Harmonic analysis of perfusion pumps.
The controversy over the use of nonpulsatile versus pulsatile pumps for maintenance of normal organ function during ex vivo perfusion has continued for many years, but resolution has been limited by lack of a congruent mathematical definition of pulsatility. We hypothesized that the waveform frequency and amplitude, as well as the underlying mean distending pressure are all key parameters controlling vascular function. Using discrete Fourier Analysis, our data demonstrate the complexity of the pulmonary arterial pressure waveform in vivo and the failure of commonly available perfusion pumps to mimic in vivo dynamics. In addition, our data show that the key harmonic signatures are intrinsic to the perfusion pumps, are similar for flow and pressure waveforms, and are unchanged by characteristics of the downstream perfusion circuit or perfusate viscosity.
Department of Mechanical Engineering, EGCB 204, University of South Alabama, Mobile, AL 36688, USA. doughert@jaguar1.usouthal.edu
F Carroll
FC
Dougherty
F M
FM
Donovan
Mary I
MI
Townsley
D000818:Animals; D001783:Blood Flow Velocity; D001794:Blood Pressure; D001809:Blood Viscosity; D004285:Dogs; D019544:Equipment Failure Analysis / Q000379:methods*; D005583:Fourier Analysis; D006801:Humans; D007260:Infusion Pumps; D008168:Lung / Q000098:blood supply* / Q000502:physiology*; D008170:Lung Compliance / Q000502:physiology; D008955:Models, Cardiovascular; D009991:Oscillometry / Q000379:methods*; D011673:Pulsatile Flow / Q000502:physiology*