Bronchoscopy is an important and useful tool in the management and care of critically patients.
Bronchoscopy can aid in diagnosing pulmonary pathology by direct visualization of the tracheobronchial tree as well as acquisition of deep sampling for culture or in select cases, tissue biopsy.
Clinicians need to be aware of the physiologic effects, indications, contraindications and complications of bronchoscopy so that patients can be properly selected and derive benefit from the procedure.
In 1897, Gustav Killian first viewed the trachea and mainstem bronchi via a rigid tube, the prototype for the rigid bronchoscope. Later that year, he removed a bone from the right mainstem of one of his patients, the first known therapeutic use of the bronchoscope. In the early 1900s, Chevalier Jackson added an electrical light source to the distal end of the bronchoscope as well as a suction channel. The flexible bronchoscope was first used in clinical practice in 1967 by Shigeto Ikeda in Japan and by the late 1980s, the videobronchoscope was introduced by Asahi Pentax. For the first time this allowed for visualization of the airways on a screen rather than through the eyepiece of the scope.
Flexible fiberoptic bronchoscopy is an integral and vital skill and has become a common procedure in the intensive care unit (ICU). It allows for real-time imaging of the airways from the vocal cords to the subsegmental bronchi. It can be diagnostic and/or therapeutic such as for airway inspection, foreign body removal, suctioning of secretions, collection of samples and placement of devices or drugs within the airway.
PHYSIOLOGIC EFFECTS OF BRONCHOSCOPY
Bronchoscopy is not a physiologically neutral procedure and continuous monitoring of heart rate, blood pressure and oxygenation must be done during and after the procedure. In ICU patients, ventilator parameters are also monitored to ensure that adequate tidal volumes are delivered and airway pressures are not excessively elevated. The following changes must be taken into account and anticipated during bronchoscopy.
Increased airway resistance. Partial occlusion of the airway by a bronchoscope can increase airway resistance, which can effect peak inspiratory pressure (PIP) and positive end-expiratory pressure (PEEP) as well as delivered tidal volume. These changes can have hemodynamic consequences in patients who may already have cardiovascular instability.
Decreased lung compliance. Bronchoscopy can decrease lung compliance by alveolar collapse from suctioning or surfactant loss after bronchoalveolar lavage (BAL). These effects can be especially significant in patients with decreased compliance, such as acute respiratory distress syndrome (ARDS), pneumonia, atelectasis, and chronic obstructive pulmonary disease (COPD).
Gas exchange. The most common gas exchange abnormality is transient hypoxemia from airway obstruction, alveolar collapse, fluid within the alveoli during BAL or bronchospasm. Oxygenation is likely to worsen in a critically ill patient because of the bronchoscope in the airways or endotracheal tube (ETT) ...