During an intubation procedure, endotracheal tubes can be placed in patients who are unable to effectively maintain life-sustaining ventilation and respiration on their own. An endotracheal tube is used in patient care to ensure a clear airway through the mouth, pharynx, and trachea into the lungs. Use of an endotracheal tube is appropriate when the integrity of the airway is, or may become, challenged due to trauma or pathology, or if a patient cannot otherwise breathe unaided. Often the endotracheal tube is coupled to a mechanical ventilator to aid the patient's respiration, and can be expected to remain in situ for an extended time until the patient is once again able to breathe on his or her own. The endotracheal tubes can be inserted within a patient's native airway for short periods of time (e.g., for a matter of hours during anesthesia for surgery) or the endotracheal tubes can remain in place to provide ventilator-assisted breathing for days or weeks.
The institution of mechanical ventilation can result in increased production of secretions within the patient's native airways and accumulation of those secretions within an artificial airway such as an endotracheal tube. The insertion of an endotracheal tube within the patient's trachea renders the normal cough mechanism for clearing of secretions ineffective, as the patient cannot transiently close the glottis to build up pressure in the airway that, when released, helps expel secretions. Also, the mucociliary system which helps transport secretions and debris from the tracheobronchial tree into the trachea for expectoration becomes ineffective in the sick, intubated patient. The secretions, therefore, can pool in dependent portions of the lung over time due to gravity and, if not removed in a timely manner, can result in ventilator-acquired pneumonia (VAP) or other undesired conditions or ailments. Closed suction systems may be coupled to the endotracheal tube and a suction catheter may be used to suction out the pooled secretions or other debris within the patient's native airways and/or the endotracheal tube. Intraluminal volume loss attributable to the accumulation of secretions on the interior wall of endotracheal tubes is not prevented by standard suctioning treatment. Secretion accumulation can lead to life-threatening occlusion of the endotracheal tube or at least increased work of breathing, which may result in increased difficulty in weaning, and prolonged mechanical ventilation and intensive care unit stay. Additionally, secretion accumulation on the inside of the endotracheal tube leads to colonization with potentially pathological organisms and this colonization is likewise implicated in the development of VAP.
Bronchoscopes are typically used to visualize the patient's airways. In order to insert the bronchoscopes within the patient's mouth and into (and possibly through) the endotracheal tube, the standard closed suction system must be removed, thereby at least temporarily removing the patient from the ventilator, which may not be feasible for patients with high ventilatory requirements. In addition, due to the large diameter of most bronchoscopes, air travel through the endotracheal tube may be substantially blocked during the visualization procedure.