Physiological aspects of the determination of comprehensive arterial inflows in the lower abdomen assessed by Doppler ultrasound

Abstract

Non-invasive measurement of splanchnic hemodynamics has been utilized in the clinical setting for diagnosis of gastro-intestinal disease, and for determining reserve blood flow (BF) distribution. However, previous studies that measured BF in a "single vessel with small size volume", such as the superior mesenteric and coeliac arteries, were concerned solely with the target organ in the gastrointestinal area, and therefore evaluation of alterations in these single arterial BFs under various states was sometimes limited to "small blood volumes", even though there was a relatively large change in flow. BF in the lower abdomen (BFAb) is potentially a useful indicator of the influence of comprehensive BF redistribution in cardiovascular and hepato-gastrointestinal disease, in the postprandial period, and in relation to physical exercise. BFAb can be determined theoretically using Doppler ultrasound by subtracting BF in the bilateral proximal femoral arteries (FAs) from BF in the upper abdominal aorta (Ao) above the coeliac trunk. Prior to acceptance of this method of determining a true BFAb value, it is necessary to obtain validated normal physiological data that represent the hemodynamic relationship between the three arteries. In determining BFAb, relative reliability was acceptably high (range in intra-class correlation coefficient: 0.85-0.97) for three arterial hemodynamic parameters (blood velocity, vessel diameter, and BF) in three repeated measurements obtained over three different days. Bland-Altman analysis of the three repeated measurements revealed that day-to-day physiological variation (potentially including measurement error) was within the acceptable minimum range (95% of confidence interval), calculated as the difference in hemodynamics between two measurements. Mean BF (ml/min) was 2951 ± 767 in Ao, 316 ± 97 in left FA, 313 ± 83 in right FA, and 2323 ± 703 in BFAb, which is in agreement with a previous study that measured the sum of BF in the major part of the coeliac, mesenteric, and renal arteries. This review presents the methodological concept that underlies BFAb, and aspects of its day-to-day relative reliability in terms of the hemodynamics of the three target arteries, relationship with body surface area, respiratory effects, and potential clinical usefulness and application, in relation to data previously reported in original dedicated research.

Quantitative hemodynamic assessment of stenotic below‐the‐knee arteries using spatio‐temporal bolus tracking on 4D‐CT angiography

“…The assessed mean blood flow velocities were within the range of characteristic blood flow velocities for stenotic and non‐stenotic arteries (40–70 mm/s 46 ). Additionally, the obtained flow rates are consistent with the literature 47 …”

“…Additionally, the obtained flow rates are consistent with the literature. 47 As expected, proximal stenoses caused a decrease in mean blood flow velocity. This decrease however was not significant.…”

Time-course of thigh muscle contraction-induced blood flow magnitude in amputated lower limb with prosthesis during dynamic knee extensions: A case study

“…Any noise or interrupted blood velocity profile data was automatically omitted for calculation of the mean value. The minimum value of the coefficient of variation (<5%) for the repeated blood velocity (including individual physiological variations) measurements represented the criteria for quality control of the operator's technique (first author) at pre-exercise as well as during exercise [10][11][12][13][14]18,[24][25][26][27][28][29][30].…”

“…The probe position was stabilized (<60°) by the operator's hand throughout pre-exercise, exercise and recovery, and was precisely positioned by the first author in the center of the vessel and adjusted to cover the diameter of the vessel in the femoral artery above the bifurcation into the branches of the superficial and deep femoral arteries [10][11][12][13][14]18,[24][25][26][27][28][29][30].…”

Effects on Aortoiliac Fluid Dynamics After Endovascular Sealing of Abdominal Aneurysms

“…13 Inlet flow for CFD simulations was set to 3.5 L/min, and outlet boundary conditions at the renal arteries, the superior mesenteric artery, and the celiac trunk were set to À0.5 L/min to reproduce normal physiological values based on the literature. [14][15][16] Pressure zero references were set at each external and internal iliac outlet. These conditions were maintained across all simulations.…”