Talmor 2008.
| Study characteristics | ||
| Methods | Randomised controlled trial conducted in a UCI from the USA | |
| Participants | 61 participants (1 centre) Included: ALI and ARDS (AECC) Excluded: recent injury or other pathological condition of the oesophagus, major bronchopleural fistula, solid organ transplantation Sample size was estimated from considering the standard deviation to be 100 (equivalent to a coefficient of variation of 250%); on the basis of this estimate, a sample of 100 patients per group would be required to detect a difference of 40 in PaO₂/FIO₂with 80% power and a 2‐tailed α value of 0.05. Interim analyses were designed to allow early termination of the trial |
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| Interventions | In both groups ‐ control (31) and intervention (30) ‐ goals of MV included TV 6 mL/kg PBW, recruiting manoeuvre to standardise the history of lung volume, PaO₂ between 55 and 120 mmHg or SpO₂ between 88% and 98%, arterial pH of 7.30 to 7.45, and PaCO₂ of 40 to 60 mmHg PEEP Control: PEEP/FIO₂ combination, mean PEEP 10 ± 4 cmH₂O during first 72 hours Intervention: transpulmonary pressure (airway pressure minus pleural pressure) was determined, airway pressure was recorded during MV, and pleural pressure was estimated by an oesophageal balloon catheter. PEEP levels were set to achieve transpulmonary pressure of 0 to 10 cmH₂O at end‐expiration. Mean PEEP 17 ± 6 cmH₂O during first 72 hours All measurements were performed within 72 hours of patient inclusion |
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| Outcomes | Primary: improvement in arterial oxygenation (PaO₂/FIO₂) Secondary: indices of lung mechanics and gas exchange (respiratory system compliance and ratio of physiological dead space to tidal volume), VFDs, LOS in ICU, days not spent in ICU, mortality at Day 28, mortality at Day 180, days of ventilation among survivors |
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| Notes | This study was funded in part by a grant from the National Heart, Lung, and Blood Institute. Dr Malhotra received funding from Respironics. Mr Ritz received funding from INO Therapeutics. Remaining study authors have disclosed that they do not have any potential conflicts of interest | |
| Risk of bias | ||
| Bias | Authors' judgement | Support for judgement |
| Random sequence generation (selection bias) | Low risk | Patients randomly allocated because study authors used random allocation with a block randomisation scheme |
| Allocation concealment (selection bias) | Low risk | Opaque sealed envelopes that were randomly ordered |
| Blinding of participants and personnel (performance bias) All outcomes | Low risk | Incomplete blinding (blinding of participants but not of personnel) but outcomes not influenced |
| Blinding of outcome assessment (detection bias) All outcomes | Low risk | No blinding but outcomes not influenced by lack of blinding |
| Incomplete outcome data (attrition bias) All outcomes | Low risk | In the experimental group, 1 participant who could not be assessed was included in the analysis on the basis of the intention‐to‐treat principle |
| Selective reporting (reporting bias) | Low risk | Published reports included all expected outcomes |
| Other bias | Low risk | Review authors believed the study to be free of other sources of bias |