Title :
Basic considerations of ultrasonic air-bubble detectors for blood extracorporeal circulation
Author :
Costa, Luiz Eduardo G da ; Machado, João C.
Author_Institution :
Biomedicai Engineering Program - COPPE/Federal University of Rio de Janeiro, P.O. BOX 68510 - 21945 Rio de Janeiro, R.J. Brazil
fDate :
Oct. 29 1992-Nov. 1 1992
Abstract :
This work presents an analysis about the limitation of ultrasonic air-bubble detectors based on the measurement of the wave attenuation caused by the presence of air-bubbles in the blood circuit. Considering as a lower limit the amount of 0.5 ml of air in 1 liter of blood for a blood flow rate of 250 ml/min then it is shown that for ultrasonic frequencies of 50 kHz, 100 kHz, 1 MHz and 5 MHz the detectors may fail if the air-bubble diameter exceeds 110, 74, 44 and 38 μm, respectively.
Keywords :
Acoustics; Biomedical measurements; Blood; Frequency measurement; Ultrasonic variables measurement;
Conference_Titel :
Engineering in Medicine and Biology Society, 1992 14th Annual International Conference of the IEEE
Conference_Location :
Paris, France
Print_ISBN :
0-7803-0785-2
Electronic_ISBN :
0-7803-0816-6
DOI :
10.1109/IEMBS.1992.5761021
