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In critical care, a fluid-filled catheter transducer system is commonly used to continuously monitor blood pressure. The fluid-filled catheter transducer system, as a first approximation, behaves as a second order dynamic system. The dynamic characteristics of the system are affected by variations in assembly technique and time dependent changes in the system, often resulting in distortion and inaccurate measurements. A previous simulation study employed a counter pressure source in tandem with the transducer. The counter pressure generated minimized the fluid flow in the pressure monitoring system. When the flow in the system was zero the counter pressure generated closely approximated the true blood pressure. The current study developed a real-time technique to generate accurate and dependable counter pressure. To validate this technique, one experimental model (second order dynamic system) and two simulation models (second order dynamic system and fourth order dynamic system) of catheter transducer system were developed and tested under varying system conditions. The real-time technique developed, successfully reproduced the true blood pressure waveforms, regardless of variations in the system characteristics and changes in the system over time.