Epidemiology of ventilator-associated tracheobronchitis and ventilator-associated pneumonia caused by multidrug-resistant Gram-negative bacteria at a tertiary care hospital in Thailand

Abstract

Objectives: To investigate the epidemiology of MDR Gram-negative bacilli ventilator-associated tracheobronchitis (MDR GNB-VAT) and MDR GNB ventilator-associated pneumonia (MDR GNB-VAP) among mechanically ventilated patients.

Methods: We conducted a retrospective observational study among hospitalized patients who underwent continuous mechanical ventilation for ≥48 h at Siriraj Hospital, Thailand.

Results: During the 18 month study period, 1824 unique patients underwent continuous mechanical ventilation (12 216 ventilator-days). The cumulative incidences of MDR GNB-VAT and -VAP were 8.4% and 8.3%, respectively. The incidence rates of MDR GNB-VAT and -VAP were 12.52 and 12.44 episodes/1000 ventilator-days, respectively. Among those with VAT, the cumulative incidence and incidence rate of subsequent VAP development within 7 days were 11.76% and 2.81 episodes/1000 ventilator-days, respectively. The median durations of mechanical ventilation before having VAP and VAT were 9 and 12 days, respectively. Multivariate analysis identified three independently associated factors for patients having VAP compared with having VAT: underlying cerebrovascular disease [adjusted OR (aOR): 0.46; 95% CI: 0.27-0.78; P = 0.04], previous surgery (aOR: 0.68; 95% CI: 0.57-0.8; P < 0.001) and acute renal failure (aOR: 1.75; 95% CI: 1.27-2.40; P = 0.001).

Conclusions: The study revealed high incidences of MDR GNB-VAT and -VAP among mechanically ventilated patients. The independent risk factors for having VAP can help identify patients at risk for developing VAP and who need early weaning from mechanical ventilation.

Figure 1.

Study flowchart.