SepsisImpact of bedside open lung biopsies on the management of mechanically ventilated immunocompromised patients with acute respiratory distress syndrome of unknown etiology
Introduction
Acute respiratory distress syndrome (ARDS) is a frequent cause of long duration of mechanical ventilation in critically ill patients [1]. Guidelines for the management of this syndrome include the identification of all possible causes susceptible to benefit from a specific treatment [2], [3]. Nevertheless, despite an extensive diagnostic process, including sophisticated imaging techniques (high-resolution computed tomodensitometry, nuclear magnetic resonance, positron emission tomography) and microbiology (cultures, serology-based and polymerase chain reaction–based detection of microorganisms in the blood or in specimens obtained through bronchoalveolar lavage [BAL]), the etiology of ARDS remains unknown in 5% to 10% of patients [4], [5].
In worsening ARDS of unidentified cause, many clinicians empirically combine broad spectrum antimicrobial agents with immunosuppressive therapy as steroids, and the impact of such potentially contradictory strategies may itself contribute to worsen the prognosis [6], [7]. In this situation, lung tissue histologic examination may be useful, particularly in immunocompromised patients as suggested from older series [8], [9]. Hence, surgical biopsy is a recognized accurate diagnostic method for diffuse lung disease in immunocompetent patients [10]. In patients with respiratory distress, many authors suggest that surgical open lung biopsies (OLBs) can be performed safely with a high diagnosis yield [11], [12], even if the they have hematologic diseases [13]. Papazian et al [14] reported in 1998 a very low rate of complications and suggested that such procedure may be performed at the bedside.
We reviewed specifically our local surgical OLBs performed at the bedside of patients with ARDS of unknown etiology after extensive diagnostic process and requiring mechanical ventilation for persistent respiratory failure despite aggressive empirical treatments. The scope was to evaluate whether that procedure had brought an impact on the management or treatment decision in these patients.
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Patients and methods
We identified retrospectively all patients hospitalized in the medical intensive care unit (ICU) of our institution with ARDS who underwent a bedside surgical OLB between 1993 and 2005. This unit is a tertiary and teaching hospital with 1500 beds, with an average of 1500 admissions every year for a median length of stay of 3 days. The ethical committee of the institution approved the extraction of data from the medical charts. Potential cases were identified through a review of the operative
Results
Of 54 patients who underwent a surgical lung biopsy in the institution, 19 open biopsies were performed in the medical ICU at the bedside for ARDS between 1993 and 2005. The 19 patients represented around 8% to 10% of all ARDS and their characteristics at the time of biopsy are summarized in Table 1. As described in Table 2, a majority (89%) of the patients were immunocompromised and many received long-term corticosteroids. Two patients were not immunosuppressed and developed an ARDS after
Discussion
Our data confirm that surgical OLB for ARDS of unknown etiology is safe and may provide important information susceptible to induce major changes in the management of these patients. This has already been previously suggested by several series, including in immunocompromised patients in whom empirical treatment of all potential etiologies may be detrimental [11], [12], [13], [14], [17] and in early-stage ARDS of suspected noninfectious origin [18]. In addition, despite many theoretical
Conclusion
Surgical OLBs may be safely performed at the bedside of mechanically ventilated patients with ARDS of unknown etiology after extensive diagnostic process and despite empirical therapeutic trials, particularly if they are immunocompromised. The procedure is associated with a high diagnostic yield leading to specific modifications of the management of the patients, including withdrawal and limitation of futile care in a majority of them.
References (27)
- et al.
Lung biopsy in immunocompromised hosts
Am J Med
(1975) - et al.
Open lung biopsy in immunocompromised patients
Chest
(1984) - et al.
The role of open-lung biopsy in ARDS
Chest
(2004) - et al.
The utility of open lung biopsy in patients requiring mechanical ventilation
Chest
(1999) - et al.
Lingular and right middle lobe biopsy in the assessment of diffuse lung disease
Ann Thorac Surg
(1987) - et al.
Prospective evaluation of aspiration needle, cutting needle, transbronchial, and open lung biopsy in patients with pulmonary infiltrates
Ann Thorac Surg
(1981) - et al.
Utility of transbronchial biopsy in patients with acute respiratory failure: a postmortem study
Chest
(1998) - et al.
Outcomes and safety of surgical lung biopsy for interstitial lung disease
Chest
(2005) - et al.
Thirty years of clinical trials in acute respiratory distress syndrome
Crit Care Med
(2000) - et al.
Ventilatory management of acute respiratory distress syndrome: a consensus of two
Crit Care Med
(2004)