Which of the following are valid reasons for not using a heat and moisture exchanger in infants?

Question

1. Heat and moisture exchangers add 30 mL to 90 mL of mechanical dead space.
2. Heat and moisture exchangers are not effective with uncuffed endotracheal tubes.
3. Heat and moisture exchangers might cause an obstruction in endotracheal tubes in infants.
4. Heat and moisture exchangers are an inexpensive alternative to humidifiers.
a. 1, 2, and 3 c. 2 and 4
b. 1 and 4 d. 3 and 4

Answer 1

ANS: A
Heat and moisture exchangers are not recommended for use in infants for several reasons. Heat and moisture exchangers add 30 to 90 mL of mechanical dead space, often exceeding the tidal volume of a 5-kg infant (i.e., 25 mL). Uncuffed endotracheal tubes used in infants allow a por-tion of exhaled gas to leak around the tube, bypassing the heat and moisture exchanger and re-ducing its ability to capture exhaled heat and humidity. Providing heated humidity at less than 35? C has been associated with narrowing and obstruction of endotracheal tubes in infants. The advantages of heat and moisture exchangers are that they are inexpensive alternatives to humidi-fiers and they are the best choice for adult patients.