Original Contributions
An emergency department–based randomized trial of nonbronchoscopic bronchoalveolar lavage for early pathogen identification in severe community-acquired pneumonia*,**,

https://doi.org/10.1067/mem.2001.118014Get rights and content

Abstract

Study Objectives: Many patients with community-acquired pneumonia are treated empirically without an aggressive search for causative pathogens, an approach adopted largely because of the costs and difficulties encountered during efforts to identify the causative organisms. Blood and sputum cultures are not sensitive, and the more invasive techniques of broncoscopy and lung biopsy are generally time consuming and not cost-effective. The technique of nonbronchoscopic bronchoalveolar lavage (BAL) has been shown to accurately diagnose the causes of nosocomial pneumonia. The purpose of this study was to determine whether an emergency department–based BAL protocol would lead to more frequent isolation of pneumonia pathogens and result in more changes to tailored antibiotic therapy in comparison with standard care. Methods: We studied all adult patients admitted with a diagnosis of pneumonia who were tracheally intubated and who had obtainable familial consent in the ED of an urban county hospital from March 1998 to October 1999. Exclusions included antibiotic use within the past 5 days, pneumothorax, hemoptysis, or persistent hypoxia using 100% oxygen. Patients were randomized to standard care versus standard care plus BAL. Blood culture specimens were drawn from all patients before the initiation of antibiotics. All other diagnostic tests were ordered at the discretion of treating physicians. BAL fluid, sputum, and blood culture specimens were tracked, and patient antibiotic course was followed to assess any change in regimen. Results: Twenty-six of 64 patients evaluated for study participation met all eligibility criteria; 14 patients received standard care, and 12 patients received standard care plus BAL. Pneumonia pathogens were identified in 10 (83.3%) of 12 patients in the BAL group and in 4 (28.6%) of 14 patients in the standard care group (P =.007). Comparing BAL versus non-BAL groups, there was no significant difference in the likelihood of overall antibiotic regimen changes (P =.149), but there was a difference with regard to antibiotic changes made in patients with positive culture test results (P =.026). No major complications occurred with BAL catheterizations. Conclusion: ED–based BAL catheterization allows for early identification of pathogens in severe community-acquired pneumonia, which leads to changes in antibiotic therapy. [Rodriguez RM, Fancher ML, Phelps M, Hawkins K, Johnson J, Stacks K, Rossini T, Way M, Holland D. An emergency department–based randomized trial of nonbronchoscopic bronchoalveolar lavage for early pathogen identification in severe community-acquired pneumonia. Ann Emerg Med. October 2001;38:357-363.]

Introduction

Pneumonia is the leading cause of infectious disease–related mortality in the United States,1 resulting in approximately 500,000 hospitalizations and 45,000 deaths annually.2 With regard to diagnostic strategies for community-acquired pneumonia (CAP), the basic infectious disease principle that the identification of underlying pathogens leads to more specific and effective treatment plans is generally not supported.3 American Thoracic Society guidelines recommend presumptive therapy without an aggressive search for the underlying pathogens.4 Guidelines endorsed by the Infectious Disease Society of America have diverged from this approach in recent years, recommending sputum culture, Gram stain, and pretreatment blood culture testing for patients requiring hospitalization.2 However, routine blood and sputum cultures are insensitive tests for severe CAP (SCAP) pathogen identification.5, 6, 7, 8, 9, 10, 11, 12 Furthermore, sputum cultures may provide misleading information when contaminated with upper airway flora.2, 13 Because of these difficulties encountered during standard efforts to isolate true pathogens for SCAP, treatment for pneumonia is still largely empiric and based on the most likely causes according to patient age, underlying illness, clinical history, and radiographic appearance. Compared with noninvasive modalities, the more invasive techniques of bronchoscopy with protected brushing and lung biopsy provide far more accurate and reliable information about the causes of pneumonia,14, 15, 16, 17, 18, 19 but they have generally not been found to be cost-effective compared with the empiric therapy approach. Furthermore, these invasive techniques are generally performed by specialist physicians and may be difficult to arrange on a consistent and widespread basis in most hospitals.

Bronchoalveolar lavage (BAL) catheterization has been shown to be an inexpensive, safe, and effective alternative to traditional bronchoscopic techniques in the diagnosis of ventilator-associated pneumonia (VAP).20, 21, 22, 23, 24 BAL catheterization can be performed at the bedside by respiratory therapists or nonpulmonary physicians, in contrast to traditional bronchoscopy, which generally requires dedicated facilities and the involvement of a pulmonologist. With a thin, directional (right lung versus left lung), telescoping inner cannula analogous to a protected brush, BAL catheterization provides for relatively simple lavage and sampling of the lower airways in tracheally intubated patients. Additionally, the BAL catheter diameter is much smaller than that of a standard bronchoscope, allowing for easier ventilation during the procedure.

The purpose of this study was to determine whether the institution of a protocol with early emergency department–based BAL catheterization would lead to improved diagnostically useful information in the treatment of tracheally intubated patients with SCAP. Specifically, we hypothesized that in patients randomized to standard care plus BAL catheterization, we would more commonly identify the causative organisms of pneumonia when compared with patients randomized to standard care alone. Additionally, we hypothesized that this increased yield of organisms would more often lead to changes in antibiotic therapy, especially changes to tailored therapy for specific isolated pathogens. Finally, we proposed that this technique could be enacted in the ED setting without significant complications and without delaying the delivery of first-dose antibiotics.

Section snippets

Materials and methods

The study protocol was approved by the hospital's institutional review board committee. This study was conducted from March 1998 through October 1999 in the ED of an urban county hospital (annual census, approximately 125,000). During this time period, we evaluated all adult patients who were admitted with a diagnosis of SCAP, were ventilated with an endotracheal tube or a tracheostomy, and had consent obtainable from a family member or other surrogate. Exclusion criteria were any antibiotic

Results

Of the 64 patients initially evaluated for study participation, 26 met all eligibility criteria. Fourteen patients were excluded because of antibiotic therapy within the past 5 days, 14 were too hypoxic or died too rapidly for study participation, and consent was unobtainable in 10 patients. Of the 26 patients enrolled in the study, 14 patients were randomized to receive standard care, and 12 patients were randomized to the standard care plus BAL catheterization group (see Figure for flow

Discussion

In this prospective randomized trial, pathogens causing SCAP were identified in a significantly higher percentage of patients who received standard care plus BAL catheterization compared with patients who received standard care alone. Although we noted no significant difference between the 2 groups in overall changes in antibiotic regimens, we did observe significantly more antibiotic regimen changes in the BAL group when a positive culture was obtained. The BAL catheterization procedure was

Acknowledgements

Author contributions: All authors contributed to the design and implementation of the study. RMR and MP were the primary writers of the manuscript, while the other authors reviewed the manuscript and made suggestions for its revision. RMR takes overall responsibility for the paper.

References (45)

  • A Ortqvist et al.

    Diagnostic fiberoptic bronchoscopy and protected brush culture in patients with community-acquired pneumonia

    Chest

    (1990)
  • SL. Murphy

    Deaths: Final data for 1998. National Vital Statistics Reports. Hyattsville, MD: Centers for Disease Control and Prevention

  • JG Bartlett et al.

    Guidelines from the Infectious Diseases Society of America. Practice guidelines for the management of community-acquired pneumonia in adults

    Clin Infect Dis

    (2000)
  • MS Niederman et al.

    Guidelines for the initial management of adults with community-acquired pneumonia: diagnosis, assessment of severity, and initial antimicrobial therapy. American Thoracic Society

    Am Rev Respir Dis

    (1993)
  • MJ Fine et al.

    Evaluation of house staff physicians' preparation and interpretation of sputum Gram's stains for community-acquired pneumonia

    J Gen Intern Med

    (1991)
  • PM DeBlieux et al.

    Community-acquired pneumonia: deciding whom to admit and which antibiotics to use

    Emerg Med Pract.

    (1999)
  • DJ. Flournoy et al.

    Interpreting the sputum Gram's stain report

    Lab Med

    (1998)
  • A Torres et al.

    Severe community-acquired pneumonia: epidemiology and prognostic factors

    Am Rev Respir Dis

    (1991)
  • AJ Kirby et al.

    Thrush and fever as measures of immunocompetence in HIV-infected patients

    AIDS

    (1998)
  • BJ Marston et al.

    Incidence of community-acquired pneumonia requiring hospitalization

    Arch Intern Med

    (1997)
  • LB Reller et al.

    Diagnostic microbiology updates

    Clin Infect Dis

    (1998)
  • Cited by (0)

    *

    Author contributions are provided at the end of this article.

    **

    Catheters for this study were supplied by Ballard Medical Products, Inc., Draper, UT.

    Address for reprints: Robert M. Rodriguez, MD, Alameda County Medical Center, Highland Hospital Campus, Department of Emergency Medicine, 1411 East 31st Street, Oakland, CA 94602; 510-437-8394, fax 510-308-3959; E-mail,[email protected]

    View full text