Table 2.
Ventilation settings and asynchronies recorded
| Total population (n = 61) | PSV | NAVA | p | ||||||
|---|---|---|---|---|---|---|---|---|---|
| Median | 95% CI | Minimum | Maximum | Median | 95% CI | Minimum | Maximum | ||
| Level of support | 10a | 8–12 | 3 | 24 | 0.6b | 0.5–0.8 | 0.1 | 3 | NA |
| Expiratory trigger PSV (%) | 30 | 30–35 | 15 | 50 | NA | NA | NA | NA | NA |
| Inspiratory trigger PSV (1–10) | 6 | 5–6 | 1 | 9 | NA | NA | NA | NA | NA |
| Macro-asynchronies | |||||||||
| Auto-triggering | 0 | 0–0.2 | 0 | 4.1 | 0 | 0–0.08 | 0 | 24 | 0.0182 |
| % auto-triggering | 0 | 0–0.6 | 0 | 18.4 | 0 | 0–0.19 | 0 | 24 | 0.0251 |
| Double triggering | 0.1 | 0–0.3 | 0 | 5.3 | 0.1 | 0–0.20 | 0 | 24 | 0.0223 |
| % double triggering | 0.3 | 0–0.5 | 0 | 16.6 | 0.4 | 0–0.79 | 0 | 24 | 0.0063 |
| Ineffective triggering | 0 | 0–0.08 | 0 | 14.4 | 0 | 0–0.13 | 0 | 24 | 0.4363 |
| % ineffective triggering | 0 | 0–0.19 | 0 | 33.9 | 0 | 0–0.46 | 0 | 24 | 0.3272 |
| Macro-asynchrony index (%) | 1.6 | 1–3.18 | 0 | 33.9 | 1.64 | 0.4–2.5 | 0 | 24 | 0.6420 |
| Micro-asynchronies | |||||||||
| Premature cycling-off | 0.13 | 0–0.6 | 0 | 4 | 0 | 0–0 | 0 | 24 | < 0.0001 |
| % premature cycling-off | 0.3 | 0–1.9 | 0 | 31 | 0 | 0–0 | 0 | 24 | < 0.0001 |
| Late cycling-off | 0.123 | 0–0.38 | 0 | 11.4 | 0 | 0–0 | 0 | 24 | 0.0002 |
| % late cycling-off | 0.5 | 0–1.24 | 0 | 27.7 | 0 | 0–0 | 0 | 66 | 0.0013 |
| Inspiratory trigger delay | 0.88 | 0.5–1.75 | 0 | 25.9 | 0 | 0–0.13 | 0 | 24 | < 0.0001 |
| % inspiratory trigger delay | 3.55 | 1.8–5.96 | 0 | 81.9 | 0 | 0–0.4 | 0 | 24 | < 0.0001 |
| Micro-asynchrony index (%) | 9.8 | 6.8–15.7 | 0 | 100.7 | 0.35 | 0–0.86 | 0 | 24 | < 0.0001 |
| Total asynchronies | |||||||||
| Total AI (%) | 14 | 9.9–21.7 | 0 | 101.8 | 2.1 | 0.8–3.9 | 0 | 24 | < 0.0001 |
| Patients with AI > 10% | 38 | 62.3% | 7 | 11.5% | |||||
| Respiratory rate (cycle/min) | 28 | 25–29 | 12.6 | 46 | 26 | 25–28 | 11 | 46.6 | 0.0323 |
| VT expired (ml) | 400 | 381–418 | 194.8 | 947 | 366 | 336–388 | 207.1 | 982 | 0.0020 |
| Volume/min (l/min) | 11.4 | 10–13 | 5.5 | 21.7 | 11.4 | 11–12.2 | 6 | 20.4 | 0.8953 |
| VT (ml/kg PBW) | 6.2 | 5.9–6.4 | 3.1 | 12.4 | 5.8 | 5.3–6.2 | 3.3 | 12.9 | 0.0009 |
| PEEP (cmH2O) | 6 | 5–6 | 3 | 10 | 5 | 5–5 | 3 | 10 | 0.0029 |
| Eadi peak | 15.7 | 12.4–19.7 | 3.3 | 84.75 | 15.2 | 12.5–18.2 | 6.72 | 84 | 0.1142 |
Results are expressed as medians, 95% confidence intervals (CIs) or number (%)
Significant p values are shown in bold typeface
AI asynchrony index, Eadi electrical activity of the diaphragm, NA not available, NAVA neurally adjusted ventilatory assist, PDW predicted body weight, PEEP positive end-expiratory pressure, PSV pressure support ventilation, VT tidal volume
aResults expressed in cmH2O
bResults expressed in cmH2O/μV