Intermittent Subglottic Secretion Drainage and Ventilator-associated Pneumonia: A Multicenter Trial

Abstract

RATIONALE: Ventilator-associated pneumonia (VAP) causes substantial morbidity and mortality. The influence of subglottic secretion drainage (SSD) in preventing VAP remains controversial. OBJECTIVES: To determine whether SSD reduces the overall incidence of microbiologically confirmed VAP. METHODS: Randomized controlled clinical trial conducted at four French centers. A total of 333 adult patients intubated with a tracheal tube allowing drainage of subglottic secretions and expected to require mechanical ventilation for ≥48 hours was included. Patients were randomly assigned to undergo intermittent SSD (n = 169) or not (n = 164). MEASUREMENTS AND MAIN RESULTS: Primary outcome was the overall incidence of VAP based on quantitative culture of distal pulmonary samplings performed after each clinical suspicion. Other outcomes included incidence of early- and late-onset VAP, duration of mechanical ventilation, and hospital mortality. Microbiologically confirmed VAP occurred in 67 patients, 25 of 169 (14.8%) in the SSD group and 42 of 164 (25.6%) in the control group (P = 0.02), yielding a relative risk reduction of 42.2% (95% confidential interval, 10.4-63.1%). Using the Day 5 threshold, the beneficial effect of SSD in reducing VAP was observed in both early-onset VAP (2 of 169 [1.2%] patients undergoing SSD vs. 10 of 164 [6.1%] control patients; P = 0.02) and late-onset VAP (23 of 126 [18.6%] patients undergoing SSD vs. 32 of 97 [33.0%] control patients; P = 0.01). VAP was clinically suspected at least once in 51 of 169 (30.2%) patients undergoing SSD and 60 of 164 (36.6%) control patients (P = 0.25). No significant between-group differences were observed in duration of mechanical ventilation and hospital mortality. CONCLUSIONS: Subglottic secretion drainage during mechanical ventilation results in a significant reduction in VAP, including late-onset VAP. Clinical trial registered with www.clinicaltrials.gov (NCT00219661).