In vivo inductive phase shift measurements to detect intraperitoneal fluid.
Four different volumes of physiological saline were infused into the abdominal cavity of rats and the resulting inductive phase shift in the bulk of the abdomen was measured with a noncontact electrical induction system, built to measure phase shift in the bulk of the body in the frequency range from 1 MHz to 8.5 MHz. This experimental study shows that inductive bulk measurements of phase shift have the potential to detect changes in intraperitoneal fluid in vivo with measurements made at frequencies higher than approximately 1 MHz. The experiments also show that the bulk phase shift increases as a function of frequency and fluid volume in a way that is qualitatively consistent with earlier theoretical predictions.
González
César A
CA
Universidad del Ejército y Fuerza Aérea-Sedena, DF, México. gonzalezantoni@hotmail.com
Horowitz
Liana
L
Rubinsky
Boris
B
D000818:Animals; D001826:Body Fluids / Q000502:physiology*; D001835:Body Weight; D003198:Computer Simulation; D017097:Electric Impedance; D055590:Electromagnetic Phenomena / Q000379:methods; D004594:Electrophysiology / Q000379:methods*; D007260:Infusion Pumps; D007263:Infusions, Parenteral; D007552:Isotonic Solutions / Q000737:chemistry; D008297:Male; D008962:Models, Theoretical; D051381:Rats; D017207:Rats, Sprague-Dawley; D012965:Sodium Chloride / Q000008:administration & dosage / Q000737:chemistry; D013057:Spectrum Analysis / Q000295:instrumentation / Q000379:methods
D007552:Isotonic Solutions; D012965:Sodium Chloride