Table 1. Baseline Participant Characteristics.
| Characteristics | Lower oxygenation (n = 362)a | Higher oxygenation (n = 358)a |
|---|---|---|
| Age, median (IQR), y | 65 (54-73) | 66 (57-76) |
| Sex, No. (%) | ||
| Female | 109 (30.1) | 116 (32.4) |
| Male | 253 (69.9) | 242 (67.6) |
| Interval between hospital admission and randomization, median (IQR), d | 2 (1-4) | 2 (1-4) |
| Interval between intensive care unit admission and randomization, median (IQR), h | 3 (1-7) | 3 (1-7) |
| Coexisting illness, No. (%) | ||
| Ischemic heart disease | 38 (10.5) | 34 (9.5) |
| Chronic obstructive pulmonary disease | 28 (7.7) | 24 (6.7) |
| Active hematological malignancy | 26 (7.2) | 35 (9.8) |
| Long-term dialysis | 9 (2.5) | 8 (2.2) |
| Active metastatic cancer | 8 (2.2) | 8 (2.2) |
| Type of admission, No. (%) | ||
| Medical | 361 (99.7) | 357 (99.7) |
| Elective surgical | 0 | 0 |
| Emergency surgical | 1 (0.3) | 1 (0.3) |
| Acute illness, No. (%) | ||
| Pneumonia | 265 (73.2) | 258 (72.1) |
| Acute respiratory distress syndrome | 149 (41.2) | 144 (40.2) |
| Myocardial infarction | 7 (1.9) | 1 (0.3) |
| Cardiac arrest | 2 (0.6) | 5 (1.4) |
| Hemorrhagic or ischemic stroke | 1 (0.3) | 2 (0.6) |
| Intestinal ischemia | 2 (0.6) | 0 |
| Multiple trauma | 1 (0.3) | 0 |
| Invasive ventilation | ||
| Patients, No. (%) | 90 (24.9) | 82 (22.9) |
| Tidal volume, median (IQR), mL | 520 (450-608) | 515 (470-595) |
| End-expiratory pressure, median (IQR), cm H2O | 12 (10-14) | 12 (9-12) |
| Peak pressure, median (IQR), cm H2O | 25 (23-28) | 25 (25-28) |
| Noninvasive ventilation or CPAP | ||
| Patients, No. (%) | 41 (11.3) | 52 (14.5) |
| End-expiratory pressure, median (IQR), cm H2O | 8 (6-9) | 8 (6-9) |
| Treatment in an open system, No. (%) | 231 (63.8) | 224 (62.6) |
| Pao2, median (IQR), mm Hg | 70 (62-80) | 71 (62-84) |
| Sao2, median (IQR), % | 94 (91-96) | 94 (91-96) |
| Fio2, median (IQR)b | 0.80 (0.61-1.00) | 0.80 (0.62-1.00) |
| Pao2:Fio2 ratio, median (IQR) | ||
| In all systems | 91 (71-122) | 96 (74-124) |
| In closed systems | 99 (75-148) | 109 (80-149) |
| Lactate level, median (IQR), mmol/L | 1.4 (1-1.9) | 1.4 (1-2) |
| Lowest mean arterial pressure, median (IQR), mm Hgc | 72 (62-84) | 71 (62-83) |
| Use of vasopressors | ||
| Patients, No. (%) | 82 (22.7) | 69 (19.3) |
| Highest dose of norepinephrine, median (IQR), μg/kg/mind | 0.13 (0.07-0.34) | 0.12 (0.06-0.29) |
| SOFA scoree | 3 (2-5) [n = 357] | 3 (2-6) [n = 352] |
Abbreviations: CPAP, continuous positive airway pressure; Sao2, arterial oxygen saturation; Fio2, fraction of inspired oxygen.
a
Data on all baseline characteristics were missing for 3 patients in each group.
b
Fio2 in open systems was estimated using standardized conversion tables. See eTable 1 in Supplement 2.
c
Lowest median value of the mean arterial pressure recorded during the 24 hours before randomization.
d
In patients receiving norepinephrine at baseline.
e
Scores on the Sequential Organ Failure Assessment (SOFA) range from 0 to 24, with higher scores indicating more severe organ failure. Definitions of SOFA scoring in the HOT-COVID trial and single components of the baseline SOFA score are available in eTables 2 and 3 in Supplement 2.