The Value of Routine Microbial Investigation in Ventilator-Associated Pneumonia

Abstract

The use of microbiologic investigations in routine clinical practice, their value in guiding antibiotic prescription, and their influence on outcome were prospectively studied in 113 consecutive adults who developed ventilator-associated pneumonia (VAP). Blood cultures were performed in 78.7% of cases, protected specimen brushing in 95.5%, and bronchoalveolar lavage in only 45.1%. No causative agent was identified in 13 episodes (11.5%), and results of microbial tests directed a change in therapy in 43 (38.0%). Bronchoscopic results revealed inadequate initial selection of antibiotic therapy in 27 cases (23.9%) and led to a change in antibiotic treatment. Inadequate initial selection was still associated with a significantly greater increase in related mortality than adequate initial therapy (37.0% versus 15.4%, p < 0.05), although the change in therapy permitted clinical resolution in 17 (62.9%) of these 27 episodes, and 10 patients were discharged alive. Bronchoscopic results also permitted the reduction of the antibiotic spectrum in seven episodes (6.1%). This study suggests that in patients with VAP, bronchoscopic results are frequently associated with changes in antibiotic therapy. Nevertheless, our findings also emphasize the critical importance of an appropriate early antibiotic therapy.

Ventilator-Associated Pneumonia in a Multi-Hospital System Differences in Microbiology by Location

“…The organisms associated with ventilator-associated pneumonia that we identified are similar to those reported in the literature. 12,13,15,16,18 The most common causes overall are P. aeruginosa and Staphylococcus aureus. Early cases of ventilator-associated pneumonia are more commonly associated with methicillin-sensitive Staphylococcus aureus and late cases with methicillin-resistant Staphylococcus aureus.…”

“…Inadequate antibiotic therapy has been associated with increased mortality from ventilator-associated pneumonia in several studies. 7,[9][10][11][12][13][14] Risk factors for receiving inadequate antimicrobial therapy include prior antibiotic exposure, presence of invasive devices, prolonged hospital stay, and prolonged ventilatory support. 14 Several studies have recommended that antibiotic choices be guided by knowledge of the common etiologic agents for ventilator-associated pneumonia in individual hospitals.…”

“…14 Several studies have recommended that antibiotic choices be guided by knowledge of the common etiologic agents for ventilator-associated pneumonia in individual hospitals. [13][14][15][16] There may be significant differences in the microbiologic etiologies of pneumonia in different hospitals and in different intensive care units (ICUs) within a single hospital. Little data exist about ventilator-associated pneumonia in pediatric settings.…”

Microbial investigation in ventilator-associated pneumonia

“…Several studies have shown that an inadequate antibiotic treatment is related to a poor prognosis [3,13]. The isolation of the causative organism and the investigation of the susceptibility to antibiotics may allow a more appropriate and adjusted treatment with potential bene®ts for the patient as well as for the antibiotic policy of the hospital.…”

Estudo bacteriológico do lavado broncoalveolar na gestão de antibióticos na pneumonia associada à ventilação mecânica de pacientes em unidades de terapia intensiva cirúrgica

“…Além de dificuldades diagnósticas, a causa é outro desafio. Métodos quantitativos e qualitativos têm sido testados [4][5][6] . Entre vários métodos de cultura, a quantitativa por lavado broncoalveolar (LBA) é a mais utilizada.…”