Table 1 Characteristics and outcomes of the overall cohort of patients treated with noninvasive ventilation for de novo acute hypoxemic respiratory failure
Not immunocompromised (n = 137) | Immunocompromised (n = 71) | p value | |
|---|---|---|---|
Demographic characteristics | |||
Age, years | 64 (51–76) | 56 (47–67) | 0.08 |
Gender, male, n (%) | 88 (64%) | 50 (70%) | 0.46 |
Simplified acute physiology score II | 34 (27–42) | 40 (33–49) | 0.001 |
Risk factor for acute respiratory failure, n (%) | 0.46 | ||
Pulmonary | 103 (75%) | 59 (83%) | |
No risk factor | 19 (14%) | 9 (13%) | |
Extrapulmonary | 15 (11%) | 3 (4.2%) | |
Bilateral lung infiltrates, n (%) | 103 (75%) | 67 (94%) | 0.001 |
Under oxygen | |||
Glasgow score | 15 (15–15) | 15 (15–15) | 0.19 |
Systolic blood pressure, mmHg | 128 (110–144) | 130 (116–141) | 0.97 |
Heart rate, per min | 105 (92–120) | 110 (99–124) | 0.15 |
Respiratory rate, per min | 31 (27–36) | 32 (28–37) | 0.33 |
Oxygen flow, L/min | 15 (10–15) | 12 (6–15) | 0.29 |
PaO2/FiO2, mmHg | 122 (89–176) | 135 (96–194) | 0.54 |
PaCO2, mmHg | 36 (31–39) | 34 (31–37) | 0.28 |
pH | 7.44 (7.41–7.47) | 7.46 (7.42–7.48) | 0.43 |
Under noninvasive ventilation after 1 h | |||
Pressure support, cm H2O | 8 (6–9) | 8 (7–10) | 0.02 |
Positive end-expiratory pressure, cm H2O | 5 (5–5) | 5 (5–5) | 0.56 |
FiO2, % | 70 (50–100) | 80 (53–100) | 0.056 |
SpO2, % | 97 (95–99) | 98 (96–100) | 0.052 |
Respiratory rate, per min | 30 (24–35) | 30 (24–39) | 0.19 |
Expired tidal volume, mL | 577 (471–662) | 622 (526–764) | 0.07 |
Minute ventilation, L/min | 16.3 (13.2–20.2) | 19.2 (15.3–24.0) | 0.02 |
PaO2/FiO2, mmHg | 164 (114–230) | 181 (121–261) | 0.24 |
< 150 mmHg, n (%) | 52/121 (43%) | 27/70 (39%) | 0.66 |
PaCO2, mmHg | 36 (32–40) | 35 (30–40) | 0.33 |
pH | 7.43 (7.39–7.47) | 7.45 (7.40–7.49) | 0.56 |
Under noninvasive ventilation within the first 24 h after ICU admission | |||
Worst PaO2/FiO2, mmHg | 130 (98–182) | 130 (91–181) | 0.91 |
< 150 mmHg, n (%) | 71/123 (58%) | 46/70 (66%) | 0.35 |
Acute respiratory distress syndrome, n (%) | 99 (72%) | 63 (89%) | 0.01 |
Outcomes | |||
Intubation, n (%) | 59 (43%) | 43 (61%) | 0.02 |
Time to intubation, h | 5 (2–21) | 6 (2–48) | 0.22 |
ICU mortality, n (%) | 20 (15%) | 27 (38%) | 0.0003 |
ICU mortality of intubated patients | 20/59 (37%) | 27/43 (63%) | 0.007 |
ICU length of stay, day | 9 (6–16) | 9 (6–17) | 0.96 |