Zupancich 2005.

Methods	RCT with parallel groups Approved by the institutional review board and informed consents obtained Site: Università di Torino, Ospedale S. Giovanni Battista, Turin, Italy Setting: university hospital Dates of data collection: not reported
Participants	40 participants undergoing elective coronary artery bypass graft Exclusion criteria: presence of cardiogenic pulmonary oedema, emergency or urgent cases, pre‐existing chronic obstructive pulmonary disease, smoking history, major chest wall abnormalities and enrolment in other studies
Interventions	Treatment group: tidal volume 8 mL/kg and PEEP 10 cmH2O after CPB disconnection (n = 20) Control group: tidal volume 10–12 mL/kg and PEEP 2–3 cmH2O after CPB disconnection (n = 20) In both ventilatory strategies, FiO2 0.5, inspiratory/expiratory ratio 1:2 and respiratory rate 12–15 breaths/min
Outcomes	Relevant to this review Death (period of follow‐up unspecified) Others Interleukin‐6 and ‐8
Notes	Funding: supported by a grant from the Italian Minister of University and Research (02‐02548) and from the National Research Council (99‐9854) Declaration of interest: none mentioned Volume per body weight: measured body weight
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Quote: "randomly assigned"
Allocation concealment (selection bias)	Unclear risk	Not mentioned
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Not mentioned
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Not mentioned
Incomplete outcome data (attrition bias) All outcomes	Low risk	Quote: "protocol withdrawal occurred with any of the following a priori conditions: need for levels of dobutamine or dopamine of greater than 5 mcg/kg/min, haemodynamically unstable condition with positive end‐expiratory pressure, or major cardiac arrhythmia." but "no patients had to be excluded from the study."
Selective reporting (reporting bias)	Low risk	All results provided
Other bias	Low risk	Groups well balanced

ARDS: adult respiratory distress syndrome; ASA: American Anesthesiologists Society physical status classification; BMI: body mass index; cm: centimetre; CPB: cardiopulmonary bypass; cmH₂O = centimetres of water; dL: decilitre; FiO₂: inspired fraction of oxygen; IBW: ideal body weight; ICU: intensive care unit; kg/m²: kilogram per square metre of body surface area; kPa: kiloPascal; min: minute; mg: milligram; mL/kg: millilitres per kilogram of body weight; mmHg: millimetres of mercury; mmol: millimoles; n: number of participants; PaO₂: arterial oxygen partial pressure; PEEP: positive end‐expiratory pressure; PaCO₂: arterial carbon dioxide partial pressure; pH: hydrogen ion concentration; RCT: randomized controlled trial; SaO₂: oxygen saturation measured by pulse oximetry; SD: standard deviation.