Table 1.
Demographic, Radiographic, and Respiratory Characteristics of the Study Population on Admission to the ICU
| Variable | Total Population (n = 63) | COVID-19–related ARDS (n = 24) | Non–COVID-19–related ARDS (n = 39) | P Value | |
|---|---|---|---|---|---|
| Demographic variables | |||||
| Age, yr | 61 (51–69) | 67 (58–76) | 59 (49–66) | 0.02 | |
| Sex, male | 42 (67) | 19 (79) | 23 (59) | 0.10 | |
| Body mass index, kg/m2 | 28.7 (24.6–35.0) | 31.0 (27.7–34.8) | 28.2 (23.8–35.0) | 0.08 | |
| Time between symptom onset and ICU admission, d | 6 (1–10) | 8 (6–12) | 2 (0–6) | 0.001 | |
| Time between symptom onset and orotracheal intubation, d | 7 (3–12) | 10 (7–15) | 5 (0–7) | 0.0001 | |
| Comorbidities | |||||
| Chronic lung disease | 23 (37) | 8 (33) | 15 (39) | 0.68 | |
| Chronic cardiovascular disease | 28 (44) | 14 (58) | 14 (36) | 0.08 | |
| Diabetes | 14 (22) | 9 (38) | 5 (13) | 0.03 | |
| Obesity | 26 (41) | 14 (58) | 12 (31) | 0.04 | |
| Immunocompromise | 19 (30) | 2 (8) | 17 (44) | 0.004 | |
| Computed tomography findings | 53 (84) | 18 (75) | 35 (90) | ||
| Diffuse pattern | 33 (62) | 16 (89) | 20 (57) | 0.03 | |
| Focal pattern | 14 (26) | 2 (11) | 12 (34) | 0.10 | |
| Ground-glass opacity | 31 (58) | 15 (63) | 16 (46) | 0.01 | |
| Alveolar consolidation | 32 (60) | 11 (61) | 21 (60) | >0.99 | |
| Pleural effusion | 28 (53) | 3 (17) | 25 (78) | 0.0003 | |
| Pulmonary embolism | 2 (4) | 2 (17) | 0 (0) | 0.22 | |
| Respiratory physiology | |||||
| FiO2, % | 80 (70–100) | 100 (70–100) | 80 (60–100) | 0.06 | |
| PaO2/FiO2 ratio, mm Hg | 104 (81–126) | 101 (81–126) | 106 (81–124) | 0.64 | |
| Severe ARDS | 32 (51) | 12 (50) | 20 (51) | 0.92 | |
| Moderate ARDS | 31 (49) | 12 (50) | 19 (49) | 0.92 | |
| pH | 7.33 (7.26–7.39) | 7.34 (7.31–7.39) | 7.31 (7.23–7.39) | 0.24 | |
| PaCO2, mm Hg | 45.0 (39.5–52.0) | 43.1 (40.3–50.7) | 46.0 (39.5–53.0) | 0.51 | |
| Ventilatory ratio | 1.91 (1.65–2.33) | 1.89 (1.67–2.23) | 1.99 (1.64–2.55) | 0.46 | |
| Vt, ml/kg of predicted body weight | 6.07 (5.71–6.45) | 6.07 (5.95–6.16) | 6.09 (5.36–6.80) | 0.74 | |
| Plateau pressure, cm H2O | 26.0 (23.0–28.0) | 26.0 (21.8–28.0) | 26.0 (23.5–29.0) | 0.29 | |
| PEEP applied, cm H2O | 10.0 (8.5–14.0) | 12.0 (6.5–15.0) | 10.0 (9.5–13.0) | 0.85 | |
| Driving pressure, cm H2O | 14.0 (11.0–17.0) | 13.0 (10.0–15.0) | 15.0 (12.0–17.5) | 0.12 | |
| Crs, ml/cm H2O | 30.0 (23.0–39.5) | 32.5 (25.8–41.3) | 29.0 (22.0–37.0) | 0.13 |
Definition of abbreviations: ARDS = acute respiratory distress syndrome; COVID-19 = coronavirus disease; Crs = respiratory system compliance; PEEP = positive end-expiratory pressure.
All measurements were made in the absence of inhaled nitric oxide, in the supine position, and before lung recruitment maneuvers.
Data are shown as n (%) or median (interquartile range). Bold values indicate a statistically significant difference with a P value < 0.05.