Introduction
Severe traumatic brain injury is often accompanied with different
degrees of respiratory disorders, thus resulting in hypoxic asphyxia,
elevated intracranial pressure, and these conditions further deteriorate
the disease. Tracheotomy, which established an artificial airway, could
maintain respiratory tract patency and is a key operation for the early
treatment of severe traumatic brain
injury1. During normal
breathe, the upper respiratory tract will warm and wet the inhaled gas.
But when an artificial airway is established, the warming and
humidification effects of the patients’ respiratory tract is destroyed,
the dry gas can further damage the trachea and bronchial
mucosa2, and the
movement of respiratory cilia was affected, which causing respiratory
tract blockage, pulmonary dilatation, pneumonia, posterior pituitary
dysfunction and the following cognitive dysfunction3-5. Therefore, the gas
must be humidified before inhaled in, that is, airway humidification,
and previous study had proved that heated humidification improves
clinical outcomes in children with tracheostomies 6.
And study recommended humidification in both invasive and noninvasive
mechanical ventilation7,
which suggested that humidification is essential for airway protection.
At present, there are many methods for airway humidification applied in
clinical. Each method has its own disadvantage8-10, so comparative
studies had been carried out, for instance, studies had compared the
advantages of Heat and moisture exchanger (HME) and heated humidifiers
(HHs) in adults and children need mechanically ventilation, though no
difference was found in their study, the authors suggested further
comparing of HMEs to HHs in paediatric and neonatal
patients11. To date,
the studies but was not sufficient, especially for some specific
disease. Therefore, it is urgent to carry out systematic evaluation of
some other humidification methods that frequently used in clinical, and
to find out the most suitable method for airway humidification in
patients with severe traumatic brain injury. In view of the fact that
the common airway humidification method has been used in patients with
severe traumatic brain injury in neurosurgery, and its advantages and
disadvantages had also been experienced in our hospital, we chose three
most respected methods in the world for comparison. We aim to select the
most suitable method of airway humidification for patients with severe
brain injury.