Capacitive Air Bubble Detector Operated at Different Frequencies for Application in Hemodialysis
Air bubbles have been detected in human circulation
of end-stage renal disease patients who are treated by hemodialysis.
The consequence of air embolism, air bubbles, is under recognized
and usually overlooked in daily practice. This paper shows results of
a capacitor based detection method that capable of detecting the
presence of air bubbles in the blood stream in different frequencies.
The method is based on a parallel plates capacitor made of platinum
with an area of 1.5 cm2 and a distance between the two plates is 1cm.
The dielectric material used in this capacitor is Dextran70 solution
which mimics blood rheology. Simulations were carried out using
RC circuit at two frequencies 30Hz and 3 kHz and results compared
with experiments and theory. It is observed that by injecting air
bubbles of different diameters into the device, there were significant
changes in the capacitance of the capacitor. Furthermore, it is
observed that the output voltage from the circuit increased with
increasing air bubble diameter. These results demonstrate the
feasibility of this approach in improving air bubble detection in
Hemodialysis.
[1] Michal Barak, Farid Nakhoul, and Yeshayahu Katz. Pathophysiology
and Clinical Implications of Micro Bubbles during Hemodialysis.
Seminars in Dialysis. 2008; 21: 232-238.
[2] Bischel MD, Scoles BG, Mohler JG. Evidence for Pulmonary
Microembolization during hemodialysis. Chest. 1975; 67: 335-337.
[3] Vivian WA, Malloy KP, Hackett JE, et al. Clinical evaluation of an air
embolism detection device. Cardiovasc Dis 1980; 7:425-428.
[4] Nebuya S, Noshiro M, Brown BH, et al. Estimation of the size of air
emboli detectable by electrical impedance measurement. Med Biol Eng
Comput 2004; 42:142-144.
[5] Markus H. Transcranial Doppler detection of circulating cerebral
emboli: a review. Stroke 1993; 24:1246-1250.
[6] Giorgio Rizzoni (2000), Principles and Applications of Electrical
Engineering McGraw-Hill Higher Education.
[7] Robert L. Boylestad and Louis Nashelsky(2006),Electronic Devices and
Circuit Theory. Ninth Edition.
[8] Christorfer J. Stegmayr, Per Jonsson, Ulf Forsberg and Bernd G.
Stegmayr (2007), Development of Air Micro Bubbles in the Venous
Outlet Line: an in Vitro Analysis of Various Air Traps Used for
Hemodialysis. Journal of Artif Organs, 31, 483-488.
[1] Michal Barak, Farid Nakhoul, and Yeshayahu Katz. Pathophysiology
and Clinical Implications of Micro Bubbles during Hemodialysis.
Seminars in Dialysis. 2008; 21: 232-238.
[2] Bischel MD, Scoles BG, Mohler JG. Evidence for Pulmonary
Microembolization during hemodialysis. Chest. 1975; 67: 335-337.
[3] Vivian WA, Malloy KP, Hackett JE, et al. Clinical evaluation of an air
embolism detection device. Cardiovasc Dis 1980; 7:425-428.
[4] Nebuya S, Noshiro M, Brown BH, et al. Estimation of the size of air
emboli detectable by electrical impedance measurement. Med Biol Eng
Comput 2004; 42:142-144.
[5] Markus H. Transcranial Doppler detection of circulating cerebral
emboli: a review. Stroke 1993; 24:1246-1250.
[6] Giorgio Rizzoni (2000), Principles and Applications of Electrical
Engineering McGraw-Hill Higher Education.
[7] Robert L. Boylestad and Louis Nashelsky(2006),Electronic Devices and
Circuit Theory. Ninth Edition.
[8] Christorfer J. Stegmayr, Per Jonsson, Ulf Forsberg and Bernd G.
Stegmayr (2007), Development of Air Micro Bubbles in the Venous
Outlet Line: an in Vitro Analysis of Various Air Traps Used for
Hemodialysis. Journal of Artif Organs, 31, 483-488.
@article{"International Journal of Electrical, Electronic and Communication Sciences:51432", author = "Mawahib Gafare Abdalrahman Ahmed and Abdallah Belal Adam and John Ojur Dennis", title = "Capacitive Air Bubble Detector Operated at Different Frequencies for Application in Hemodialysis", abstract = "Air bubbles have been detected in human circulation
of end-stage renal disease patients who are treated by hemodialysis.
The consequence of air embolism, air bubbles, is under recognized
and usually overlooked in daily practice. This paper shows results of
a capacitor based detection method that capable of detecting the
presence of air bubbles in the blood stream in different frequencies.
The method is based on a parallel plates capacitor made of platinum
with an area of 1.5 cm2 and a distance between the two plates is 1cm.
The dielectric material used in this capacitor is Dextran70 solution
which mimics blood rheology. Simulations were carried out using
RC circuit at two frequencies 30Hz and 3 kHz and results compared
with experiments and theory. It is observed that by injecting air
bubbles of different diameters into the device, there were significant
changes in the capacitance of the capacitor. Furthermore, it is
observed that the output voltage from the circuit increased with
increasing air bubble diameter. These results demonstrate the
feasibility of this approach in improving air bubble detection in
Hemodialysis.", keywords = "Air bubbles, Hemodialysis, Capacitor, Dextran70,Air bubbles diameters.", volume = "3", number = "2", pages = "183-4", }