[Nosocomial ventilator-associated pneumonia in a tropical intensive care unit]

Nosocomial ventilator-associated pneumonia (VAP) occupy an important place among nosocomial infections and are responsible for a very high mortality. The objective of this work was to study epidemiologic, diagnostic and therapeutic aspects of ventilator-associated pneumonia in a tropical Intensive Care Unit and to release an adapted strategy of antimicrobial treatment.

It is a prospective descriptive study carried out from January to December 2002 in the polyvalent intensive care unit, in collaboration with the laboratory of bacteriology-virology of the CHU Dantec of Dakar. We included all the patients admitted and who presented radiological pulmonary infiltrates appearing after 48 hours of mechanical ventilation, associated to at least 2 clinic or biologic criteria and to a positive tracheal aspirate with a cut off value of 10(4) CFU/ml.

Thirty two cases of VAP have been diagnosed among 446 patients admitted in our ICU. The incidence was 7.16 per 100 admitted patients and 50 per 100 ventilated patients. The reasons for ICU admission were dominated by trauma (44%). Microorganisms responsible of VAP were essentially Gram negative bacilli (GNB), 68% with in head the Pseudomonas. Acinetobacter strains were practically resistant to all usually used antibiotics. The more used antibiotics were gentamicine, 3rd generation cephalosporins and fluoroquinolones. Antibiotic treatment was appropriate in only 13 cases in 26 patients at whom intrinsic antibacterial activities of antimicrobial agents were examined. The mortality rate was of 81%.

The improvement of the prognosis of these VAP require preventive measures with protocols of care, a qualified staff, diagnostic means and active antibiotics on the responsible pathogens.