The Utility of an Enhanced Bundle and Chlorhexidine Mouthwash in Reducing Ventilator-Associated Pneumonia

Background: Ventilator-associated pneumonia (VAP) contributes to the morbidity and mortality as well as the cost of caring for critically ill patients.  A performance improvement project was initiated to implement a care bundle for ventilated patients to decrease the risk in this high risk population.

Objective: To evaluate the efficacy of an enhanced care bundle to prevent ventilator associated pneumonia.

Methods: A VAP bundle was implemented in our surgical ICU in July 2007 and monitored through June 2009 (study period).  The bundle included head of bed (HOB) elevation, sedation holiday, stress ulcer prophylaxis, subglottic suctioning, periodic patient turning, deep vein thrombosis (DVT) prophylaxis, and an enhanced hand hygiene program for house staff and visitors.  Initially, daily oral hygiene was performed using a bicarbonate formulation; this was changed to chlorhexidine (CHG) in July 2008.  Bundle adherence and compliance were tracked.  VAP case definition was based on CDC surveillance criteria.  VAP incidence densities (#cases/ventilator-days x 1000) were compared by calculating incidence rate ratios (IRR).

Results: Of 6,050 patients admitted to the ICU and mechanically ventilated during the study period, 64 (1.1%) met the case definition.  The mean age was 51.5 years; male-to-female ratio was 43:21.  The VAP incidence density fell from 26.8 in July 2007 to 3.1 in January 2008 (IRR=0.3, p <0.0001).  The mean monthly VAP incidence density for the period February through September 2008 was 5.2; we then documented a further gradual fall in the incidence density over the next eight months to 1.8 in June 2009 (IRR=0.5, p <0.05).  Adherence to the bundle components after the first and second year were, respectively, as follows: HOB, 92.5% and 93.6%; sedation holiday, 59.3% and 66.7%; stress ulcer prophylaxis, 98.6% and 95.2%; oral care, 90.9% and 93.8%; subglottic suctioning, 89.5% and 96.7%; turning of patients, 92.8% and 95%; and DVT prophylaxis 99.8% and 96.4%. 
The annual cost of VAP in 2007 ($40,000 per VAP x 180) was $7,200,000, decreased to $1,640,000 in 2008 and is projected to fall to $600,000 in 2009.  The overall savings was $5,560,000 in 2008 and $1,040,000 for an estimated overall savings of $6,596,000. Additionally, the average length of stay fell from 4.78 in January 2007 to 4.11 in June 2009.

Conclusions: A significant decrease in VAP rates and attributable costs was achieved over a two-year period following implementation of an enhanced VAP bundle.  Moreover, once implemented, the compliance with the VAP bundle components did not vary significantly over this period.  A further significant decrement in the VAP rate was documented following the introduction of CHG oral care.  In conclusion, the adoption of an enhanced ventilator bundle is paramount for the reduction of VAP rates, and further decreases in these rates may be expected when CHG oral care is included in the bundle.