The Utility of Open Lung Biopsy in Patients Requiring Mechanical Ventilation: Discussion
Open lung biopsy established a specific diagnosis in 46% of the patients in this series, all of whom were critically ill and with ventilator-dependent respiratory failure. As a result of the findings from the open lung biopsy, alteration in therapy (including withdrawal of therapy) occurred in 75% of the patients, and of these, 39% survived. Another 11% benefited from the avoidance of unnecessary, prolonged, and futile therapy. No patient with > 2 other organ failures benefited from an alteration in therapy, despite a specific diagnosis from an open lung biopsy.
Open lung biopsy findings may have contributed positively to the outcome of survivors from the nonspecific diagnosis group who subsequently received steroid therapy, as has been suggested else-where.
The effect of the timing of an open lung biopsy, in relation to the patients’ illness and eventual outcome, is not clearly defined. Rossiter et al suggested that an early open lung biopsy carries a survival advantage; however, Bove et al did not show a statistically significant difference between their survival and nonsurvival groups in the timing of the open lung biopsy . In the study by Rossiter et al an open lung biopsy performed within 10 days of hospital admission tended toward a survival advantage. Their results, however, did not attain statistical significance. Outcome in immunocompromised patients is influenced by the time to initiation of appropriate therapy, highlighting the importance and urgency in making a definitive diagnosis in this group Source purchase zyrtec. This study did not establish an effect of the timing of open lung biopsy on outcome, and there was not a statistical difference between the survivors and nonsurvivors for immunosuppression.
Classification of a specific diagnosis varies among studies of patients undergoing open lung biopsy. Cheson et al reviewed 10 studies performed before 1983. The range for a specific diagnosis is 55% to 95%, but the definitions differ among the various studies. In their own study, using criteria for histological diagnosis that are similar to those used in this study, a specific diagnosis was found in 71% of the patients compared to 46% in this study. All or a large proportion of these patients were not receiving mechanical ventilation, which itself can result in lung injury and abnormal histological changes.” The error rate in this study was 4%. This error rate compares with rates of 12%, 3.4%,2 and 3% that have been found elsewhere.