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Updated: Aug 11, 2026

Assessment of Pulmonary Capillary Blood Volume, Membrane Diffusing Capacity, and Intrapulmonary Arteriovenous Anastomoses During Exercise
Published on: February 20, 2017
A noninvasive method for estimating cardiac output using lung to finger circulation time of oxygen
B Kasravi1, J P Boehmer, U A Leuenberger
1Section of Cardiology, Penn State University College of Medicine, Milton S. Hershey Medical Center, Hershey, Pennsylvania 17033-0850, USA.
Abstract:
To develop a safe, noninvasive, simple, inexpensive, and clinically adaptable method for estimating cardiac output, we evaluated the potential of lung to finger circulation time (LFCT) and buildup time (Tb) of oxygen as measured by pulse oximetry to estimate cardiac output. Significant correlation was found between cardiac output as measured by thermodilution and the inverse of LFCT (R = 0.76, p < 0.001, SEE = 0.9 L/min) as well as the inverse of Tb (R = 0.72, p < 0.001, SEE = 0.9 L/min).
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