. Author manuscript; available in PMC: 2010 Sep 1.

Published in final edited form as: Sleep Med Clin. 2009 Sep;4(3):393–406. doi: 10.1016/j.jsmc.2009.04.007

Table 1.

Airflow Sensors Used In Pediatric Polysomnography

Sensor	Methodology	Advantages	Disadvantages	Recommendation
Thermistor	Detects changes in temperature	Measures oral as well as nasal flow	Provides a qualitative rather than quantitative assessment of airflow	AASM recommends use for detection of apnea
Nasal pressure	Detects changes in nasal pressure	Provides a semi- quantitative assessment of airflow	Poor signal in mouth-breathing patients. Frequently obstructed by secretions etc.	AASM recommends use for detection of hypopnea
End-tidal CO2	Measures PCO₂	Provides a quantitative assessment of the PCO₂.	Poor signal in mouth-breathing patients. Frequently obstructed by secretions etc. May be over-sensitive in detecting airflow.	Use as a quantitative measure of PCO₂ rather than a primary measure of airflow.
Respiratory inductance plethysmography sum signal	Derives tidal volume from changes in inductance of coils	Tolerated well as no sensors on face.	Difficult to maintain calibrated. Cannot distinguish between obstructive apnea and paradoxing from other causes, e.g., in a young child or child with neuromuscular disease.	Useful for assessing respiratory effort in addition to airflow.
Pneumotachometer	Measurement of airflow by measuring pressure differences across a known resistance	Quantitative assessment of airflow	Requires a snug-fitting face mask	Use in CPAP studies