ETCare: Safety and Preliminary Efficacy Trial

Normal saline (0.9% sodium chloride) is used by virtually all neonatal intensive care units to periodically irrigate the endotracheal tube of neonates who require mechanical ventilation. This practice is intended to reduce the risk that thick secretions will occlude the endotracheal tube. Normal saline is also occasionally used to periodically clear the nasal passages of neonates on nasal CPAP or nasal canula oxygen. It is also occasionally used as a means of periodically moistening the mouth of neonates who have an endotracheal tube in place, because the tube prevents lip apposition and results in a dry mouth. The problem with the current method of using normal saline for periodic endotracheal, nasal, and/or oral care is that high concentrations of sodium and chloride have recently been found to rapidly and completely inactivate the natural antimicrobial properties of tracheal effluent, nasal secretions, and saliva. Tracheal secretions, nasal secretions, and saliva contain potent antibacterial substances. One such that was recently described is a 37 amino acid peptide with widespread antimicrobial properties, termed "LL-37". It has recently been shown that 0.9% saline inactivates the antimicrobial properties of LL-37 and significantly damages the overall antibacterial actions of tracheal secretions, nasal secretions, and saliva. Further research has shown that the high sodium and chloride content of saliva of patients with cystic fibrosis inactivates the antimicrobial properties, thus partly explaining the high incidence of airway infections in these patients. Moreover, a family with deficient LL-37 has been described in Sweden, and these individual all have chronic gingivostomatitis and airway infections. Therefore, our current practice of instilling 0.9% sodium chloride likely inactivates the major innate anti-microbial defense system of the upper airway. Perhaps reducing immune capacity in the upper airway with this practice unwittingly contributes to the high incidence of upper airway infections among intubated neonates.