Determination of regional pulmonary blood flow with systemically
injected, nonentrapped radioactive microspheres.
Kleen, M., B. Zwissler, R. Schosser, and K. Messmer.
Institute for Surgical Research and Institute of Anesthesiology,
University of Munich, Marchioninistr 15, 81366 Munich, Germany and
Immuno GmbH, Im Breitspiel 13, 69126 Heidelberg, Germany
APStracts 3:0163A, 1996.
Radioactive microspheres (MS) injected into the systemic circulation
shunt to the venous side of the circulation and are trapped in the
lung vasculature. We hypothesized that regional pulmonary perfusion
could be determined using systemically injected, shunted MS. In seven
anesthetized, mechanically ventilated foxhounds regional pulmonary
perfusion was measured at baseline and during experimental acute
respiratory distress syndrome (eARDS) with MS injected into both the
right and left atrium (Protocol 1). Methodological error of the MS
technique was assessed by simultaneous injection of two different
batches of MS into the right atrium (Protocol 2). Measurement of
perfusion during baseline and during eARDS with shunted MS had a mean
bias of 0.8% and 5.6%, respectively, and mean precision of 19.2% and
34.7%, respectively (r=0.94 or r=0.95), when compared to data from
non-shunted MS. Simultaneous perfusion measurements displayed bias of
-2.7% and 6% and precision of 8.2% and 5.3% (r=0.98, r=0.99).
Systemic shunt should be high for this method in order to prevent
bronchial circulation to impose significant error. We conclude that
systemically injected MS can be used for simultaneous measurement of
regional systemic and regional pulmonary perfusion, provided that MS
that shunted in the first pass are measured in lung tissue.
Received 9 August 1995; accepted in final form 22 February 1996.
APS Manuscript Number A871-5.
Article publication pending Journal of Applied Physiology.
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 27 March 96