Advanced life systems hardware development for future missions

An examination of the pulse formation in an externalized vessel suggests that the vessel does not behave as a simple visco-elastic tube. Pressure-pulse waveform transducers are sensitive either to the pressure present at the vessel wall or to the volume of blood filling a region of tissue. Results of comparisons between intra-and extra-vascular pressure recordings suggest that changes in vasomotor tone and transducer-vessel pressures may be the greatest contributors to the divergence of extra-vascular waveforms from intra-vascular waveforms.