Implementing three autonomous nursing interventions together helps avert the processes known to cause VAP.

Reducing hospital-acquired pneumonia continues to pose a challenge for healthcare providers. Among critically ill patients in acute-care facilities, pneumonia is one of the most common hospital-acquired infections. The American Thoracic Society defines ventilator-associated pneumonia (VAP) as a hospital-acquired lung infection in patients who’ve been on a mechanical ventilator for at least 48 hours. (See CDC criteria for clinically defining VAP).

Patients receiving mechanical ventilation are more likely to develop hospital-acquired infections than those who aren’t. The artificial airway of the ventilator or the endotracheal (ET) tube can transmit microorganisms to the lungs. VAP in critically ill patients is an adverse outcome and a national patient-safety concern. It increases ventilator days, patient morbidity and mortality, and healthcare costs.

Two processes are crucial to VAP development:

• bacterial colonization of the oral cavity
• aspiration of contaminated secretions into the lower respiratory tract.

The literature includes extensive discussion of VAP diagnosis and treatment, along with interventions attributed to reducing its incidence. This article describes a “bundle” of autonomous nursing interventions that can help prevent both of the etiologic processes above and improve patient outcomes.

Gap between evidence and practice

Several reports from the Institute of Medicine (IOM) have raised awareness of medical errors and inconsistent care delivery. These reports have contributed to implementation of national patient-safety initiatives and heightened the demand for standardizing quality of care in hospitals. In 2001, IOM identified six national safety aims for improving health care: providing safe, effective, patient-centered, timely, efficient, and equitable care. Healthcare teams and researchers have implemented and tested various interventions geared to improving patient safety and reducing untoward outcomes.

Selected interventions or care processes have been shown to decrease mortality, morbidity, and healthcare costs in mechanically ventilated patients. These interventions include evidence-based practice guidelines from the Centers for Disease Control and Prevention (CDC) pertaining to VAP prevention, as well as guidelines on hand hygiene, staff education, semirecumbent positioning, oral care and decontamination with antibiotic rinses, early extubation, weaning protocols, aspiration of subglottic secretions, and use of closed-suction catheter systems and silver-coated ET tubes.

But despite the documented findings, gaps exist between awareness of the evidence and implementation of evidenced-based guidelines into daily nursing practice. Also, a basic concept must be considered when implementing patient-safety or risk-reduction interventions to solve healthcare challenges: matching interventions to the cause of the problem. Focusing on both of the processes known to cause VAP enables healthcare providers to implement effective patient risk-reduction activities.

Nursing interventions to prevent VAP

Over the past 10 years, literature on nursing interventions for reducing VAP has focused on elevating the head of the patient’s bed and providing mouth care. During the past 2 years, researchers have explored the importance of maintaining optimal ET-tube cuff pressure.

This article focuses on three key interventions that address both known causes of VAP:

• maintaining ET-tube cuff pressure
• keeping the head of the bed elevated
• providing mouth care.

Although many studies have shown that head-of-bed elevation and mouth care help prevent VAP, these interventions are implemented inconsistently. The American Association of Critical Care Nurses (AACN) has established two evidenced-based practice alerts pertaining to VAP reduction; one addresses head-of-bed elevation and the other addresses oral care. Clinical practices associated with maintaining optimal ET tube cuff pressure vary, largely from lack of knowledge of the benefit of this intervention.

Maintaining ET tube cuff pressure

The cuff at the lower end of the ET tube is used to seal the airway during mechanical ventilation and minimize aspiration into the lower respiratory tract. A routine part of airway care is to measure and monitor ET tube cuff pressure to assess for a tracheal seal. Cuff pressure should be maintained above 20 cm H2O to minimize the aspiration risk, but below the tracheal mucosal capillary perfusion pressure of 25 to 30 cm H2O to minimize tracheal erosion.

Elevating the head of the bed

Elevating the head of the bed is a well-documented way to help reduce VAP. Maintaining an angle of 30 to 45 degrees at all times reduces the aspiration risk, whereas supine positioning has been shown to increase risk. AACN’s VAP practice alert recommends an elevation of 30 to 45 degrees (unless medically contraindicated) for all patients receiving mechanical ventilation or who are at a high risk for aspiration (for instance, those with an enteral tube and a decreased level of consciousness).

Providing mouth care

Colonization of dental plaque from organisms in the oral cavity has been linked to hospital-acquired infections and VAP in mechanically ventilated patients. Providing mouth care decolonizes the oral cavity. AACN’s practice alert recommends providing mouth care every 2 to 4 hours. According to this alert, critical-care and acute-care settings should develop and implement a comprehensive oral hygiene program. The latter should include protocols for brushing the patient’s teeth, gums, and tongue and moisturizing the oral mucosa and lips.

Bundling interventions to improve care quality

The Institute of Healthcare Improvement (IHI) defines bundling of interventions as the “grouping of best practices with respect to a disease process that individually improve care, but when applied together result in substantially greater improvement.” The ventilator bundle recognized by IHI and the Joint Commission consists of a group of evidence-based practices that, when implemented together, dramatically reduce VAP incidence in mechanically ventilated patients. The bundle includes these interventions:

• head-of-bed elevation above 30 degrees
• peptic-ulcer disease (stress ulcer) prophylaxis
• deep-vein thrombosis prophylaxis
• appropriate sedation use (“sedation vacation”).

The IHI ventilator bundle is included in current national policies and quality-improvement initiatives aimed at improving ventilator care. Hospitals across the country are implementing it and collecting and reporting data on its key interventions.

Although the bundle has been documented to decrease mortality and minimize the aspiration risk, it lacks an intervention to decolonize the oral cavity. Thus, an opportunity exists to improve healthcare quality and redefine strategies for VAP prevention.

Opportunities to reduce VAP

We know little about how the bundling of autonomous nurse-initiated interventions affects VAP incidence. An autonomous nursing intervention is one that nurses can implement independently, based on their education and knowledge. To date, literature on the three autonomous nursing interventions discussed in this article have been explored individually to reduce VAP.

The author’s dissertation study found that the optimal bundle for reducing VAP includes these three interventions:

• maintaining ET tube cuff pressure between 20 and 25 cm H2O
• keeping the head of the bed elevated 30 to 45 degrees
• providing mouth care every 2 or every 4 hours.

The study found that the risk of developing VAP fell 97.6% and the expected time until VAP occurred was almost 3.5 times longer in patients who’d received the optimal intervention bundle than in those who hadn’t. Implementing an autonomous nursing-intervention bundle that minimizes both the risk of aspiration into the lower respiratory tract and oral-cavity colonization reduced VAP incidence by 55.4%. Bundling the three interventions achieved better patient outcomes than if these same interventions had been implemented individually. (See Nursing-intervention bundle to reduce VAP By clicking on PDF icon above.)

Recommendations

The autonomous nursing-intervention bundle described above interrupted transmission of microorganisms to the lower respiratory tract. This bundle matches interventions with the two processes known to cause VAP. Bundling the interventions significantly contributed to reducing VAP in critically ill patients, indicating that applying consistent interventions can reduce risk and improve patient outcomes.

The concept of matching interventions to the cause of a specific problem can be generalized to address other healthcare challenges. Once interventions are matched to the cause of the problem, nursing interventions can be bundled and evidence can be incorporated into nursing practice and policy.

Selected references

American Association of Critical Care Nursing. Practice alert: Oral care in the critically ill. ww.aacn.org/WD/Practice/Docs/Oral_Care_in_the_Critically_Ill.pdf. Accessed January 20, 2011.

American Association of Critical Care Nursing. Practice alert: Ventilator associated pneumonia. www.aacn.org/WD/Practice/Docs/Ventilator_Associated_Pneumonia_1-2008.pdf. Accessed January 20, 2011.

American Thoracic Society. Guidelines for the management of adults with hospital-acquired, ventilator-associated, and healthcare-associated pneumonia. Am J Respir Crit Care Med. 2005;171(4):388-416.

Association for Professionals in Infection Control and Epidemiology (APIC). An APIC Guide: Guide to the Elimination of Ventilator-Associated Pneumonia. Washington, DC: APIC; 2009.

Centers for Disease Control and Prevention. Ventilator-associated pneumonia (VAP) event. www.cdc.gov/nhsn/PDFs/pscManual/6pscVAPcurrent.pdf. Accessed January 20, 2010.

Curtin L. Nursing strategies in reducing ventilator-associated pneumonia: Program evaluation. Dissertation Abstracts International; 2007.

Green LR, Sposato K. Guide to the Elimination of Ventilator-Associated Nneumonia. Washington, DC: Association for Professionals in Infection Control and Epidemiology; 2009.

Institute for Healthcare Improvement. Implement the ventilator bundle. http://www.ihi.org/resources/Pages/Tools/HowtoGuidePreventVAP.aspx. Accessed January 20, 2011.

Institute of Medicine. Crossing the Quality Chasm: A New Health System for the 21st Century. Washington, DC: National Academy Press; 2001.

Institute of Medicine. To Err Is Human: Building a Safer Health System. Washington, DC: National Academy Press; 2000.

Lyerla F, LeRouge C, Cooke DA, Turpin D, Wilson L. A nursing clinical decision support system and potential predictors of head-of-bed position for patients receiving mechanical ventilation. Am J Crit Care. 2010;19(1):39-47.

Murray T, Goodyear-Bruch C. Ventilator-associated pneumonia improvement program. AACN Adv Crit Care. 2007;18(2):190-199.

Sole ML, Aragon D, Bennett M, Johnson RL. Continuous measurement of endotracheal tube cuff pressure: how difficult can it be? AACN Adv Crit Care. 2008;19(2):235-243.

Tablan OC, Anderson LJ, Besser R, Bridges C, Hajjeh R. Guidelines for preventing health-care-associated pneumonia, 2003: Recommendations of CDC and the Healthcare Infection Control Practices Advisory Committee. www.cdc.gov/ncidod/dhqp/pdf/guidelines/CDCpneumo_guidelines.pdf. Accessed January 20, 2011.

Tablan OC, Anderson LJ, Besser R, Bridges C, Hajjeh R. March 26, 2004. Guidelines for preventing health-care-associated pneumonia, 2003. MMWR. 53(RR-03):1-36.

Linda J. Curtin is the director of Nursing Education and Research at Good Samaritan Medical Center in Brockton, Massachusetts.