Blutalkohol 2005 - BADS (Bund gegen Alkohol und Drogen im ...

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Breitmeier/Verner/Albrecht/Fieguth/Geerlings/Kleemann/Panning/Gebel/Tröger,
Arteriovenous differences (A-V differences) by patients with a hepatocellular carcinoma
in relation to percutaneous ethanol injection therapy (PEIT)
Discussion
In 1940/41 HAGGARD et.al [27, 28] published data about alcohol absorption, distribution
and elimination in animals and pointed out A-V differences. In 1969 GOSTOMZYK et al. [29]
researched the phenomenon of A-V differences. CHIOU [30,31] stated that it can be of importance
for the analysis of blood samples in toxicology as well as in clinical pharmaceutical
kinetics from which blood compartment the sample was taken. He demanded further
search to clarify A-V differences. A very detailed description of A-V differences between
arterial and venous blood after oral intake in humans as well as alcohol concentration in
breath can be found at MARTIN et al [21].
In contrast to other studies [20, 21, 32, 33] in which healthy and predominantly male volunteers
were given alcohol orally or intravenously, we examined hospitalized patients with
a hepatocellular carcinoma within PEIT. The injected alcohol affects the tumor directly and
toxically, in addition an obstruction of tumor vessels through alcohol bubbles can be observed.
As a result the tumor becomes necrotic. When injecting alcohol it can happen that
the tumor is not hit directly but liver veins are punctuated, as a result of which the alcohol
can spread directly into the system. In addition alcohol can be set free through venous
tumor vessels so that alcohol can spread within the system. It is impossible to determine
when and which amount of alcohol is released by the tumor. In order not only to measure
BAC in the arterial and peripheral venous tumor vessels, we inserted a catheter using ECG
monitoring into the superior vena cava to determine BAC in the central venous vascular
system. The tip of the catheter was positioned in front of the right ventricle to minimize
interferences from mixing.
This study clearly shows that the principle of the typical tri-phasic distribution pattern
that has previously been shown in animals and in healthy volunteers after oral or intravenous
injection [20, 21, 32, 33], is confirmed by the kinetics of distribution following
ethanol injection directly into the liver tumor without any ethanol loss due to resorption
deficits or hepatic metabolisms parallels. In addition, our study in these selected patients
confirms previous results [21, 30, 31] obtained in healthy adults that ethanol concentration
in the arterial blood is higher than in peripheral venous blood during the resorption phase
until maximum ethanol concentration in these compartments was reached.
We have detected arterial peak ethanol levels of 1.47 g/kg that may be quickly reached
following injection into the tumor and are being released from the venous tumor vessels
into the liver veins. After passage of the right atrium and ventricle and pulmonary circulation,
the ethanol distribution during the period of rapidly increasing absorption apparently
occurs mainly via the arterial circulation, as is revealed by higher ethanol levels in the
arterial blood samples. It seems likely that the route of administration of alcohol is also
important to consider the A-V differences during the absorption and elimination period.
A-V differences can be expected whenever the rate of absorption occurs faster than the rate
of equilibration between blood and all other body fluids and tissues [20]. Since solubility
in lipids of ethanol is low and because of the fact that ethanol does not bind to plasma proteins,
ethanol will be transported only by the bloodstream to all parts of the body, so volume
of distribution is closely related to the amount of body water [19]. Therefore the
ethanol equilibration is dependent on the ratio of blood flow to tissue mass.
Taking into account the bloodflow one can conclude that alcohol spreads first through
the arterial system in the body. Once alcohol has passed the organic system or the capillary
BLUTALKOHOL VOL. 42/2005