Non-invasive blood pressure measurement system

An electronic method for monitoring blood pressure of a patient, the method comprising:

• receiving physiological electrical information associated with a patient, the physiological electrical information configured to reflect electrical activity of the patient's heart;
• receiving a cardiac ejection information associated with the patient, the cardiac ejection information reflecting ejection of blood from the patient's heart;
• receiving arterial pulse information associated with a limb of the patient from an acoustic sensor;
• determining an arterial pulse wave transit time (PWTT) measurement that compensates for a pre-ejection period of a cardiac cycle associated with the patient's heart, based at least partly on the physiological electrical information, the cardiac ejection information, and the arterial pulse information;
• receiving a respiratory rate signal that is correlated with a set of arterial PWTT measurements, including the arterial PWTT measurement;
• determining a variability in the received respiratory rate signal;
• adjusting an averaging parameter for an averaging filter configured to be applied to the set of arterial PWTT measurements based on the variability;
• applying the averaging filter to the set of arterial PWTT measurements to thereby selectively reduce noise in the set of arterial PWTT measurements;
• and
• monitoring blood pressure of the patient based on the application of the averaging filter to the set of arterial PWTT measurements.