Controversies in Ventilator-Associated Pneumonia

ABSTRACT

Ventilator-associated pneumonia (VAP) is the most frequent intensive care unit (ICU)-acquired infection among patients receiving mechanical ventilation. Consensus, however, on the most appropriate diagnostic strategy for patients clinically suspected of having developed VAP has yet to be reached. Concern about the inaccuracy of clinical approaches to VAP recognition and potential for excessive use of antibiotics in the ICU had led numerous investigators to postulate that quantitative cultures of specimens obtained with bronchoscopic or nonbronchoscopic techniques, such as bronchoalveolar lavage (BAL) and/or protected specimen brush (PSB), could improve identification of patients with true VAP and facilitate decisions whether to treat. Other than decision-analysis studies and one retrospective study, only five trials assessed the impact of such a quantitative bacteriological strategy on antibiotic use and outcome of patients suspected of VAP using a randomized scheme. In one study, the invasive management strategy was significantly associated with earlier attenuation of organ dysfunction and less antibiotic exposure, but the four other trials could not replicate these positive findings, including a large Canadian study that enrolled 740 patients. Because antibiotics were continued in most patients with negative BAL cultures in contradiction with the bacteriological algorithm, additional studies will be needed before concluding that a strategy based on the systematic collection of distal pulmonary secretions before introduction of new antibiotics and quantitative culture techniques is useless and cannot prevent the overuse of antimicrobial agents in the ICU.

KEYWORDS

Ventilator-associated pneumonia - diagnostic techniques - bronchoalveolar lavage - clinical outcome - antimicrobial stewardship

REFERENCES

• 1 American Thoracic Society . Guidelines for the management of adults with hospital-acquired, ventilator-associated, and healthcare-associated pneumonia.  Am J Respir Crit Care Med. 2005;  171 388-416
• 2 Chastre J, Fagon J Y. Ventilator-associated pneumonia.  Am J Respir Crit Care Med. 2002;  165 867-903
• 3 Meduri G U. Diagnosis and differential diagnosis of ventilator-associated pneumonia.  Clin Chest Med. 1995;  16 61-93
• 4 Bonten M J, Bergmans D C, Stobberingh E E et al.. Implementation of bronchoscopic techniques in the diagnosis of ventilator-associated pneumonia to reduce antibiotic use.  Am J Respir Crit Care Med. 1997;  156 1820-1824
• 5 Fagon J Y, Chastre J, Wolff M et al.. Invasive and noninvasive strategies for management of suspected ventilator-associated pneumonia: a randomized trial.  Ann Intern Med. 2000;  132 621-630
• 6 Rello J, Gallego M, Mariscal D, Soñora R, Valles J. The value of routine microbial investigation in ventilator-associated pneumonia.  Am J Respir Crit Care Med. 1997;  156 196-200
• 7 Fagon J Y, Chastre J, Hance A J, Domart Y, Trouillet J L, Gibert C. Evaluation of clinical judgment in the identification and treatment of nosocomial pneumonia in ventilated patients.  Chest. 1993;  103 547-553
• 8 Shorr A F, Sherner J H, Jackson W L, Kollef M H. Invasive approaches to the diagnosis of ventilator-associated pneumonia: a meta-analysis.  Crit Care Med. 2005;  33 46-53
• 9 Heyland D K, Cook D J, Marshall J Canadian Critical Care Trials Group et al. The clinical utility of invasive diagnostic techniques in the setting of ventilator-associated pneumonia.  Chest. 1999;  115 1076-1084
• 10 McGowan Jr J E. Antimicrobial resistance in hospital organisms and its relation to antibiotic use.  Rev Infect Dis. 1983;  5 1033-1048
• 11 Kollef M H, Fraser V J. Antibiotic resistance in the intensive care unit.  Ann Intern Med. 2001;  134 298-314
• 12 Dellit T H, Owens R C, McGowan Jr J E Infectious Diseases Society of America et al. Infectious Diseases Society of America and the Society for Healthcare Epidemiology of America guidelines for developing an institutional program to enhance antimicrobial stewardship.  Clin Infect Dis. 2007;  44 159-177
• 13 Murthy R. Implementation of strategies to control antimicrobial resistance.  Chest. 2001;  119(2, Suppl) 405S-411S
• 14 Paterson D L. The role of antimicrobial management programs in optimizing antibiotic prescribing within hospitals.  Clin Infect Dis. 2006;  42(Suppl 2) S90-S95
• 15 Goldmann D A, Weinstein R A, Wenzel R P et al.. Strategies to prevent and control the emergence and spread of antimicrobial-resistant microorganisms in hospitals: a challenge to hospital leadership.  JAMA. 1996;  275 234-240
• 16 Croce M A, Fabian T C, Shaw B et al.. Analysis of charges associated with diagnosis of nosocomial pneumonia: can routine bronchoscopy be justified?.  J Trauma. 1994;  37 721-727
• 17 Meduri G U, Mauldin G L, Wunderink R G et al.. Causes of fever and pulmonary densities in patients with clinical manifestations of ventilator-associated pneumonia.  Chest. 1994;  106 221-235
• 18 Liu Y C, Huang W K, Huang T S, Kunin C M. Inappropriate use of antibiotics and the risk for delayed admission and masked diagnosis of infectious diseases: a lesson from Taiwan.  Arch Intern Med. 2001;  161 2366-2370
• 19 Johanson Jr W G, Seidenfeld J J, Gomez P, de los Santos R, Coalson J J. Bacteriologic diagnosis of nosocomial pneumonia following prolonged mechanical ventilation.  Am Rev Respir Dis. 1988;  137 259-264
• 20 Souweine B, Mom T, Traore O et al.. Ventilator-associated sinusitis: microbiological results of sinus aspirates in patients on antibiotics.  Anesthesiology. 2000;  93 1255-1260
• 21 Montravers P, Fagon J Y, Chastre J et al.. Follow-up protected specimen brushes to assess treatment in nosocomial pneumonia.  Am Rev Respir Dis. 1993;  147 38-44
• 22 Prats E, Dorca J, Pujol M et al.. Effects of antibiotics on protected specimen brush sampling in ventilator-associated pneumonia.  Eur Respir J. 2002;  19 944-951
• 23 Trouillet J L, Guiguet M, Gibert C et al.. Fiberoptic bronchoscopy in ventilated patients: evaluation of cardiopulmonary risk under midazolam sedation.  Chest. 1990;  97 927-933
• 24 Steinberg K P, Mitchell D R, Maunder R J, Milberg J A, Whitcomb M E, Hudson L D. Safety of bronchoalveolar lavage in patients with adult respiratory distress syndrome.  Am Rev Respir Dis. 1993;  148 556-561
• 25 Marquette C H, Herengt F, Mathieu D, Saulnier F, Courcol R, Ramon P. Diagnosis of pneumonia in mechanically ventilated patients: repeatability of the protected specimen brush.  Am Rev Respir Dis. 1993;  147 211-214
• 26 Gerbeaux P, Ledoray V, Boussuges A, Molenat F, Jean P, Sainty J M. Diagnosis of nosocomial pneumonia in mechanically ventilated patients: repeatability of the bronchoalveolar lavage.  Am J Respir Crit Care Med. 1998;  157 76-80
• 27 de Jaeger A, Litalien C, Lacroix J, Guertin M C, Infante-Rivard C. Protected specimen brush or bronchoalveolar lavage to diagnose bacterial nosocomial pneumonia in ventilated adults: a meta-analysis.  Crit Care Med. 1999;  27 2548-2560
• 28 Heyland D, Dodek P, Muscedere J, Day A. Canadian Critical Care Trials Group . A randomized trial of diagnostic techniques for ventilator-associated pneumonia.  N Engl J Med. 2006;  355 2619-2630
• 29 Meduri G U, Chastre J. The standardization of bronchoscopic techniques for ventilator-associated pneumonia.  Chest. 1992;  102(5, Suppl 1) 557S-564S
• 30 Rouby J J. Histology and microbiology of ventilator-associated pneumonias.  Semin Respir Infect. 1996;  11 54-61
• 31 Alvarez-Lerma F. ICU-Acquired Pneumonia Study Group . Modification of empiric antibiotic treatment in patients with pneumonia acquired in the intensive care unit.  Intensive Care Med. 1996;  22 387-394
• 32 Iregui M, Ward S, Sherman G, Fraser V J, Kollef M H. Clinical importance of delays in the initiation of appropriate antibiotic treatment for ventilator-associated pneumonia.  Chest. 2002;  122 262-268
• 33 Torres A, Ewig S. Diagnosing ventilator-associated pneumonia.  N Engl J Med. 2004;  350 433-435
• 34 Niederman M S. Bronchoscopy for ventilator-associated pneumonia: show me the money (outcome benefit)! [editorial; comment].  Crit Care Med. 1998;  26 198-199
• 35 Kirtland S H, Corley D E, Winterbauer R H et al.. The diagnosis of ventilator-associated pneumonia: a comparison of histologic, microbiologic, and clinical criteria.  Chest. 1997;  112 445-457
• 36 Cook D, Mandell L. Endotracheal aspiration in the diagnosis of ventilator-associated pneumonia.  Chest. 2000;  117(4, Suppl 2) 195S-197S
• 37 Singh N, Rogers P, Atwood C W, Wagener M M, Yu V L. Short-course empiric antibiotic therapy for patients with pulmonary infiltrates in the intensive care unit: a proposed solution for indiscriminate antibiotic prescription.  Am J Respir Crit Care Med. 2000;  162(2 Pt 1) 505-511
• 38 Ibrahim E H, Ward S, Sherman G, Schaiff R, Fraser V J, Kollef M H. Experience with a clinical guideline for the treatment of ventilator-associated pneumonia.  Crit Care Med. 2001;  29 1109-1115
• 39 Baker A M, Bowton D L, Haponik E F. Decision making in nosocomial pneumonia: an analytic approach to the interpretation of quantitative bronchoscopic cultures.  Chest. 1995;  107 85-95
• 40 Sterling T R, Ho E J, Brehm W T, Kirkpatrick M B. Diagnosis and treatment of ventilator-associated pneumonia—impact on survival: a decision analysis.  Chest. 1996;  110 1025-1034
• 41 Babcock H M, Zack J E, Garrison T, Trovillion E, Kollef M H, Fraser V J. Ventilator-associated pneumonia in a multi-hospital system: differences in microbiology by location.  Infect Control Hosp Epidemiol. 2003;  24 853-858
• 42 Sanchez-Nieto J M, Torres A, Garcia-Cordoba F et al.. Impact of invasive and noninvasive quantitative culture sampling on outcome of ventilator-associated pneumonia: a pilot study.  , [Erratum in: Am J Respir Crit Care Med 1998 Mar;157(3 Pt 1):1005] Am J Respir Crit Care Med. 1998;  157 371-376
• 43 Ruiz M, Torres A, Ewig S et al.. Noninvasive versus invasive microbial investigation in ventilator-associated pneumonia: evaluation of outcome.  Am J Respir Crit Care Med. 2000;  162 119-125
• 44 Solé Violán J, Fernández J A, Benítez A B, Cardeñosa Cendrero J A, Rodríguez de Castro F. Impact of quantitative invasive diagnostic techniques in the management and outcome of mechanically ventilated patients with suspected pneumonia.  Crit Care Med. 2000;  28 2737-2741
• 45 Croce M A, Fabian T C, Waddle-Smith L et al.. Utility of Gram's stain and efficacy of quantitative cultures for posttraumatic pneumonia: a prospective study.  Ann Surg. 1998;  227 743-751 discussion 751-755