The Effect of Pravastatin on the Incidence and in the Natural Course of Ventilatory Associated Pneumonia in the Intensive Care Unit Patients

INTRODUCTION

The pneumonia in the intensive care unit (I.C.U.) constitutes the most frequent infection and is most often associated with the application of the mechanical ventilation. VAP (Ventilator - Associated Pneumonia) is defined as the nosocomial pneumonia in a patient on mechanical ventilatory support (by endotracheal tube or tracheostomy) for more than 48 hours. The risk for such complication is proportionally increased with the duration of hospitalization. The symptoms include the appearance of pulmonary infiltrate, fever, leukocytosis and purulent tracheobronchial secretions although this symptomatology is not always present. VAP is usually caused by several nosocomial species, such as Acinetobacter baumanni (the most often), Pseudomonas aeruginosa, Klebsiella pneumoniae.

VAP is frequently complicated with the entry of bacteria in the circulation of blood resulting in bacteremia and sepsis. In this respect, this disorder is associated with substantial morbidity and devastating costs of hospitalization. Notably, the cost of one episode of VAP is estimated in 57000 $ per occurrence.

On this basis, several strategies have been implicated to minimize the risk of VAP and to manage effectively the disease (5-12). Among these, antinflammatory treatment has been used in the past to influence the course of and to alter favorably the outcome of VAP (13).

Statins (HMG-CoA-reductase inhibitors), are drugs that regulates the speed of composition of cholesterol suspending the composition of cholesterol in very precocious stage. Recent studies have brought in the surface new attributes of statins. Statins present anti-inflammatory and immunomodulatory effects. They may modify the regulation of cytokines, (released from the cellular damage) and they may reduce the production of C-reactive protein levels (14-19). It has been hypothesized that these pleiotropic characteristic of statins might be useful in the management of various diseases (20), including pneumonia. Indeed, a recent study showed that statin treatment is associated with reduced risk of pneumonia in diabetic patients (18). However, the relationship between statins and reduced risk of pneumonia is not consistent (19). In addition there is no prospective study to investigate the role of statins in severe forms of pneumonia such as the VAP. We therefore contacted a double open label randomized trial to investigate whether the use of pravastatin reduces the incidence of Ventilator Associated Pneumonia in the ICU and whether it is related with favorable outcome of patients with Ventilator Associated Pneumonia.