1995 OPEN FORUM Abstracts
A PROSPECTIVE, RANDOMIZED TRIAL OF 7 DAY VENTILATOR CIRCUIT CHANGES VERSUS NO ROUTINE CIRCUIT CHANGES FOR PATIENTS REQUIRING PROLONGED MECHANICAL VENTILATION.
Patricia Silver, RRT, ME, Linda Hossin, RRT, Rodger Richards, CRTT, Mona Hearns, CRTT, Steven Shapiro, M.D., Victoria Fraser, M.D., Marin Kollef, M.D. Pulmonary and Critical Care Division, Washington University School of Medicine, and The Departments of Respiratory Therapy and Infection Control, Barnes Hospital and Jewish Hospital, St. Louis, MO.
Introduction: Preliminary studies performed to date suggest that ventilator circuit changes can be safely extended beyond 48 hours without increasing the risk of ventilator-associated pneumonia (VAP). However, the maximum safe duration between breathing circuit changes is currently unknown as suggested by the Centers for Disease Control and Prevention (Infect Control Hosp Epidemiol 1994; 15:587). Therefore, we performed a two center study to determine if a practice of not routinely changing ventilator circuits in patients requiring prolonged mechanical ventilation (> 5 days) is associated with an increased incidence of nosocomial pneumonia.
Methods: Prospective, randomized trial comparing seven day breathing circuit changes to no circuit changes with the main outcome measure being the occurrence of VAP. Breathing circuits were only changed in the group randomized to no circuit changes if they appeared soiled.
Results: (following a scheduled review of the data at 6 months).
7 day circuit change No circuit change P value
(n = 120) (n = 128)
Age, yr: 58.9±19.7 61.8±17.2 0.23
APACHE II score:18.4±7.920.3±8.50.06
Organ Failure Score: 1.9±0.7 2.2±0.8 0.09
PaO_2/FiO_2: 242±125 232±126 0.53
Circuit changes:1.4±1.9 0.07±0.3 ɘ.001
Hospital LOS, d:31.9±23.3 29.9±18.2 0.45
Duration of MV, d: 14.7±12.0 15.2±12.7 0.77
VAP:28 (23.3%)31 (24.2%) 0.87
ventilator days)15.8 15.9NS
(APACHE = Acute Physiology and Chronic Health Evaluation; LOS = Length of Stay; MV = mechanical ventilation; VAP = ventilator-associated pneumonia.)
Conclusions: These interim results suggest that the occurrence of VAP is not significantly increased in patients requiring prolonged mechanical ventilation who receive no routine breathing circuit changes.