Use of an Extended Working Channel in high-risk Transbronchial Biopsy- A simple innovation to enhance safety

Background: Transbronchial lung biopsy (TBBx) is a useful diagnostic procedure. Bleeding is the most feared complication of TBBx, seen more commonly with coagulopathy, renal dysfunction, thrombocytopenia and pulmonary hypertension. We hypothesized that TBBx performed through a guide sheath (GS), using it as an extended working channel (EWC) provides tamponade in the vicinity of the biopsy site, restricting bleeding to a smaller segment, and preventing worsening hypoxemia and its consequences in this high-risk subset. Objectives: Examine the protective effect of the EWC in reducing spillover bleeding/hypoxemia in high-risk patients. Methods: TBBx was performed through a GS (EWC) in high risk patients (EWC-HR-TBBx) over 4.5 years. High-risk groups were defined as those with “hypoxia’ ( SpO2 1.5 or BUN > 25,), thrombocytopenia ( 40 mm Hg), systolic/diastolic cardiac dysfunction/valvular heart disease deemed high-risk by a cardiologist, or a combination of the above. Diagnostic yield was also analyzed. Results: Of 804 TBBx in the study period, 105 (13.1%) high-risk procedures qualified for EWC-HR-TBBx. No significant bleeding or worsening hypoxemia was encountered with this strategy. Histopathology revealed adequate sampling in all cases. Conclusion: A GS as an EWC as a ‘distal tamponade’ strategy can be used to reduce the bleeding risk in TBBx in high-risk patients. This simple innovation expands the spectrum of TBBx to high-risk subsets by preventing bleeding and resultant hypoxemia, without compromising sampling quality.