Endobronchial Ultrasound Bronchoscopy in Patients with Acute Respiratory Failure on Noninvasive Ventilation: Report of Two Cases

ABSTRACT

Fiberoptic bronchoscopy (FOB) has simplified the direct examination of the lungs and is widely used for diagnosis and therapy. Fiberoptic bronchoscopes occupy a significant proportion of cross-section area of central airways, which can affect lung mechanics and gas exchanges that may lead to desaturation and cardiac arrhythmia. This makes bronchoscopy in critically ill patients with respiratory failure even more challenging. Use of noninvasive mechanical ventilation (NIV) may help to avoid use of invasive mechanical ventilation in selected patients with acute respiratory failure. It has been shown to be useful in hypoxemic patients to facilitate bronchoscopic examination for bronchoalveolar lavage, bronchial brushing, endobronchial biopsy (EBB), and transbronchial lung biopsy (TBLB). Noninvasive mechanical ventilation has also been used to facilitate other endoscopic procedures including transesophageal echocardiography (TEE) and upper gastrointestinal endoscopy for diagnostic and therapeutic interventions in hypoxemic patients. Endobronchial ultrasound (EBUS) bronchoscope, having a wider diameter than a conventional bronchoscope, may have a more pronounced effect on lung mechanics and gas exchanges, and its use in patients on NIV has not been reported. Contraindications of EBUS are mostly relative and similar to FOB. There are several studies suggesting the safety of NIV-supported FOB in hypoxemic patients. We describe our experience of the first two EBUS bronchoscopies and transbronchial needle aspiration (TBNA) was done in hypoxemic patients with NIV support.