ResultsA total of 528 cases of P. aeruginosa infection in the ICUs were enrolled in the 6-year study. The prevalence of CRPA and MDRPA (multidrug-resistance P. aeruginosa) was 18.4 and 25.6%, respectively. Significant risk factors related to CRPA infection were the length of hospitalization >28 days (OR = 3.241, 95% CI 1.622–6.473, p = 0.001), receiving invasive operations (OR = 2.393, 95% CI 1.196–4.788, p = 0.014) and a blood transfusion (OR = 7.003, 95% CI 2.416–20.297, p < 0.001) within 30 days before infection. Conversely, birth weight ≥2,500 g (OR = 0.278, 95% CI 0.122–0.635, p = 0.001) and breast nursing (OR = 0.362, 95% CI 0.168–0.777, p = 0.009) were significant protective factors against CRPA infections. The in-hospital mortality rate was 14.2%, and no difference in mortality was observed between patients with CRPA and CSPA infections. Platelet < 100 × 109/L (OR = 5.729, 95% CI 1.048–31.308, p = 0.044) and serum urea <3.2 mmol/L (OR = 5.173, 95% CI 1.215–22.023, p = 0.026) were independent predictors for the mortality due to P. aeruginosa infection.