ESTIMATION OF PULMONARY BLOOD FLOW WITH AN ELECTRICAL IMPEDANCE PLETHYSMOGRAPH.
Abstract
An electrical impedance plethysmograph to estimate right ventricular stroke volume and pulmonary blood flow was constructed for use on human subjects. Two circumferential band electrodes were placed around the neck, and two around the abdomen. Stroke volume was calculated from extrapolated slopes of the recorded impedance changes occurring during systole and from physical parameters of the subject. Data were compared with cardiac output determinations obtained by the IDD and Fick procedures. As a result of experimental limitations and physiologic variations, definitive statements about the data correlation are fundamentally difficult to make. However, the impedance estimates of blood flow compared favorably with conventionally determined values for a significant percentage of the 46 cardiac patients examined. The plethysmograph impressed a 100-kcps, 5-ma, current across the thorax. Subjects were insensitive to the measurement but were required to briefly interrupt breathing. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1965
- Accession Number
- AD0478041
Entities
People
- Edwin Kinnen
Organizations
- University of Rochester