Fig 1.
Flow diagram for VAP definition.
Firstly, a deterioration in ventilation following a period of stability defined according to positive end expiratory pressure (PEEP): ≥ 2 days of stable or decreasing daily minimum PEEP followed by a rise in daily minimum PEEP of ≥ 2.5 cm H2O, sustained ≥ 2 calendar days; or FiO2: ≥2 days of stable or decreasing daily minimum fraction of inspired oxygen(FiO2) followed by a rise in daily minimum FiO2 ≥ 0.15 points, sustained ≥ 2 calendar days. Secondly, systemic signs of fever >38°C or <36°C or white blood cell count >12×109/L or <4×10 9/L were required. Final criteria was an increased/new purulent tracheal aspirate (TA) samples/tracheobronchial secretions or ≥25 neutrophils per low power field (10 objective) on Gram stain of tracheal aspirate and either new and persistent infiltrates, consolidation, or cavitation as read by two study physicians on chest X-ray, or the decision to commence new antibiotic therapy.
Fig 2.
Flow diagram of the study enrollment procedure and categorization into five categories.
Patients enrolled in the study were into five groups depending upon intubation, pneumonia development, and VAP development: These were: I-P-V- (not intubated, no pneumonia), I-P+V- (not intubated, but pneumonia developed), I+P-V- (intubated but no pneumonia), I+P+V-(intubated and pneumonia developed, but VAP not confirmed), and I+P+V+(VAP confirmed). The flow diagram of the study enrollment procedure and categorization into five categories is shown in “Fig 2”.
Table 1.
Baseline characteristics of patients enrolled in the study.
Table 2.
Kruskal-wallis rank sum test for the variables associated with intubation and pneumonia.
Table 3.
Kruskal-Wallis rank sum test for the variables associated with different categories.
Fig 3.
Pairwise Wilcoxon signed rank test performed among the five defined categories to identify significance between the groups.
I = intubated, P = pneumonia, V = VAP. P-value from pairwise wilcox-test with bonferroni correction.
Fig 4.
Etiology of VAP and non-VAP specimen.
Table 4.
Etiology of VAP and non-VAP specimens.
Fig 5.
MDR isolates in VAP and non-VAP specimen.