Invasive Tracheal Techniques
Suctioning the bronchotracheal tree in patients with an endotracheal
or tracheotomy tube is a common procedure that may be helpful in removing retained
secretions in patients who have difficulty clearing the airway.[50]
Nasotracheal suctioning in patients without a tracheal tube should be done cautiously
and should not be performed routinely. Airway suctioning has potential complications,
including hypoxemia, hemodynamic instability, cardiac arrhythmia, agitation, airway/vocal
cord trauma, bacterial contamination, and laryngospasm.[53]
Proper technique can limit these potential complications.
The patient should first be assessed to assure cardiopulmonary
stability. The patient should then be preoxygenated with high FIO2
to increase reserve. Next, a sterile,
soft suction catheter is gently advanced through the nose or tracheal tube. The
external diameter of the catheter should be less than half the internal diameter
of the airway to avoid trauma to the airways, decrease the potential for obstructing
a bronchus, and prevent collapse due to over-suctioning. Gentle suction is then
applied while the catheter is withdrawn using a rotating motion. The total suction
time should be less than 20 seconds. The patient should then be re-oxygenated and
reassessed. In ventilated patients, a closed-system suction catheter may minimize
contamination of the airways.
Bronchoscopy is frequently used in the ICU to suction out retained
bronchial secretions in patients with atelectasis. A number of case series have
shown bronchoscopy to be variably effective in treating atelectasis, with published
success rates ranging from 19% to 89%. Patients with lobar collapse seem to respond
better than patients with segmental or subsegmental atelectasis, because central
mucus plugs are more amenable to removal through a bronchoscope.[54]
Some authors have suggested that selective insufflation through the bronchoscope
after removing the mucus plug may further increase the success rate.
It is unclear whether bronchoscopy is superior to other forms
of bronchial hygiene therapy for treating atelectasis. In one small clinical trial
there was no difference in the rate of atelectasis resolution between patients treated
with aggressive chest physiotherapy and patients treated with bronchoscopy.[55]
Given its expense, need for a skilled operator, and invasive nature, bronchoscopy
is usually reserved for patients with lobar or whole lung collapse that has been
refractory to other components of bronchial hygiene therapy.
