This study evaluates the addition of tobramycin inhalation treatment to standard intravenous therapy in the treatment of ventilator associated pneumonia.

Rationale: Approximately 9-27% of mechanically ventilated patients in the intensive care unit (ICU) develop ventilator-associated pneumonia (VAP). Patients in whom VAP develops have a higher mortality rate up to 50%, stay longer in the intensive care unit (ICU), and require more resources than those without the disease. Despite the availability of modern ICU care and modern antibiotics, the overall clinical cure rate after 72 hours of antibiotic treatment for VAP is only 40%. The cure rate for Pseudomonas aeruginosa is even lower. It is unclear why VAP cure rates are so low. The ATS guidelines recommend IV antibiotic treatment (IV AB), especially directed against gram-negative microorganisms. However, the relatively poor response rates seen with intravenous therapy of VAP and the emergence of MDR organisms makes new treatment options desirable. The ATS/IDSA VAP guidelines recommend that "adjunctive therapy with an inhaled aminoglycoside or polymyxin (colistin) for MDR Gram-negative pneumonia should be considered, especially in patients who are not improving". It is therefore necessary to investigate whether adjunctive therapy with inhalation Tobramycin could ameliorate prognosis. The recommendations by the Society of Infectious Diseases Pharmacists are similar.

Inclusion Criteria:

• Mechanical ventilation 48 hours or more
• New or progressive radiologic pulmonary infiltrate

Together with at least two of the following three criteria (< 24 h):

• temperature >38°C
• leukocytosis >12,000/mm3 or leucopenia <4,000/mm3
• purulent respiratory secretions

Exclusion Criteria:

• patients with allergy to tobramycin
• pregnancy
• expected to die within 72 hours after enrollment