RESUMEN

La neumonía asociada a ventilador (NAV), es una entidad clínica con elevada prevalencia en las Unidades de Cuidados Intensivos (UCI). De las infecciones nosocomiales es la que tiene mayor mortalidad; su incidencia aumenta de manera exponencial con cada día de ventilación mecánica (VM). Entre otros factores de riesgo además de la VM están la alcalinidad gástrica, mal manejo de material de inhaloterapia, uso indiscriminado de antibióticos, y la multiplicidad de procedimientos invasivos. La identificación de la enfermedad es por una alta sospecha clínica que se reafirma con la placa simple de tórax, en la cual el mejor hallazgo son nuevos infiltrados con broncograma aéreo, sumado a hallazgos de laboratorio con leucocitosis o leucopenia. Las técnicas para obtención de muestras para identificar el germen causal son muy variadas; sin embargo las técnicas broncoscópicas juegan un papel preponderante, siendo las más sensibles y específicas el lavado broncoalveolar (LBA) y el espécimen con cepillo protegido (ECP). El tratamiento con antibióticos se debe iniciar al identificarse el cuadro de acuerdo a la severidad, tiempo de aparición, y, sobre todo de acuerdo con la flora prevalente; no obstante, puede retrasarse hasta 6 horas en aquellos pacientes sin choque séptico en lo que se obtienen muestras para cultivos.

PALABRAS CLAVE

Neumonía asociada a ventilador, epidemiología, gérmenes causales, métodos de obtención de muestras, tratamiento.

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