Fighting ventilator-associated pneumonia

Douglas Hansell looks at tools and strategies for minimizing the risk of VAP and other pulmonary complications.

“For the medical community there are significant opportunities to advance the prevention of VAP and post-intubation pulmonary complications”
-Douglas Hansell

Could you please discuss ventilator-associated pneumonia and explain how patients contract it?
Douglas Hansell. We know that the risk for infection increases the longer a patient is mechanically ventilated. There are probably several mechanisms, but certainly a primary one has to do with microaspiration or leakage of secretions around the tracheal tube cuff.

With increasing time on the ventilator and time in the ICU, a patient's secretions become colonized and the ability to precipitate pneumonia from microaspiration is a real phenomenon. Standard tracheal tube cuff technology hasn't changed in nearly 40 years. Our new product, the TaperGuard™ Evac tube, uses a different design that substantially reduces the risk of microaspiration.

VAP is also part of a much broader problem with a very large impact on the healthcare system: post-intubation or post-operative pulmonary complications, sometimes called PIPC. Post-intubation pulmonary complications are surprisingly common and are associated with significant mortality. As with VAP, microaspiration may be the primary cause of or may further exacerbate a wide range of these complications.

What strategies can hospitals use to help prevent patients from contracting VAP?
DH. The problem needs to be attacked with a multitude of strategies, from oral care and oral hygiene to keeping the head of the bed elevated, to managing sedation in the ICU and striving for earlier ventilator weaning and earlier removal of the endotracheal tube.

One of the strategies that has also been highly productive has to do with removing secretions from above the endotracheal cuff.  Subglottic secretions drainage with the Mallinckrodt™ Evac tube has been shown to reduce VAP by up to 75 percent. When we look at the data, combining subglottic secretions drainage with the new cuff may be even more effective in reducing leakage past the cuff.

In summary, attacking the problem is multimodal, and many different techniques and procedural changes in technology have been applied to the problem. The latest technology that can advance this is the TaperGuard™ Evac tube.

Whatis the TaperGuard™ tube and how does it reduce the risk of microaspiration?
DH. The way most endotracheal cuffs are designed hasn't changed since the mid-1970s. Because they're designed to be larger than the trachea, they tend to form folds or micro-channels when they're inflated in the trachea. Those micro-channels allow fluid to move past the cuff and down into the lungs. Their ability to seal out fluid has marked limitations.

What's revolutionary with the TaperGuard™ tube cuff is that it's more taper-shaped, which allows the cuff diameter to match the diameter of the trachea at some point along the cuff. That reduces the micro-channels at the sealing zone, and markedly improves sealing characteristics. The TaperGuard™ cuff offers a 90 percent reduction in micro-aspiration compared to our Hi-Lo tube cuff.

What can be done to eliminate VAP and the broader problem of post-intubation pulmonary complications?
DH. I don't think we'll be able to eliminate post-intubation pulmonary complications entirely because they have multiple causes. They're dependent on the type of surgery, on pre-existing illness and on the state of the patient coming into surgery. It's a little like cardiac complications after surgery: we can't eliminate them, but we as an industry and as a medical community have focused heavily on cardiac complications over the past 10, 15, 20 years or even longer, and we've made a lot of headway there.

For the medical community there are significant opportunities to advance the prevention of VAP and post-intubation pulmonary complications. Can we eliminate them? No, but we have the ability with existing technologies and focus to change the game and make some major in-roads.

It's going to take multiple modalities to go after that, not just the TaperGuard™ tube, although it will obviously play a role. It will involve getting patients off the ventilator faster. It will involve technologies for monitoring patients for respiratory compromise even after they're extubated. We're looking at this space very broadly in terms of the different technologies and how we can make improvements.

Douglas M. Hansell, MD, MPH is Medical Director for Covidien. A Harvard-based physician, Dr. Hansell has over 20 years of multi-sector healthcare experience. In addition, Hansell has maintained an active clinical practice in Anesthesiology at Massachusetts General Hospital in Boston and has held teaching appointments at Harvard University. Hansell is board certified in Internal Medicine and Anesthesiology, fellowship trained in cardiovascular anesthesia and experienced in critical care medicine.