Study objective: To determine the cost-effectiveness of
continuous subglottic suctioning (CSS) as a strategy to decrease the
incidence of ventilator-associated pneumonia (VAP).
Design: Decision-model analysis of the cost and efficacy of
endotracheal tubes that allow CSS at preventing VAP. The primary
outcome was cases of VAP averted. Model estimates were based on data
from published prospective trials of CSS and other prospective studies
of the incidence of VAP. Setting and
patients: Hypothetical cohort of 100 patients requiring
nonelective endotracheal intubation and management in an ICU.
Interventions: In the model, patients were managed with
either traditional endotracheal tubes (ETs) or ETs capable of CSS.
Measurements and main results: The marginal
cost-effectiveness of CSS was calculated as the savings resulting from
cases of VAP averted minus the additional costs of CSS-ETs, and
expressed as cost (or savings) per episode of VAP prevented.
Sensitivity analysis of the impact of the major clinical inputs on the
cost-effectiveness was performed. The base case assumed that the
incidence of VAP in patients requiring > 72 h of mechanical
ventilation (MV) was 25%, that CSS-ETs had no impact on patients
requiring MV for < 72 h, and that CSS-ETs resulted in a relative risk
reduction of VAP of 30%. Despite the higher costs of ETs capable of
CSS, this tactic yielded a net savings of $4,992 per case of VAP
prevented. For sensitivity analysis, model inputs were adjusted by 50%
individually and then simultaneously. This demonstrated the model to be
only moderately sensitive to the calculated cost of VAP. With the
relative risk reduction at 50% of the base-case estimate, CSS resulted
in $1,924 saved per case of VAP prevented. When all variables were
skewed against CSS, total outlays were trivial (approximately $14 per
patient in the cohort).
Conclusions: CSS represents a
strategy for the prevention of VAP that may result in savings. Further
studies are warranted to confirm the efficacy of