Ventilator Associated Pneumonia Critical Care Clinics Mortality and ventilator dependence in critically ill patients with ventilator associated pneumonia caused by carbapenem resistant Acinetobacter baumannii ScienceDirect Researching the Changes of Serum Procalcitonin Levels in Ventilat Frequency, Etiology, Mortality, Cost, and Prevention of Respiratory Tract InfectionsProspective, One Center Study IDR Dove Medical Press Impact of ventilator associated pneumonia on mortality and epidemiological features of patients with secondary peritonitis Annals of Intensive Care Springer Nature Link