Comparison of closed endotracheal suction versus open endotracheal suction in the development of ventilator-associated pneumonia in intensive care patients: an evaluation using meta-analytic techniques.

BACKGROUND Ventilator-associated pneumonia (VAP), a frequent nosocomial infection in the intensive care, is associated with considerable morbidity. Endotracheal suctioning is routinely performed in mechanically ventilated patients to clear secretions. This study assessed if there were advantages of closed endotracheal suctioning (CES) over open endotracheal suctioning (OES) with respect to clinical outcomes. MATERIALS AND METHODS Trials comparing CES with OES were identified by search of MEDLINE (1966-July 2006) and bibliographies of relevant articles. Only trials reporting VAP and/or mortality were considered. Studies reporting only physiological outcomes were excluded. STATISTICAL ANALYSIS USED A meta-analysis of randomized controlled trials (RCTs) was performed using the random-effects estimator. The effect of suctioning type on VAP and mortality was reported as risk difference (RD) and duration of mechanical ventilation (MV) as mean weighted difference (MWD). RESULTS Nine RCTs fulfilled criteria for inclusion. There was no differential treatment effect of suctioning type (closed versus open, n = 9 studies) on VAP (RD - 0.01; 95% CI - 0.05, 0.03; P = 0.63) or on mortality (n = 5; RD 0.01; 95% CI - 0.04, 0.05; P = 0.8). Although OES was associated with a shorter duration of MV (n = 4; MWD -0.64; 95% CI 0.21, 1.06; P = 0.004), one study contributed significantly to the estimates. Heterogeneity of treatment effects was not observed. CONCLUSIONS This meta-analysis has not demonstrated a superiority of CES over OES with respect to VAP or mortality. Thus the decision for the use of CES may be based on possible benefits in patients requiring high respiratory supports, reduced costs in those needing prolonged MV or occupational health and safety concerns with OES.