Heated air humidification versus cold air nebulization in newly tracheostomized patients

Abstract

BackgroundAfter tracheostomy, the airway lacks an essential mechanism for warming and humidifying the inspired air with the consequent functional impairment and discomfort. The purpose of this study was to compare airway hydration with cold‐air nebulization versus heated high‐flow humidification on medical interventions and tracheal ciliary beat frequency (CBF).MethodsNewly tracheostomized patients (n = 20) were treated either with cold‐air nebulization or heated humidification. The number of required tracheal suctioning procedures to clean the trachea and tracheal CBF were assessed.ResultsThe number of required suctions per day was significantly lower in the heated humidification group with medians 3 versus 5 times per day. Mean CBF was significantly higher in the heated humidification group (6.36 ± 1.49 Hz) compared to the cold‐air nebulization group (3.99 ± 1.39 Hz).ConclusionThe data suggest that heated humidification enhanced mucociliary transport leading to a reduced number of required suctioning procedures in the trachea, which may improve postoperative patient care.

Rapid changes in mucociliary transport in the tracheal epithelium caused by unconditioned room air or nebulized hypertonic saline and mannitol are not determined by frequency of beating cilia

“…This removes water from the mucus layer by evaporation, which in turn lowers the surface temperature, and ultimately causes the mucus to become more viscous [ 31 , 32 ]. Mucus with greater viscosity may interfere with the cilia’s ability to propel it along the surface, which can result in mucus accumulation and the need for suctioning in patients with tracheostomy [ 7 ]. With prolonged exposure, the protective function of the mucus layer lessens and thermal changes would begin to affect the beating cilia underneath, causing cilia activity to decline [ 13 ].…”

“…In contrast, patients breathing room air through the stoma in the trachea forces the tracheobronchial epithelium to take over much of the air conditioning, causing the mucosa to have a greater water loss as it would need to add 85% of the total water required to achieve RH 100% in the main bronchi [ 6 ]. The increased water demand from tracheobronchial epithelium is not well compensated, which results in thick secretions and impaired mucociliary transport [ 7 – 11 ]. These symptoms are commonly found in patients with tracheostomy unless careful attention is given to heating and humidifying inspired air.…”

Flow of Room Air Leads to Rapid Changes in Mucociliary Transport in the Tracheal Epithelium

“…This removes water from the mucus layer by evaporation, which in turn lowers the surface temperature, and ultimately causes the mucus to become more viscous [21,22]. Mucus with greater viscosity may interfere with the cilia's ability to propel it along the surface, which can result in mucus accumulation and the need for suctioning in patients with tracheostomy [7]. With prolonged exposure, the protective function of the mucus layer lessens and thermal changes would begin to affect the beating cilia underneath, causing cilia activity to decline [13].…”

“…In contrast, patients breathing through the stoma in the trachea forces the tracheobronchial mucosa to take over much of the air conditioning, causing the mucosa to have a greater water loss as it is now required to add 85% of the total water required to achieve RH 100% in the main bronchi [6]. The increased water demand from tracheobronchial epithelium is not well compensated, which results in thick secretions and impaired mucociliary transport [7][8][9][10][11]. These symptoms are commonly found in patients with tracheostomy unless careful attention is given to heating and humidifying inspired air.…”

Rapid changes in mucociliary transport in the tracheal epithelium caused by unconditioned room air or nebulized hypertonic saline and mannitol are not determined by frequency of beating cilia

“…In contrast, patients breathing room air through the stoma in the trachea forces the tracheobronchial epithelium to take over much of the air conditioning, causing the mucosa to have a greater water loss as it would need to add 85% of the total water required to achieve RH 100% in the main bronchi [6]. The increased water demand from tracheobronchial epithelium is not well compensated, which results in thick secretions and impaired mucociliary transport [7][8][9][10][11]. These symptoms are commonly found in patients with tracheostomy unless careful attention is given to heating and humidifying inspired air.…”