Table 1 Respiratory parameters and modalities of inhaled nitric oxide administration in patients with COVID-19-related acute respiratory distress syndrome receiving inhaled nitric oxide, according to the oxygenation response within 6 h
ADa | All patients N = 151 | Oxygenation response at H6 | p value | ||
|---|---|---|---|---|---|
Yes N = 69 | No N = 82 | ||||
ARDS severity at diagnosis | 111 | 0.948 | |||
Mild | 5 (5%) | 2 (4%) | 3 (5%) | ||
Moderate | 38 (34%) | 18 (33%) | 20 (35%) | ||
Severe | 68 (61%) | 34 (63%) | 34 (60%) | ||
ARDS severity within 6 h before iNO initiation | 150 | 0.002 | |||
Mild | 4 (3%) | 1 (1%) | 3 (4%) | ||
Moderate | 51 (34%) | 14 (21%) | 37 (45%) | ||
Severe | 95 (63%) | 53 (78%) | 42 (51%) | ||
ABG before iNO initiation, prone position | |||||
PaO2/FiO2 | 44 | 79 (68–95) | 79 (68–95) | 80 (69–95) | 0.953 |
PaO2, mmHg | 44 | 71 (63–80) | 71 (64–79) | 71 (60–80) | 0.879 |
FiO2, % | 44 | 100(80–100) | 100 (80–100) | 100(80–100) | 0.625 |
PaCO2, mmHg | 44 | 48 (43–60) | 46 (42–58) | 49 (44–66) | 0.250 |
pH | 44 | 7.32 (7.24–7.40) | 7.32 (7.24–7.41) | 7.35 (7.24–7.39) | 0.787 |
ABG before iNO initiation, supine position | |||||
PaO2/FiO2 | 129 | 90 (71–122) | 79 (61–99) | 109 (81–136) | < 0.001 |
PaO2, mmHg | 129 | 72 (62–87) | 68 (57–78) | 76 (67–98) | 0.001 |
FiO2, % | 129 | 90 (70–100) | 100 (71–100) | 80 (70–100) | 0.035 |
PaCO2, mmHg | 129 | 49 (40–55) | 48 (37–55) | 49 (41–56) | 0.270 |
pH | 129 | 7.36 (7.28–7.42) | 7.38 (7.28–7.42) | 7.35 (7.28–7.41) | 0.421 |
ABG before iNO initiation | |||||
PaO2/FiO2 | 151 | 86 (71–119) | 79 (64–97) | 98 (74–131) | < 0.001 |
PaO2, mmHg | 151 | 72 (64–85) | 71 (61–79) | 74 (67–90) | 0.018 |
FiO2, % | 151 | 90 (70–100) | 100 (80–100) | 80 (70–100) | 0.009 |
PaCO2, mmHg | 151 | 49 (41–58) | 48 (39–57) | 49 (43–58) | 0.246 |
pH | 151 | 7.35 (7.27–7.41) | 7.34 (7.28–7.42) | 7.35 (7.27–7.41) | 0.662 |
Time interval between | |||||
Disease onset and ICU admission, days | 147 | 8 (6–10) | 7 (6–10) | 8 (6–10) | 0.589 |
ICU admission and ARDS diagnosis, days | 141 | 0 (0–2) | 0 (0–2) | 0 (0–2) | 0.819 |
ARDS diagnosis and intubation, days | 148 | 0 (0–1) | 0 (0–1) | 0 (0–1) | 0.437 |
Intubation and iNO initiation, days | 151 | 4 (1–9) | 3 (0–8) | 5 (1–9) | 0.140 |
ICU admission and iNO initiation, days | 151 | 7 (3–12) | 7 (2–11) | 7 (4–12) | 0.489 |
Ventilatory status | |||||
Intubated within 24 h after ICU admission | 148 | 78 (53%) | 38 (56%) | 40 (50%) | 0.475 |
Intubated after iNO initiation | 151 | 1 (0.7%) | 1 (1–0.4%) | 0 (0.0%) | 0.457 |
Prone position before iNO initiation | 151 | 99 (65.6%) | 42 (60.9%) | 57 (69.5%) | 0.266 |
Number of prone position sessions before iNO initiation | 97 | 2 (1–3) | 1 (1–3) | 2 (1–3) | 0.502 |
Almitrine at time of iNO administration | 151 | 31 (20.5%) | 16 (23.2%) | 15 (18.3%) | 0.4581 |
Ventilation parameters at iNO initiation | |||||
Respiratory rate, cpm | 145 | 28 (24–30) | 27 (24;30) | 29 (24;32) | 0.247 |
Plateau pressure, cmH2O | 107 | 28 (25–31) | 28 (25–31) | 27 (22–30) | 0.115 |
FiO2 (%) | 145 | 98 (70–100) | 99 (80–100) | 90 (70–100) | 0.333 |
Positive end expiratory pressure, cmH2O | 143 | 12 (9–14) | 12 (10–14) | 12 (8–14) | 0.528 |
Tidal volume, mL/kg PBW | 132 | 6.1 (5.8–6.8) | 6.2 (5.5–7.1) | 6.1 (5.9–6.5) | 0.578 |
iNO modalities | |||||
iNO dosage at initiation, ppm | 140 | 10 (7–13) | 10 (7–13) | 10 (6–13) | 0.905 |
Monitoring of nitric dioxide | 151 | 33 (22%) | 14 (20%) | 19 (23%) | 0.670 |
Duration of iNO administration, days | 149 | 3.1 (1.4–6.5) | 4.2 (1.8,7.0) | 2.7 (1.2,5.3) | 0.073 |
Type of ventilation device | 121 | 0.542 | |||
Continuous delivery (Minikinox-type) | 69 (57.0%) | 34 (61.8%) | 35 (53.0%) | ||
Sequential mode (Optikinox) | 32 (26.4%) | 12 (21.8%) | 20 (30.3%) | ||
Synchronized with ventilators | 20 (16.5%) | 9 (16.4%) | 11 (16.7%) | ||