Hepatic arterial doppler sonography in patients with cirrhosis and controls: observer and equipment variability with use of the ultrasonic contrast agent SHU 508A.

PURPOSE: The aims of this study on hepatic arterial Doppler sonography were to ascertain interobserver and interequipment variability, to investigate any potential artificial influence of the ultrasonic contrast agent on the Doppler measurements and to compare the results in healthy and cirrhotic subjects. METHODS: Doppler sonography of the left hepatic artery was performed in nine healthy and nine cirrhotic subjects by three independent observers using three different devices. Continuous infusion of the ultrasonic contrast agent SHU 508A and placebo were administered in a double blind fashion. Systolic, mean and end diastolic peak velocities as well as resistive and pulsatility indices were measured. RESULTS: Equipment associated variances (5.8 - 12.7 %) of the five Doppler parameters were greater than interobserver variances (0.3 - 3.6 %). No significant differences were observed between the velocities using ultrasonic contrast agent and placebo. Systolic (65.9 +/- 3.6 vs. 47.7 +/- 4.2 cm/s mean +/- SE, p = 0.02) and mean peak velocity (35.4 +/- 1.6 vs. 24.5 +/- 1.8 cm/s, p = 0.007) were significantly higher in cirrhotic than in healthy subjects whereas the resistive and pulsatility indices were not different. CONCLUSIONS: Doppler sonography of the left hepatic artery performed by various observers is reproducible as long as the same device is used. Under clinical conditions, velocities are correctly measured with the use of ultrasonic contrast agent and are elevated in patients with cirrhosis.

Hepatic arterial blood flow velocities: assessment by transcutaneous and intravascular Doppler sonography.

BACKGROUND/AIMS: Doppler sonography has been used to assess hepatic arterial perfusion in a number of published reports. However, adequate validation studies are available for neither the transcutaneous nor the intravascular Doppler approach. The aim of this comparative study was to assess hepatic arterial perfusion with both methods. METHODS: In 15 patients the right hepatic artery was examined with intravascular and transcutaneous Doppler sonography after calibration of Doppler devices in vitro with a thread model. The measurements were performed simultaneously in five and separately within 24 h in 10 patients. RESULTS: In vitro, the correlations between the velocities of the thread and the velocities as determined by intravascular (r=1.0, p<0.001) and transcutaneous Doppler sonography (r=1.0, p<0.001) were excellent. In vivo, the best correlation was found for systolic peak velocities (intravascular: 58.5+/-18.1 cm/s, mean+/-standard deviation, transcutaneous: 58.2+/-25.2 cm/s, r=0.63, p=0.01). Although lower mean (intravascular: 26.5+/-7.7 cm/s, transcutaneous: 32.5+/-14.4 cm/s) and end-diastolic velocities (intravascular: 11.5+/-4.0 cm/s, transcutaneous: 18.4+/-8.6 cm/s) were found with intravascular compared to transcutaneous Doppler sonography, significant correlations were demonstrable between results obtained by both methods (r=0.63, p=0.01 for mean and r=0.57, p=0.025 for diastolic velocities). Similarly, the calculated resistive (intravascular: 0.79+/-0.07, transcutaneous: 0.68+/-0.06, r=0.65, p=0.009) and pulsatility indices (intravascular: 1.78+/-0.47, transcutaneous: 1.26+/-0.25, r=0.55, p=0.034) were somewhat higher using the intravascular device, but correlated well with the numbers obtained by the transcutaneous approach. CONCLUSIONS: The data suggest that with use of different Doppler devices, systolic velocities are the most suitable parameter for Doppler assessment of hepatic arterial perfusion.

[Surgical therapy of chronic visceral arterial ischemia with aortoceliac, mesenteric patch bypass]. / Chirurgische Therapie der komplexen chronischen Visceralarterienischämie mit aortocoeliacalem, mesenterialem Patch-Bypass.

Based on two patients suffering from chronic visceral ischemia, the anatomic and pathophysiologic principles prior to surgery are discussed. Antegrade revascularization is supposed to be better hemodynamically. Complete revascularization of multiple arteries seems to be theoretically superior to one-vessel procedures. Within the bypass procedures the aortic-celiac-mesenteric patch bypass could be an excellent surgical possibility combining antegrade with simultaneous revascularization of celiac and superior mesenteric artery.

Effects of cardiac output on disposition kinetics of sorbitol: recirculatory modelling.

1. The purpose of this study was to determine the effects of cardiac output on distribution and elimination kinetics of the marker compound sorbitol. 2. The disposition kinetics of sorbitol were investigated after rapid intravenous injection and arterial sampling in nine patients who had undergone cardiac catheterization whereby the cardiac output was measured. 3. A minimal circulatory model consisting of pulmonary and systemic subsystems, both of which were characterized by an inverse Gaussian transit time density function, fitted the data very well. The method involves numerical inverse Laplace transform of the model equations. 4. The mixing clearance introduced as a novel non-compartmental parameter of distribution dynamics was significantly correlated with cardiac output. The steady-state volume of 14 l matched the extracellular volume. The systemic extraction ratio of 23% may reflect the fractional liver blood flow. 5. This pharmacokinetic model can be applied when an independent observation of cardiac output is available. In contrast to the conventional compartmental (or sum of exponential) approach it contains fewer adjustable parameters which can be more readily interpreted in physiological terms.

[Media sclerosis: a case of pseudohypertension]. / Mediasklerose: Ein Fall von Pseudohypertonie.

A 51-year-old diabetic showed symptoms of a hypertensive crisis with a systolic blood pressure above 300 mmHg. The antihypertensive therapy failed and the Doppler-pressure values were also too high for all limb arteries. Duplex-sonography and soft-x-ray examination showed a mediasclerosis of arms and legs. The true pressure, measured at the still compressable arteries of the fingers was relatively low. There was symptomatic improvement after completion of the antihypertensive therapy.