Hemodynamic relationships among upper-abdominal aorta and femoral arteries: basis for measurement of arterial blood flow to abdominal-pelvic organs.

Background: Arterial blood flow (BF) to all abdominal-pelvic organs (AP) is a potentially useful indicator of splanchnic circulatory dysfunction or various stress-induced AP flow distributions. BFAP can be measured by subtracting BF in the "peripheral" bilateral limb left/right-femoral arteries (FA) from the "central" upper abdominal aorta (Ao) above the celiac trunk according to the formula: BFAP = BFAo-both BFFAs. It is necessary to understand the hemodynamics of the three-conduit arteries to determine physiological BFAP. The aim was to examine 1) basal hemodynamic parameters such as vessel diameter (VD), blood velocity (BV), and BF and their relationship to Ao and FAs and 2) how both BFAo and BFFAs influence the magnitude of BFAP.

Material/methods: Fifty healthy males with a wide range of body weights were evaluated while seated following a 12-hour fast. Hemodynamics in three-conduit arteries was measured by pulsed Doppler with spectral analysis.

Results: Positive linear relationships in VD, BV, and BF were observed between Ao and both FAs (r value range: 0.399-0.529) and between BFAo and limb BFFAs (sum of both BFFAs; r=0.544, p<0.0001). BFAP was more strongly proportional to BFAo (r=0.966, p<0.0001) than BFFAs (r=0.303, p=0.0327 in LFA, r=0.281, p=0.0482 in RFA). BFAP was thus expressed as: BFAP (l/min) = 0.85 x BFAo-0.19.

Conclusions: Under basal conditions, biological proportion and close hemodynamic relationship were observed between Ao and FAs. Consequently, BFAP was more strongly influenced by BFAo than by BFFAs. BFAP may be potentially evaluated by BFAo to determine single arterial hemodynamics using the above formula.