Intervention (n=81) | Standard care (n=80) | P value | |
Age (years) | 58.5 (49.2, 67.0) | 59.1 (49.4, 67.5) | 0.57 |
Female—N (%) | 31 (38%) | 32 (40%) | 0.82 |
Dependency prior to hospital admission—N (%) | 0.56 | ||
Able to live without assistance | 60 (86%) | 62 (91%) | |
Minor assistance | 9 (13%) | 5 (7%) | |
Major assistance | 1 (1%) | 1 (1%) | |
Total assistance | 0 (0%) | 0 (0%) | |
Predicted body weight (kg)* | 66.0 (56.9, 74.2) | 66.0 (57.0, 72.4) | 0.95 |
ICU admission diagnostic category—N (%)† | |||
Respiratory | 67 (84%) | 67 (84%) | 1.00 |
Sepsis | 30 (38%) | 35 (44%) | 0.42 |
Cardiovascular | 17 (21%) | 17 (21%) | 1.00 |
Kidney | 14 (18%) | 15 (19%) | 0.84 |
Gastrointestinal | 13 (16%) | 14 (18%) | 0.83 |
Central nervous system | 6 (8%) | 7 (9%) | 0.77 |
Other | 6 (8%) | 2 (3%) | 0.15 |
Toxicology | 6 (8%) | 4 (5%) | 0.51 |
Haematology | 1 (1%) | 1 (1%) | 1.00 |
Orthopaedic | 3 (4%) | 3 (4%) | 1.00 |
ARDS present at enrolment‡ | 42/79 (53%) | 44/80 (55%) | 0.82 |
Aetiology of ARDS—N (%)‡ | |||
Pneumonia | 32 (76%) | 32 (73%) | 0.71 |
Sepsis | 19 (45%) | 18 (41%) | 0.69 |
Gastric content aspiration | 4 (10%) | 5 (11%) | 0.78 |
Other | 4 (10%) | 4 (9%) | 0.95 |
Pancreatitis | 1 (2%) | 5 (11%) | 0.10 |
Thoracic trauma | 0 (0%) | 1 (2%) | 0.33 |
Smoke/toxin inhalation | 2 (5%) | 1 (2%) | 0.53 |
APACHE II Score at ICU admission§ | 17 (14, 22) | 19 (16, 22) | 0.08 |
SOFA Score¶ | 9 (8, 11) n=78 | 10 (8, 12) n=76 | 0.61 |
Mode of ventilation—N (%) | 0.20 | ||
Mandatory | 68 (84%) | 66 (83%) | |
Mandatory and spontaneous breaths | 9 (11%) | 5 (6%) | |
Spontaneous | 4 (5%) | 9 (11%) | |
Adjunctive ventilatory therapies—N (%) | |||
Neuromuscular blocking drugs | 42 (52%) | 37 (46%) | 0.48 |
Prone positioning | 6 (7%) | 4 (5%) | 0.53 |
Inhaled nitric oxide | 1 (1%) | 0 (0%) | 0.32 |
Nebulised epoprostenol | 1 (1%) | 2 (3%) | 0.55 |
Tidal volume (mL/kg PBW)undefined | 6.2 (5.7, 7.1) | 6.3 (5.8, 7.4) | 0.64 |
Respiratory rate (breaths/min) | 24 (20, 26) | 24 (20, 28) | 0.38 |
PEEP (cm H2O) | 10 (9, 12) n=80 | 10 (8, 14) n=80 | 0.84 |
Plateau pressure (cm H2O) | 25 (22, 27) n=61 | 26 (24, 30) n=60 | 0.08 |
Driving pressure (cm H2O)undefined | 13 (11, 17) n=60 | 14 (12, 18) n=60 | 0.09 |
PaO2/FiO2 ratio (mm Hg)undefined | 118.5 (96.8, 136.5) n=79 | 111.8 (92.3, 130.5) n=79 | 0.19 |
PaCO2 (mm Hg) | 54.8 (47.3, 62.3) n=79 | 52.9 (47.2, 60.5) n=78 | 0.67 |
pH | 7.33 (7.27, 7.39) n=79 | 7.31 (7.25, 7.38) n=78 | 0.16 |
Baseline clinical data were collected in the 24 hours prior to randomisation unless stated otherwise. If more than one value was available for this 24-hour period, the value closest but prior to the time of randomisation was recorded.
Data presented as median (IQR) unless otherwise stated. Where median (IQR) presented, p value is from a Wilcoxon rank sum. Where, N (%) presented, p value is from a χ2 test.
*The predicted body weight of male patients was calculated as equal to 50+0.91 (centimetres of height—152.4); that of female patients was calculated as equal to 45.5+0.91 (centimetres of height—152.4).
†Patients may have had more than one admission diagnostic category or cause of ARDS identified.
‡The presence of ARDS was assessed by the treating physician.
§Scores on the Acute Physiology and Chronic Health Evaluation (APACHE) II range from 0 to 71, with higher scores indicating greater severity of illness.
¶Scores on the Sequential Organ Failure Assessment (SOFA) scale range from 0 to 24, with higher scores indicating greater severity of disease.
**Tidal volume represents the pre-randomisation value.
††Driving Pressure = Plateau Pressure − PEEP.
‡‡Second qualifying PaO2/FiO2 ratio.
APACHE, Acute Physiology and Chronic Health Evaluation; ARDS, acute respiratory distress syndrome; FiO2, fraction of inspired oxygen; ICU, intensive care unit; PaCO2, partial pressure of arterial carbon dioxide; PaO2, partial pressure of arterial oxygen; PBW, Predicted Body Weight; PEEP, positive end-expiratory pressure; SOFA, Sequential Organ Failure Assessment.