Skip to main content
. 2014 Jun 12;2014(6):CD007922. doi: 10.1002/14651858.CD007922.pub3

Choi 2006.

Methods Parallel randomized controlled trial
High risk of bias
Participants

  1. 46 participants randomly assigned

  2. 40 participants completed the trial protocol

  3. Included: adults scheduled for surgery of at least 5 hours' duration

  4. Excluded: history of lung disease, immunosuppressive medications, recent infection, recent ICU admission, previous thromboembolic disease

  5. Age: years (mean 62 ± 9.8, 61 ± 9.5)

  6. Sex distribution: M/F (14/7, 14/5)

  7. Country: Netherlands
Interventions

  1. 21 participants received PEEP (10 cm H2O), commenced post induction

  2. 19 participants received ZEEP
Outcomes

  1. Mortality during admission

  2. Pneumonia during admission

  3. Mechanical respiratory support during admission
Notes Single centre
Mortality was not specifically described as an outcome. 1 death was described; it was stated clearly that all other participants in the trial were discharged home
Could be included in the following subgroup analyses: PEEP 10 cm H2O
Risk of bias
Bias Authors' judgement Support for judgement
Random sequence generation (selection bias) High risk Quote: "...Randomization was performed by drawing a presealed envelope..."
Comment: inadequate sequence generation
Allocation concealment (selection bias) High risk Quote: as above
Comment: sealed envelopes, but allocation concealment would have been compromised towards the end, given the randomization technique
Blinding of participants and personnel (performance bias) 
 Mortality Unclear risk Not described
Blinding of participants and personnel (performance bias) 
 Oxigen efficiency ‐ PaO2/FiO2 Unclear risk Not described
Blinding of participants and personnel (performance bias) 
 Atelectasis Unclear risk Not described
Blinding of outcome assessment (detection bias) 
 Mortality Unclear risk Not described
Blinding of outcome assessment (detection bias) 
 Oxigen efficiency ‐ PaO2/FiO2 Unclear risk Not described
Blinding of outcome assessment (detection bias) 
 Atelectasis Unclear risk Not described
Incomplete outcome data (attrition bias) 
 All outcomes Low risk All randomly assigned participants analysed
Selective reporting (reporting bias) High risk Mortality not described in methods section