Table 3.
Counts and percentages of adverse events
| Standard oxygen therapy N = 56a |
High-flow nasal cannula oxygen therapy or non-invasive ventilation N = 49b |
Invasive mechanical ventilation N = 378 |
p valuec | |
|---|---|---|---|---|
| Highest grade of adverse event reachedd | ||||
| Grade 0 (no adverse event) | 4 (7.1) | 8 (16.3) | 56 (14.8) | 0.27 |
| Grade 1 | 6 (10.7) | 1 (2) | 44 (11.6) | 0.12 |
| Grade 2 | 30 (53.6) | 23 (46.9) | 244 (64.6) | 0.025 |
| Grade 3 | 15 (26.8) | 9 (18.4) | 19 (5) | < 0.001 |
| Grade 4 | 1 (1.8) | 7 (14.3) | 3 (0.8) | < 0.001 |
| Grade 5 (death within 24 h) | 0 | 1 (2) | 12 (3.2) | 0.37 |
| Grade reached = 3 or higher | 16 (28.6) | 17 (34.7) | 34 (9) | < 0.001 |
| Details of adverse events | ||||
| Modification in respiratory supporte | 17 (30.4) | 29 (59.2) | 178 (47.1) | 0.01 |
| Including tracheal intubation | 1 (1.7) | 8 (16.3)f | – | 0.01 |
| Events during BAL procedure | ||||
| Agitation | 4 (7.1) | 0 | 6 (1.6) | 0.01 |
| Respiratory distressg | 8 (14.3) | 4 (8.2) | 13 (3.4) | < 0.01 |
| Bronchospasm | 2 (3.6) | 0 | 4 (1.1) | 0.20 |
| Cough | 12 (21.4) | 4 (8.2) | 10 (2.6) | < 0.01 |
| Laryngospasm | 0 | 1 (2) | – | 0.47 |
| Significant drop in SpOh2 | 14 (25) | 2 (4.1) | 48 (12.7) | < 0.01 |
| Arrhythmia or tachycardia ≥ 150 b./min | 0 | 0 | 2 (0.5) | 0.76 |
| Hypotension (systolic BP < 90 mmHg) | 0 | 0 | 16 (4.2) | 0.10 |
| Hypertension (systolic BP > 180 mmHg) | 2 (3.6) | 2 (4.1) | 10 (2.6) | 0.81 |
| Epistaxis | 1 (1.8) | 0 | 0 | 0.02 |
| Vomiting | 2 (3.6) | 0 | 0 | < 0.01 |
| Mild bronchial hemorrhage | 1 (1.8) | 2 (4.1) | 6 (1.6) | 0.48 |
| Severe bradycardia | 0 | 0 | 1 (0.3) | 0.87 |
| Cardiac arrest | 0 | 0 | 1 (0.3) | 0.87 |
| Events within 24 h after BAL | ||||
| 1 °C rise in body temperature | 10 (17.9) | 11 (22.4) | 82 (21.7) | 0.79 |
| Body temperature increase above 38.5 °C | 9 (16.1) | 12 (24.5) | 52 (13.8) | 0.14 |
| Agitation | 1 (1.8) | 0 | 7 (1.9) | 0.63 |
| Significant drop in SpOh2 | 9 (16.1) | 5 (10.2) | 46 (12.2) | 0.63 |
| Tachycardia ≥ 150 b./min | 1 (1.8) | 1 (2) | 11 (2.9) | 0.85 |
| Hypotension (systolic BP < 90 mmHg) | 12 (21.4) | 14 (28.6) | 132 (34.9) | 0.11 |
| Hypertension (systolic BP > 180 mmHg) | 5 (8.9) | 3 (6.1) | 13 (3.4) | 0.14 |
| Need of ECMO therapy | 0 | 0 | 13 (3.4) | 0.20 |
| Death | 0 | 1 (2) | 12 (3.2) | 0.37 |
BAL bronchoalveolar lavage, BP blood pressure, ECMO extracorporeal membrane oxygenation
aIncluding 45 (80.4%) patients under oxygen therapy via standard nasal cannula or non-rebreathing mask, and 11 patients (19.6%) under oxygen therapy via rebreathing mask
bIncluding only four patients (8.2%) under non-invasive ventilation
cGroups were compared using χ2 test or Fisher exact test. p values were not adjusted for multiple testing and should be considered exploratory
dSee Table 1 for definitions of grades of adverse events
eSee text for definitions
fIncluding seven intubations in patients under nasal high-flow oxygen therapy and one in the four patients under non-invasive ventilation
g“Respiratory distress” as declared by the investigators. In all cases, “respiratory distress” needed modification of the respiratory support (see “Methods” section for definition)
hDrop in SpO2 as declared by the investigators. In all cases, drop in SpO2 needed modification of the respiratory support (see “Methods” section for definition)