Managing Suspected Ventilator-Associated Pneumonia FREE

Patients connected to mechanical ventilators (“breathing machines”) sometimes develop lung infection. This is known as ventilator-associated pneumonia. Ventilator-associated pneumonia is hard to diagnose because patients on ventilators can develop the usual clinical findings of pneumonia (x-ray changes, fever, bronchial secretions, and bacteria in the respiratory tract) for many reasons other than pneumonia. Treating patients with antibiotics when they do not really have ventilator-associated pneumonia subjects them to the potential side effects and expense of the drugs. Some experts have recommended using invasive tests to diagnose ventilator-associated pneumonia rather than relying on clinical findings. The invasive tests involve inserting an instrument called a bronchoscope into the patient's respiratory tract to obtain samples of lung fluid and tissue. This potentially risky and expensive procedure has never been proven to improve patient outcomes.

To find out whether a strategy that involves invasive tests to diagnose ventilator-associated pneumonia is better than a strategy that relies on clinical findings.

From 31 intensive care units in France, the researchers studied 413 patients suspected of having ventilator-associated pneumonia.

The researchers randomly assigned patients to the use of either invasive diagnostic tests or clinical findings to guide the diagnosis and treatment of suspected ventilator-associated pneumonia. They then followed these patients to see who died or developed complications involving the heart, kidneys, lungs, nervous system, liver, or blood clotting. They also measured antibiotic use at 14 and 28 days.

After accounting for baseline differences in the groups, patients who underwent the invasive tests were less likely than those in the clinical findings group to have died or suffered organ failure at 14 days. The advantage of using the invasive approach was less clear at 28 days, but the patients who had invasive tests still did better. The invasive strategy patients also had more antibiotic-free days than the clinical findings group.

In this study, the doctors were aware of which group the patients were in, which could have influenced the way they prescribed antibiotics. In addition, the tests used to look for bacteria in lung fluids (cultures) in this study may differ from the ones used at other hospitals.

This study suggests that patients who undergo invasive tests to diagnose and manage suspected ventilator-associated pneumonia do better and spend fewer days taking antibiotics than patients in whom diagnosis and management is guided only by clinical findings.