What is PWTT?
Nihon Kohden monitors incorporate one of our parameters, PWTT (Pulse Wave Transit Time), which can have correlation with blood pressure. The monitor continuously calculates PWTT from ECG and SpO2. During periodic NIBP measurement, if PWTT exceeds the threshold it triggers NIBP measurement. This increases the chance to detect sudden change in blood pressure between periodic NIBP measurements. Together with periodic NIBP measurement, this can provide more complete blood pressure monitoring.
Periodic NIBP measurement is only measured at specified times so sudden critical blood pressure changes that occur between the periodic measurements may be missed until the next periodic measurement.
Nihon Kohden's innovative PWTT technology could solve this problem. With PWTT, if sudden blood pressure change occurs between periodic NIBP measurements, PWTT can detect it and trigger an NIBP measurement to confirm it.
PWTT has a correlation with blood pressure in most cases. However it cannot catch all instances of blood pressure change. See the "Measurement Limitations" section for more details. With recognition of these limitations, PWTT can be a valuable enhancement to noninvasive blood pressure monitoring.