Ventilator-associated pneumonia (VAP) is the second most frequent health care-acquired infection and contributes to significant morbidity and mortality. Studies have shown the cost of VAP to be equal to or exceed $40,000 per patient.1 Both good hand washing with soap and hot water and the use of alcohol-based antiseptics are vital to decontaminating the hands once there has been exposure to respiratory secretions. Bacteria that contribute to VAP also can colonize in places such as the artificial airway, ventilator circuit, and oral cavity, however. Good hand decontamination practice is not enough to protect the patient against bacterial growth in these mediums. Efforts from the Institute for Healthcare Improvement (IHI) to improve VAP outcomes have led to the initiation of ventilator bundles.2 In addition, the CDC has recommendations on the use of noninvasive ventilation and several recommendations on ventilator circuit care.
The use of passive versus active humidification and the effects each method has on VAP reduction have been studied with few significant findings.3 The goals of St Elizabeth/St Luke Hospitals’ approaches were to perform an extensive review of the literature and combine that with the most up-to-date clinical practice guidelines to develop an informed strategy to reduce VAP. The claim here is not that any single component of the strategies used in our approach had a direct impact on the outcomes, but that there is a potential correlation between the results and the sum of the strategies implemented. This was not intended to be a study, merely a campaign to put together a collection of the best evidence-based practices in an effort to improve patient safety and outcome.
Multidisciplinary Ventilator Bundle Program
Many hospitals have implemented bundle programs with mixed results. In knowing this, St Luke Hospitals wanted to take a team approach to achieve the highest level of success. The thought was that if everyone had ownership in the project, there would be greater collaboration and buy-in. Since this was going to be a team approach, it was important to provide the necessary education to nurses and respiratory therapists on all shifts. As part of a multidisciplinary task force, intensive care worked collaboratively with the ICU nurses and the respiratory therapy department toward the implementation of a ventilator bundle that included all components outlined by CDC recommendations and IHI as part of their 100,000 Lives Campaign. Both ICU nurses and respiratory therapy staff received 1-hour VAP education with training and rationales in the form of a video. A protocol checksheet was devised to show that each evidence-based practice component was being completed (Figure 1). Our bundle protocol comprised six components: head of bed (HOB) >30 degrees, daily sedation vacations, assessment of readiness to extubate, peptic ulcer disease (PUD) prophylaxis, deep vein thrombosis (DVT) prophylaxis, and Q4 oral care. The oral care kits and laminated protocols were affixed to the ICU wall for easy access for staff. Hands-on education of both staff teams occurred 1 week prior to the start of the study period and 1 month following the study. This education emphasized hand hygiene, adherence to aseptic technique, and oral cavity assessments. Compliance (Figure 2) was measured using the daily protocol checksheet per intubated patient and walking rounds by IC nurse managers and respiratory managers.
Some challenges to any hospital undertaking VAP bundle protocols:
- staff competency with equipment, knowledge of policies, and understanding the rationale behind bundle components;
- maintaining staff compliance over time;
- incorporating evidence-based practices into multidisciplinary teams;
- reinforcing education to seasoned staff while indoctrinating new hires;
- maintaining compliance as a department increases bed capacity;
- acquiring and utilizing vendor support to enhance staff education;
- availability of dedicated funding for educational tools.
Changes in Ventilator Circuit Management
In addition to the ventilator bundle, there were some other initiatives put into place that followed current literature and recommendations by the CDC. The CDC recommends that ventilator circuits should be monitored regularly so that accumulated condensate in the tubing can be removed.4 Even when traditional circuitry is closely monitored, it is difficult to keep condensation from accumulating. In theory, heat and moisture exchangers (HMEs) can reduce incidence of VAP by reducing condensate within a vent circuit.5 The combined results of a meta-analysis of six studies found in the AARC’s evidence-based guideline on ventilator circuit care concluded that there was a statistically lower VAP rate with the use of passive humidification, but when the studies were looked at individually, only one reported a significant reduction in VAP.6 Additionally, HMEs can provide insufficient heat and humidification and are not recommended for use beyond 96 hours.7 HMEs require the therapist or nurse to remove them from the circuit when administering medication or to replace them when they are clogged with mucus. Breaking the circuit only increases the likelihood of introducing microorganisms that can cause pneumonia. What if the clinician forgets to remove the HME? How much of the medicine will the patient actually receive? While there are HMEs on the market that allow the therapist to turn a dial so that medication can be delivered without removing the HME, how many times does a therapist forget to turn the dial back, causing the patient to receive no humidification at all? To eliminate these risks, we decided to implement the use of active humidification using heated-wire circuits on all of our ICU patients. This resulted in little circuit condensation, and, with the use of spring-loaded valves and aerosol tees, there was limited need to break the circuit when administering medication.
Increasing the Use of Noninvasive Ventilation
For years, traditional intubation with positive pressure ventilation has been the primary practice when treating patients in respiratory distress who are spiraling downward toward failure. The use of invasive positive pressure ventilation (IPPV) can be life-saving, but it also can lead to numerous complications. In addition to causing complications such as damage to the upper airway and a potential for VAP,7 IPPV with an endotracheal tube diminishes patients’ ability to communicate effectively and hampers their ability to eat. Noninvasive positive pressure ventilation (NPPV) is a CDC category level II recommendation when medically indicated.4 The push to increase the use of NPPV for patients suffering from acute respiratory failure due to COPD exacerbation and pulmonary edema was not a road easily traveled. Our respiratory therapists understood the principles and theory behind its use for these patients but became easily frustrated with the time spent—only to end up intubating in the end. While there is no evidence that supports that the use of NPPV reduces mortality rates over IPPV, a summary of randomized controlled trials showed that in three out of eight studies, there was a significant reduction in the intubation rate.8 If the number of patients being intubated declines, then it is a fair assumption that the rate of VAP in those patients should decline as a result. It was not until about 3 years ago—when new technology made possible devices that provided the flow characteristics, adequate oxygen delivery, and leak compensation necessary to support the patient’s needs—that we started having greater success with keeping patients on NPPV for longer periods of time and preventing intubation. In addition, there has been a vast improvement with full-face mask technology that provides better comfort, leading to improved patient compliance. Unfortunately, the data on patients placed on NPPV and intubation rates were not tracked so there are no results to report. What can be reported when comparing the same quarter of 2007 to 2008 is the increase in the usage of NPPV and a decrease in the usage of IPPV (Figures 3).
While this is only a short time during which to compare data, it is a reflection of the overall trend in our hospitals. There is no argument here for a direct correlation between the increase in the use of NPPV and a reduction in our VAP rate. This data is only to report the success of our efforts to follow the CDC’s recommendations to reduce VAP. Appropriate use of NPPV is arguably more an art than any other respiratory therapy given today. It takes countless hours to perfect the patient/device response in order to achieve the desired effect, and as any therapist or nurse who has had much experience with NPPV will tell you, it is often much easier to sedate and intubate a critically ill patient. As any clinician in our organization who has experience with NPPV will tell you, however, the results are worth the frustration.
In fiscal year 2007, our two facilities annually admitted 19,740 patients, respectively. Comparing a period from January through April 2007 and 2008, average NPPV/day had increased from 3.85 to 7.2 (P = 0.00084), while invasive vents/day had decreased from 6.62 to 4.9 (P = 0.035). Patient admissions during that same period increased from 5,829 in 2007 to 5,896 in 2008, more than 3 years have passed since the VAP program was implemented, and this hospital has maintained a “0” VAP rate per 6,902 ventilator days through April 2008 using NNIS criteria to determine VAP.
Little is known about the incidence and precursors of VAP in trauma patients. From discussions with colleagues and investigators on this topic around the United States, it has become clear to me that many institutions have difficulty in VAP reduction in this patient population. Certainly, the lack of upper airway protective mechanisms among trauma patients is a strong contributing factor for a higher incidence of VAP. It is important to note that St Luke Hospitals do not treat trauma patients, and this could have been a contributing factor to the zero VAP rate reported here. Implementation of a comprehensive program that includes a VAP bundle, use of NPPV, and good ventilator circuit management may reduce VAP rates. The participation of both nursing and respiratory care teams in these initiatives builds a productive collaboration between the two disciplines. Regularly scheduled education and daily checks increase staff compliance and successful outcomes.
Travis Collins, RRT, is director of Pulmonary Services, St Elizabeth/St Luke Hospitals, Fort Thomas, Ky. Ginny Lipke, RN, MHA, ACRN, is Infection Control Preventionist (CTR/TSI), HIV/TB Prevention and Care, Global AIDS Program, Centers for Disease Control and Prevention, Atlanta. For further information, contact [email protected]
- Rello J, Ollendorf DA, Oster G, et al. Epidemiology and outcomes of ventilator-associated pneumonia in a large U.S. database. Chest. 2002;22:2115-21.
- Institute for Healthcare Improvement. Implementing the ventilator bundle. Available at: www.ihi.org/IHI/Topics/CriticalCare/IntensiveCare/Changes/ImplementtheVentilatorBundle.htm. Accessed March 30, 2009.
- Hess DR, Kallstrom TJ, Mottram CD, et al. Care of the ventilator circuit and its relation to ventilator-associated pneumonia. Respir Care. 2003;48:869-79.
- Tablan OC, Anderson LJ, Besser R, Bridges C, Hajjeh R. Guidelines for preventing health-care-associated pneumonia. Hospital Infection Control Practices Advisory Committee. MMWR. March 26, 2004;53(RR03):1-36.
- Craven DE, Goularte TA, Make BJ. Contaminated condensate in mechanical ventilator circuits: a risk factor for nosocomial pneumonia? Am Rev Respir Dis. 1984;129:625-8.
- Kirton OC, DeHaven B, Morgan J, Morgan O, Civetta J. A prospective randomized comparison of an in-line heat moisture exchanger filter and heated wire humidifiers: rates of ventilator-associated early-onset (community-aquired) or late-onset (hospital-acquired) pneumonia and incidence of endotracheal tube occlusion. Chest. 1997;112:1055-9.
- AARC Clinical Practice Guideline. Humidification during mechanical ventilation. Respir Care. 1992;37:887-90.
- Mehta S, Al-Hassim AH, Kennan SP. Noninvasive ventilation in patients with acute cardiogenic pulmonary edema. Respir Care. 2009;54:186-97.