Noninvasive blood pressure determination method and apparatus

An apparatus for noninvasively determining of a blood pressure (P) of a patient (2), comprising

• a) an ECG sensor (3;
• 18) for detecting an electrical cardiac potential measurement signal (EM);
• b) a pulse sensor (4;
• 19) for detecting a pulse measurement signal (PM) of a pulse pressure wave which, starting from the heart, propagates within the blood vessels as far as to a pulse-feeling location (15) where the pulse sensor (4;
• 19) is disposed;
• c) an evaluation unit (6) for determining a propagation time (T) of the pulse pressure wave between the heart and the pulse-feeling location (15) on the basis of the electrical measurement signal (EM) and the pulse measurement signal (PM);
• d) wherein the evaluation unit (6) is designed for determining the blood pressure (P) from the propagating time (T) by means of a function interrelationship which comprises a first portion that specifies the active elasticity behaviour of the blood vessels, and a second portion that specifies the passive elasticity behaviour of the blood vessels.