Kollef 2008.
| Methods | Mulitcentre, prospective, randomized, single‐blind, controlled study | |
| Participants | Setting: 54 centres throughout North America (Canada & USA). Inclusion criteria: Adults at least 18 years old eligible for enrolment if they were expected to require mechanical ventilation with an endotracheal tube for 24 hours or longer Exclusion criteria: Participation in another study that conflicted with the current study, bronchiectasis, severe or massive haemoptysis, cystic fibrosis, pregnancy, silver sensitivity, and endotracheal intubation for longer than 12 hours within the preceding 30 days Participant numbers: 2003 randomly assigned; 494 excluded (71 not intubated, 423 intubated < 24 h); 1932 all intubated; 1509 intubated ≥ 24 h analysed. 766 silver‐coated ETT versus 743 non‐coated ETT who were intubated for ≥ 24 h | |
| Interventions | Silver‐coated ETT (7 mm to 9 mm internal diameter, high‐volume/low‐pressure) for 3.2 days versus non‐coated ETT (7 mm to 9 mm internal diameter, high‐volume/low‐pressure) for 3.2 days | |
| Outcomes | Risk of VAP; hospital mortality; device‐related adverse events; duration of intubation; time to VAP onset; length of hospital and ICU stay | |
| Notes | No differences were noted between groups in APACHE II scores, use of enteral nutrition, presence of immunodeficiency, or other risk factors for VAP Chronic obstructive pulmonary disease was more common in the group receiving the non‐coated tube (P value = 0.007) Cause of hospital mortality was not specified in this study VAP was diagnosed by clinical and radiographic parameters combined with culture‐positive fluid obtained by BAL. Explicitly, new radiographic confirmed infiltrate with qualifying clinical signs were triggers for conducting quantitative BAL No standardization of prevention strategies at the clinical sites that participated in the study |
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| Risk of bias | ||
| Bias | Authors' judgement | Support for judgement |
| Random sequence generation (selection bias) | Low risk | Computer‐generated randomization was provided in blocks of 4 |
| Allocation concealment (selection bias) | Low risk | Adequate allocation concealment with a series of sequentially numbered envelopes, each containing a randomization card for a study participant |
| Blinding of participants and personnel (performance bias) All outcomes | High risk | Investigators were blinded to block length; microbiology laboratory personnel were blinded to group assignments |
| Blinding of outcome assessment (detection bias) All outcomes | High risk | Single‐blinded study design. The ICU investigators could not be blinded |
| Incomplete outcome data (attrition bias) All outcomes | Low risk | 0% of participants lost to follow‐up |
| Selective reporting (reporting bias) | Low risk | Protocol was registered as NCT00148642, and outcomes were reported |
| Other bias | Low risk | None was apparent |