New Study Shows Subglottic Secretions Drainage Reduces VAP and Antibiotic Use

BOULDER, Colo. – A two-year randomized study just published in the peer-reviewed journal Chest (November 2008) demonstrates that continuous aspiration of subglottic secretions (CASS) significantly reduced antibiotic usage in post-cardiac surgery patients.  CASS was also found to reduce the incidence of ventilator-associated pneumonia (VAP), ICU length of stay, and duration of mechanical ventilation in patients intubated for more than 48 hours. 

The study, which enrolled 714 patients, was conducted by a team led by Emilio Bouza, MD, PhD, of the GregorioMarañónUniversityGeneralHospital in Madrid, Spain. Cardiac surgery patients were randomized to receive either a standard endotracheal tube or the Hi-Lo Evac™ tube to facilitate CASS, also known as subglottic secretions drainage (SSD). Other VAP interventions, such as head of bed elevation and stress-ulcer prophylaxis, were standardized in both groups throughout the duration of the study. 

Although subglottic secretions drainage has previously been shown in several studies to reduce VAP, this new study is believed to be the first that has also clearly shown reductions in ICU length of stay and antibiotic usage with the use of CASS.  

“In this era of growing concern about antibiotic resistance and the high cost of antibiotics, preventing VAP is clearly preferable to treating it,” said Roger Mecca, MD, vice president of medical affairs for Covidien, manufacturer of the Hi-Lo Evac™ endotracheal tube used in the study. “This is one of the first independent studies in the literature that demonstrates not only a reduction in VAP in patients intubated more than 48 hours, but a reduction in antibiotic requirements and duration of mechanical ventilation attributable to the use of CASS,” said Mecca.

Key findings of the study include the following:

• Inpatients who were mechanically ventilated more than 48 hours, the use of CASS reduced the incidence of VAP by 43 percent.

• Inpatients who were mechanically ventilated more than 48 hours, the use of CASS was associated with 9.5 fewer ICU days and four fewer days of mechanical ventilation.

• In all patients and in those patients who were mechanically ventilated more than 48 hours, CASS was associated with a very significant reduction in the use of antibiotics.

VAP is associated with up to a 27 percent attributable mortality rate and more than $40,000 average increase in hospital cost per incidence. Dialogue about "never events,” public reporting of VAP rates, and possible changes in reimbursement by the Centers for Medicare & Medicaid Services (CMS) have brought increased focus on VAP prevention among care providers and hospital administrators.

“Covidien strongly supports the use of a CASS protocol in patients requiring mechanical ventilation,” Mecca said.  “CASS protocols are recommended in leading infection control guidelines including those from the Centers for Disease Control, the American Thoracic Society, and the Infectious Diseases Society of America.”  


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