Table 4.
Physiological variables and diaphragm shear modulus according to the outcome of the spontaneous breathing trial
| SBT success (n = 12) | SBT failure (n = 13) | |||||
|---|---|---|---|---|---|---|
| Start of SBT | End of SBT | p value | Start of SBT | End of SBT | p value | |
| Clinical variables | ||||||
| Systolic AP, mmHg | 140 (129–157) | 126 (121–159) | 0.109 | 136 (124–150) | 158 (128–161) | 0.045 |
| Heat rate, min−1 | 93 (84–99) | 97 (81–103) | 0.541 | 110 (90–118) | 111 (95–121) | 0.391 |
| Breathing pattern | ||||||
| VT, mL/kg | 4.1 (3.2–5.6) | 4.1 (3.4–5.4) | 0.894 | 3.2 (2.9–3.3) | 3.5 (2.9–4.9) | 0.423 |
| Respiratory rate, cycles/min | 24 (18–34) | 25 (19–26) | 0.332 | 24 (20–29) | 32 (27–34) | 0.288 |
| Diaphragm function | ||||||
| ΔPdi, cmH2O | 5.9 (4.1–17.4) | 9.5 (5.2–12.0) | 0.777 | 20.7 (12.5–29.1) | 15.3 (8.8–27.5) | 0.570 |
| PTPdi, cmH2O.s/breath | 3.2 (1.9–10.3) | 5.7 (3.2–11.9) | 0.903 | 11.6 (9.3–15.0) | 7.9 (5.0–10.7) | 0.495 |
| PTPdi, cmH2O.s/min | 70 (47–364) | 138 (73–209) | 0.853 | 239 (187–446) | 263 (134–316) | 0.602 |
| ΔSMdi, kPa | 9.8 (7.8–13.4) | 7.4 (4.8–9.7) | 0.323 | 13.5 (8.8–15.9) | 7.6 (5.6–14.6) | 0.879 |
Results are shown as median (Q1-Q3). SBT, spontaneous breathing trial; AP, arterial pressure; VT, tidal volume; ΔPdi, inspiratory changes in transdiaphragmatic pressure; PTPdi, transdiaphragmatic pressure time product; ΔSMdi, inspiratory changes in diaphragm shear modulus