Table 2.
Comparison of ultrasound measured SCV and IVC parameters between the two groups
| Parameters | Total (n=132) | Hypotension |
Mean difference (95% CI) | P | |
|---|---|---|---|---|---|
| Yes (n=57) | No (n=75) | ||||
| SCV quiet breathing | |||||
| Max diameter (cm) | 0.97±0.20 | 0.98±0.22 | 0.96±0.18 | 0.02 (-0.09-0.05) | 0.53 |
| Min diameter (cm) | 0.84±0.22 | 0.82±0.25 | 0.86±0.19 | -0.04 (-0.04-0.11) | 0.30 |
| Collapsibility index (%) | 14.36±10.64 | 17.88±12.79 | 11.69±7.73 | 6.19 (−9.74-2.64) | 0.001 |
| SCV deep breathing | |||||
| Max diameter (cm) | 0.98±0.20 | 0.99±0.22 | 0.97±0.18 | 0.02 (-0.25-0.19) | 0.43 |
| Min diameter (cm) | 0.61±0.27 | 0.56±0.29 | 0.65±0.25 | -0.09 (0.00-0.18) | 0.05 |
| Collapsibility index (%) | 39.51±21.02 | 46.33±21.91 | 34.32±18.86 | 12.01 (-19.04-4.97) | 0.001 |
| IVC quiet breathing | |||||
| Max diameter (cm) | 1.88±0.4 | 1.76±0.3 | 1.97±0.4 | -0.21 (0.08-0.33) | 0.001 |
| Min diameter (cm) | 1.31±0.4 | 1.13±0.3 | 1.46±0.4 | -0.33 (0.19-0.46) | 0.001 |
| Collapsibility index (%) | 30.63±14.6 | 35.32±13.9 | 27.06±14.3 | 8.26 (-13.16--3.35) | 0.001 |
| IVC deep breathing | |||||
| Max diameter (cm) | 1.91±0.38 | 1.79±0.35 | 1.99±0.38 | -0.19 (0.07 to 0.32) | 0.003 |
| Min diameter (cm) | 0.91±0.45 | 0.77±0.48 | 1.02±0.39 | -0.25 (0.10 to 0.40) | 0.001 |
| Collapsibility index (%) | 54.20±18.06 | 60.19±18.03 | 49.64±16.82 | 10.55 (-16.58-−4.52) | 0.001 |
Data is expressed as mean±SD. Values in bold denote significant P. CI=Confidence interval, IVC=Inferior vena cava, SCV=Subclavian vein, SD=Standard deviation