | 0.16 | 0.513 | 0.002 | 0.03 | −0.09 | 0.14 | 0.654 | 0.033 | 0.05 | −0.06 | 0.16 | 0.403 | 0.065 |
| SD (mmHg) | −0.04 | −0.12 | 0.05 | 0.423 | 0.001 | −0.04 | −0.12 | 0.05 | 0.430 | 0.034 | −0.02 | −0.11 | 0.06 | 0.586 | 0.063 |
| CV | −0.06 | −0.15 | 0.03 | 0.188 | 0.003 | −0.05 | −0.14 | 0.03 | 0.229 | 0.035 | −0.05 | −0.14 | 0.04 | 0.242 | 0.065 |
| ARV (mmHg) | 0.18 | 0.03 | 0.32 | 0.016 | 0.032 | 0.16 | 0.01 | 0.31 | 0.042 | 0.057 | 0.14 | −0.01 | 0.29 | 0.077 | 0.081 |
| DFA ⍺1 | −0.17 | −0.29 | −0.06 | 0.004 | 0.030 | −0.13 | −0.27 | 0.00 | 0.045 | 0.049 | −0.08 | −0.21 | 0.05 | 0.224 | 0.068 |
| EuroSCORE II (%) | 0.25 | 0.15 | 0.35 | < 0.001 | 0.062 | ||||||||||
The values shown are the regression coefficients (ß) and 95% CIs, for standardized variables. Separate models were fitted for each of the different BPV, indicators. The adjustments were age and sex in Model 1, and STS, or EuroSCORE II, in Model 2. Statistically significant p values are highlighted in bold. Abbreviations: ARV, average real variability; BPF, blood pressure fragmentation; CI, confidence interval; CV, coefficient of variation; DFA, detrended fluctuation analysis; EuroSCORE, European System for Cardiac Operative Risk Evaluation; ICU, intensive care unit; LOS, length of stay; SBP, systolic blood pressure; SD, standard deviation; and STS, Society of Thoracic Surgeons.