Effect of electronic compensation on plethysmographic airway resistance measurements.

Objectives: To compare the performance of a plethysmograph which incorporated electronic compensation (Jaeger) to one which incorporated a heated humidified breathing system (Hammersmith plethysmograph).

Working Hypothesis: The performance of a plethysmograph which incorporated electronic compensation would be impaired compared to that which incorporated a heated humidified system.

Study Design: In vitro and in vivo comparison.