Adjunct Therapies During Mechanical Ventilation: Airway Clearance Techniques, Therapeutic Aerosols, and GasesDiscussion

Abstract

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 ventilatorassociated 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. Key words: high-frequency percussive ventilation; intrapulmonary percussive ventilation; inhaled nitric oxide; aerosolized prostacyclin; aerosolized heparin; metered-dose inhalers; heliox.

Incidence and predictors of 14-day mortality in multidrug-resistant Acinetobacter baumannii in ventilator-associated pneumonia

“…This is a combined product of ipratropium bromide and salbutamol sulfate that acts on both muscarinic and beta2-adrenergic receptors, respectively, in the lungs, leading to bronchodilation. Most patients on MV have respiratory failure, and this nebulizer improves air flow, relieves underlying inflammatory bronchospasm, and thus achieves better airway protection [28], which potentially could explain this association. Generally, this medication is used as supportive rather than curative therapy during MV to facilitate patient management [28].…”

“…Most patients on MV have respiratory failure, and this nebulizer improves air flow, relieves underlying inflammatory bronchospasm, and thus achieves better airway protection [28], which potentially could explain this association. Generally, this medication is used as supportive rather than curative therapy during MV to facilitate patient management [28]. More clinical studies are needed to explore the association between using a bronchodilator as adjunctive therapy and prognosis in MDR-AB infected cases.…”

Prophylactic Use of Nebulized Hypertonic Saline in Mechanically Ventilated Children: A Randomized Blinded Pilot Study

“…2 Mechanically ventilated patients may have ineffective airway clearance due to multiple mechanisms, including weakened expiratory muscles, ineffective cough, and decreased mucociliary function. 3,4 This can lead to obstructive airway secretions, which may be especially tenacious due to conservative fluid management. 3,5 Obstructive airway secretions may prolong mechanical ventilation by causing atelectasis, inadequate gas exchange, and endotracheal SEE THE RELATED EDITORIAL ON PAGE 716 tube obstruction, with resultant cardio-respiratory instability.…”

Relationship between hyperoxemia and ventilator associated pneumonia

“…Adsorption atelectasis occurs within few minutes after pure O 2 breathing (23)(24)(25). In mechanically ventilated patients, atelectasis seriously impairs cough reflex and mucus clearance resulting in abundant secretions in the lower airways and higher risk for VAP (26,27).…”