Mechanically ventilated patients in
respiratory failure often require adjunct
therapies to address special needs such as inhaled
drug delivery to alleviate
airway obstruction, treat pulmonary
infection, or stabilize gas exchange, or
therapies that enhance pulmonary hygiene. These
therapies generally are supportive in nature rather than curative. Currently, most lack high-level evidence supporting their routine use. This overview describes the rationale and examines the evidence supporting adjunctive
therapies during
mechanical ventilation. Both mechanistic and clinical research suggests that intrapulmonary percussive ventilation may enhance pulmonary secretion mobilization and might reverse
atelectasis. However, its impact on outcomes such ICU stay is uncertain. The most crucial issue is whether aerosolized
antibiotics should be used to treat
ventilator-associated pneumonia, particularly when caused by multi-
drug resistant pathogens. There is encouraging evidence from several studies supporting its use, at least in individual cases of
pneumonia non-responsive to systemic
antibiotic therapy. Inhaled pulmonary
vasodilators provide at least short-term improvement in oxygenation and may be useful in stabilizing pulmonary gas exchange in complex management situations. Small uncontrolled studies suggest aerosolized
heparin with
N-acetylcysteine might break down pulmonary casts and relieve
airway obstruction in patients with severe inhalation injury. Similar low-level evidence suggests that
heliox is effective in reducing airway pressure and improving ventilation in various forms of lower
airway obstruction. These
therapies generally are supportive and may facilitate patient management. However, because they have not been shown to improve patient outcomes, it behooves clinicians to use these
therapies parsimoniously and to monitor their effectiveness carefully.