Accuracy and dynamic response of disposable pressure transducer-tubing systems

Accuracy and dynamic response of seven different disposable saline-filled transducer-tubing systems were evaluated in two configurations; a pole-mount version (60-inch tubing) and patient-mount version (12-inch tubing). Natural frequencies (Fn) and damping coefficients were measured as were pressure waveform recordings. A 0.03 ml air bubble was inserted into the different systems in close proximity to the transducer and measurements were repeated. There were dramatic changes in dynamic response with lengthening of tubing to a pole-mount configuration and air bubble additions. Only one transducer-tubing system had adequate accuracy and dynamic response in both the pole- and patient-mount version. Pressure waveforms in the pole-mount versions and with the air bubble produced systolic overshoots up to 35 mmHg. The performance characteristics dictate that the choice for a disposable transducer-tubing system must be made not only by design, but dynamic response which is directly related to clinical set-up.