Prevention of obstruction of nasopharyngeal CPAP tubes by adequate humidification of inspired gases.

Nasopharyngeal CPAP is a simple and useful technique for increasing FRC and stimulating respiration in small premature infants. However, as it is essentially a non-rebreathing technique, the gases used should be warmed and saturated to the level normally found in the pharynx with no artificial airway present (31 degrees to 33 degrees C, 90 per cent plus relative humidity). If this is not done, crusting, mucous plugging, atelectasis, hypoxia, and infection will occur rapidly. Excess humidity should also be avoided.