Document Type : Review articles


Department of Surgery/Anesthesia, College of Medicine, University of Anbar, Ramadi, Anbar, Iraq


The difficulty of early diagnosis, the proper anti-microbial chosen, and the relatively high morbidity and mortality; make us collect the related subjects to deal with the most critical complication (ventilator-associated pneumonia) showing the major points needed for every intensivist. Ventilator-associated pneumonia is considered the most common respiratory complication (infection) in intensive care unit patients. Ventilator-associated pneumonia can be defined as a hospital-acquired infection of the lung parenchyma that occurs after 2 days of mechanical ventilation. Its incidence is about 9-25% in intubated patients for more than 2 days. We could classify ventilator-associated pneumonia as early and late; the first one happened within four days of receiving mechanical ventilation, otherwise, the late onset occurred after day four. Some patients with hospital stays before intensive care unit admission and intubation are considered to have late ventilator-associated pneumonia regardless of the period of mechanical ventilation because those patients might have had pathogens previously (nosocomial). Severe ill patients, prolonged mechanical ventilation, and failed extubation trials (recurrent intubation) lead to the development of ventilator-associated pneumonia rapidly and aggressively. Furthermore,ventilator-associated pneumonia is attributed to prolonged hospitality as well as high morbidity and mortality. We aimed in this narrative review to discuss ventilator-associated pneumonia regarding the etiology, causative agents, risk factors, strategies for early diagnosis, accurate treatment, and optimal prevention protocols.


Main Subjects

[1]      M.-Y. Wang, L. Pan, and X.-J. Hu, “Chest physiotherapy for the prevention of ventilator-associated pneumonia: A meta-analysis,” Am. J. Infect. Control, vol. 47, no. 7, pp. 755–760, 2019.
[2]      J. E. Bennett, “Principles and practice of infectious diseases.” Elsevier, 2020.
[3]      L. Papazian, M. Klompas, and C.-E. Luyt, “Ventilator-associated pneumonia in adults: a narrative review,” Intensive Care Med., vol. 46, no. 5, pp. 888–906, 2020.
[4]      F. H. R. De Winter et al., “Mechanical ventilation impairs IL-17 cytokine family expression in ventilator-associated pneumonia,” Int. J. Mol. Sci., vol. 20, no. 20, p. 5072, 2019.
[5]      N. Vargas-Cruz et al., “Nitroglycerin-citrate-ethanol catheter lock solution is highly effective for in vitro eradication of Candida auris biofilm,” Antimicrob. Agents Chemother., vol. 63, no. 7, pp. e00299-19, 2019.
[6]      M. L. Metersky and A. C. Kalil, “Management of ventilator-associated pneumonia: guidelines,” Clin. Chest Med., vol. 39, no. 4, pp. 797–808, 2018.
[7]      Y. WU, Y. YIN, P. GAO, and Y. CHEN, “Effects of not monitoring gastric residual volume on the risk of ventilator-associated pneumonia: a meta-analysis,” Chinese J. Pract. Nurs., pp. 2555–2561, 2020.
[8]      J.-L. Vincent et al., “The prevalence of nosocomial infection in intensive care units in Europe: results of the European Prevalence of Infection in Intensive Care (EPIC) Study,” Jama, vol. 274, no. 8, pp. 639–644, 1995.
[9]      S. Chevret, M. Hemmer, J. Carlet, and M. Langer, “Incidence and risk factors of pneumonia acquired in intensive care units,” Intensive Care Med., vol. 19, no. 5, pp. 256–264, 1993.
[10]    A. S. Cross and B. Roup, “Role of respiratory assistance devices in endemic nosocomial pneumonia,” Am. J. Med., vol. 70, no. 3, pp. 681–685, 1981.
[11]    P. Esnault et al., “Early-onset ventilator-associated pneumonia in patients with severe traumatic brain injury: incidence, risk factors, and consequences in cerebral oxygenation and outcome,” Neurocrit. Care, vol. 27, no. 2, pp. 187–198, 2017.
[12]    W. Beachey, Respiratory Care Anatomy and Physiology E-Book: Foundations for Clinical Practice. Elsevier Health Sciences, 2022.
[13]    F. Gao et al., “The effect of reintubation on ventilator-associated pneumonia and mortality among mechanically ventilated patients with intubation: a systematic review and meta-analysis,” Hear. Lung, vol. 45, no. 4, pp. 363–371, 2016.
[14]    T. E. Meawed, S. M. Ahmed, S. M. S. Mowafy, G. M. Samir, and R. H. Anis, “Bacterial and fungal ventilator associated pneumonia in critically ill COVID-19 patients during the second wave,” J. Infect. Public Health, vol. 14, no. 10, pp. 1375–1380, 2021.
[15]    T. F. Huzar and J. M. Cross, “Ventilator-associated pneumonia in burn patients: a cause or consequence of critical illness?,” Expert Rev. Respir. Med., vol. 5, no. 5, pp. 663–673, 2011.
[16]    D. R. Park, “The microbiology of ventilator-associated pneumonia,” Respir. Care, vol. 50, no. 6, pp. 742–765, 2005.
[17]    Y. Erfani, A. Rasti, and L. Janani, “Prevalence of Gram-negative bacteria in ventilator-associated pneumonia in neonatal intensive care units: a systematic review and meta-analysis protocol,” BMJ Open, vol. 6, no. 10, p. e012298, 2016.
[18]    S. Golia, K. T. Sangeetha, and C. L. Vasudha, “Microbial profile of early and late onset ventilator associated pneumonia in the intensive care unit of a tertiary care hospital in Bangalore, India,” J. Clin. diagnostic Res. JCDR, vol. 7, no. 11, p. 2462, 2013.
[19]    R. Sharma, T. E. Park, and S. Moy, “Ceftazidime-avibactam: a novel cephalosporin/β-lactamase inhibitor combination for the treatment of resistant gram-negative organisms,” Clin. Ther., vol. 38, no. 3, pp. 431–444, 2016.
[20]    J. Chastre et al., “Nosocomial pneumonia in patients with acute respiratory distress syndrome,” Am. J. Respir. Crit. Care Med., vol. 157, no. 4, pp. 1165–1172, 1998.
[21]    N. M. Joseph, S. Sistla, T. K. Dutta, A. S. Badhe, and S. C. Parija, “Ventilator-associated pneumonia: a review,” Eur. J. Intern. Med., vol. 21, no. 5, pp. 360–368, 2010.
[22]    P. MARKOWICZ et al., “Multicenter prospective study of ventilator-associated pneumonia during acute respiratory distress syndrome: incidence, prognosis, and risk factors,” Am. J. Respir. Crit. Care Med., vol. 161, no. 6, pp. 1942–1948, 2000.
[23]    J. Rello, V. Ausino, M. Ricart, J. Castella, and G. Prats, “Impact of previous antimicrobial therapy on the etiology and outcome of ventilator-associated pneumonia,” Chest, vol. 104, no. 4, pp. 1230–1235, 1993.
[24]    J. Rello et al., “Survival in patients with nosocomial pneumonia: impact of the severity of illness and the etiologic agent,” Crit. Care Med., vol. 25, no. 11, pp. 1862–1867, 1997.
[25]    J. Rello, M. Gallego, D. Mariscal, R. Sonora, and J. Valles, “The value of routine microbial investigation in ventilator-associated pneumonia,” Am. J. Respir. Crit. Care Med., vol. 156, no. 1, pp. 196–200, 1997.
[26]    L. Lorente, S. Blot, and J. Rello, “New issues and controversies in the prevention of ventilator-associated pneumonia,” Am. J. Respir. Crit. Care Med., vol. 182, no. 7, pp. 870–876, 2010.
[27]    C. for D. C. and Prevention, “Guidelines for prevention of nosocomial pneumonia,” Morb Mortal Wkly Rep, vol. 46, pp. 1–79, 1997.
[28]    J. Chastre et al., “Comparison of 8 vs 15 days of antibiotic therapy for ventilator-associated pneumonia in adults: a randomized trial,” Jama, vol. 290, no. 19, pp. 2588–2598, 2003.
[29]    A. F. Shorr, Y. P. Tabak, V. Gupta, R. S. Johannes, L. Z. Liu, and M. H. Kollef, “Morbidity and cost burden of methicillin-resistant Staphylococcus aureus in early onset ventilator-associated pneumonia,” Crit. Care, vol. 10, no. 3, pp. 1–7, 2006.
[30]    P. E. Grgurich, J. Hudcova, Y. Lei, A. Sarwar, and D. E. Craven, “Management and prevention of ventilator-associated pneumonia caused by multidrug-resistant pathogens,” Expert Rev. Respir. Med., vol. 6, no. 5, pp. 533–555, 2012.
[31]    J. D. Hunter, “Ventilator associated pneumonia,” Bmj, vol. 344, 2012.
[32]    E. M. Brown, “Empirical antimicrobial therapy of mechanically ventilated patients with nosocomial pneumonia.,” J. Antimicrob. Chemother., vol. 40, no. 4, pp. 463–468, 1997.
[33]    C. H. Marquette et al., “Diagnostic tests for pneumonia in ventilated patients: prospective evaluation of diagnostic accuracy using histology as a diagnostic gold standard.,” Am. J. Respir. Crit. Care Med., vol. 151, no. 6, pp. 1878–1888, 1995.
[34]    S. H. Kirtland et al., “The diagnosis of ventilator-associated pneumonia: a comparison of histologic, microbiologic, and clinical criteria,” Chest, vol. 112, no. 2, pp. 445–457, 1997.
[35]    M. Langer, M. Cigada, M. Mandelli, P. Mosconi, and G. Tognoni, “Early onset pneumonia: a multicenter study in intensive care units,” Intensive Care Med., vol. 13, no. 5, pp. 342–346, 1987.
[36]    J. P. Metlay et al., “Diagnosis and treatment of adults with community-acquired pneumonia. An official clinical practice guideline of the American Thoracic Society and Infectious Diseases Society of America,” Am. J. Respir. Crit. Care Med., vol. 200, no. 7, pp. e45–e67, 2019.
[37]    T. C. Horan et al., “Nosocomial infections in surgical patients in the United States, January 1986-June 1992,” Infect. Control Hosp. Epidemiol., vol. 14, no. 2, pp. 73–80, 1993.
[38]    J.-Y. Fagon, J. Chastre, A. J. Hance, P. Montravers, A. Novara, and C. Gibert, “Nosocomial pneumonia in ventilated patients: a cohort study evaluating attributable mortality and hospital stay,” Am. J. Med., vol. 94, no. 3, pp. 281–288, 1993.
[39]    L. Papazian et al., “Effect of ventilator-associated pneumonia on mortality and morbidity.,” Am. J. Respir. Crit. Care Med., vol. 154, no. 1, pp. 91–97, 1996.
[40]    W. G. Melsen, M. M. Rovers, and M. J. M. Bonten, “Ventilator-associated pneumonia and mortality: a systematic review of observational studies,” Crit. Care Med., vol. 37, no. 10, pp. 2709–2718, 2009.
[41]    A. A. Kalanuria, M. Mirski, and W. Ziai, “Ventilator-associated pneumonia in the ICU,” Annu. Updat. Intensive Care Emerg. Med. 2014, pp. 65–77, 2014.
[42]    J.-M. Forel et al., “Ventilator-associated pneumonia and ICU mortality in severe ARDS patients ventilated according to a lung-protective strategy,” Crit. Care, vol. 16, no. 2, pp. 1–10, 2012.
[43]    A. Stoclin et al., “Ventilator-associated pneumonia and bloodstream infections in intensive care unit cancer patients: a retrospective 12-year study on 3388 prospectively monitored patients,” Support. Care Cancer, vol. 28, no. 1, pp. 193–200, 2020.
[44]    Y. Li, C. Liu, W. Xiao, T. Song, and S. Wang, “Incidence, risk factors, and outcomes of ventilator-associated pneumonia in traumatic brain injury: a meta-analysis,” Neurocrit. Care, vol. 32, no. 1, pp. 272–285, 2020.
[45]    W. G. Melsen, M. M. Rovers, M. Koeman, and M. J. M. Bonten, “Estimating the attributable mortality of ventilator-associated pneumonia from randomized prevention studies,” Crit. Care Med., vol. 39, no. 12, pp. 2736–2742, 2011.