Chiba-needle percutaneous cholangiography - a method without risk to the patient?

This critical review of PTC with the skinny needle was prompted by an unexpected complication - an intrahepatic hematoma. A negative PTC does not exclude the presence of dilated bile ducts. In the case of an obstructed biliary tree, bile leakage occurs in approximately 5%. Even after the Chiba needle or other techniques have become established, peritoneoscopy is still of value in the diagnosis of cholestasis. Thus, this method is not without some risk and optimistic reports should be judged with a certain reserve.

Alternative transport pathways of cholephilic 14C-hexobarbital metabolites in rats with experimental hepatitis and cholestasis

Object of the investigation was to find out whether otherwise cholephilic metabolites are excreted via an alternative pathway into urine in experimental liver disease. Intraduodenal application of 14C-labelled hexobarbital in rats is followed by an immediate biliary excretion of metabolites in the range of 400 microgram/100 g bw/h. Using TLC these metabolites can be separated into a polar fraction (about 80% of total) and a non-polar fraction. Phenobarbital treatment leads to a decrease of the total biliary excretion of metabolites to about 200 microgram/100 g bw/h, the metabolite pattern remaining unchanged. Animals with a mild form of GalN-hepatitis had a moderate reduction of bile flow and a total metabolite output of 40 microgram/100/gbw/h. The metabolite pattern showed a decrease mainly of the polar fraction. In animals with an early stage of ANIT cholestasis a 50% reduction of bile flow was associated with a total metabolite excretion of only 20 microgram/100 g bw/h and polar metabolites were nearly absent. In both types of experimental liver disease in corresponding urine samples otherwise cholephilic metabolites appeared. The results obtained show that clinically moderate stages of experimental liver disease lead to a significantly diminished output especially of polar 14C-hexobarbital-metabolites into the bile, which can, therefore, appear in the urine instead.

The effect of dietary fiber on postprandial serum digoxin concentration in man

The postprandial digoxin concentrations in serum were measured for 4 hr by radioimmunological assay in six healthy volunteers who had received 0.8 mg beta-acetyldigoxin by the oral route. Digoxin was given together with a formula diet containing as admixture, respectively, wheat bran, microcrystalline cellulose, pectin, carrageenan, and carob seed flour. The various additions did not reduce the mean digoxin concentrations in serum. After carob seed flour, the concentrations were significantly (P less than 5%) higher, as compared to the control. After microcrystalline cellulose, pectin, and wheat bran the mean peak concentrations were reached later than in the control state.

[Methohexital clearance in patients with acute hepatitis (author's transl)]

Pharmacokinetics of methohexital were studied in patients with acute hepatitis and after a treatment period either with "essential phospholipids" or phenobarbital. During the acute phase the distribution of methohexital was significantly altered. No change had been observed in the methohexital clearance. During remission the distribution of methohexital was in a normal range. After treatment with phenobarbital the methohexital clearance increased significantly whereas no change was observed after treatment with "essential phospholipids".

[Fiberendoscopic injection therapy of bleeding gastrointestinal lesions (author's transl)]

In 28 patients with acute gastrointestinal bleeding emergency fiberendoscopy was combined with aethoxysclerole (1%) injection of the bleeding lesion with purpose to controll haemorrhage. In 61% of 31 proceudres done in patients with oesophageal varices (n = 19) haemorrhage was controlled, and in further 16% deminuation of bleeding intensity was noted. In the remaining cases (n = 7) the procedure was ineffective. Only patients with Child C liver cirrhosis having oesophageal varices stages III and IV finally died because of uncontrolled haemorrhage. In 9 patients with bleeding from other lesions (gastric erosions and ulcers, Mallory-Weiss-Syndrome, erosio simplex Dieulafoy) haemorrhage was controlled in 8 patients. The method is practicable and efficient, but does not determine better the final outcome of patients with livercirrhosis Child C having oesophageal varices stages III and IV. In other cases tube treatment was avoided. The operation lethality within the series was 1,5%.

[Studies on drug metabolism in obese men and mice (author's transl)]

In 7 obese patients with an overweight of 53 +/- 19% of Broca we found a 2-fold enlarged apparent volume of distribution and a nearly 2-fold prolonged elimination halflife of hexobarbital; the hexobarbital plasma clearance however, which is nearly identical with the metabolizing capacity of the liver for hexobarbital, was not decreased. Phenobarbital induced the microsomal drugmetabolizing enzyme system in the fatty liver of genetically obese mice in the same way 2-3-fold as in the non-fatty liver of the lean littermates.

[Percutaneous transhepatic--versus endoscopic retrograde cholangiography in the differential diagnosis of cholestasis? (author's transl)]

Since the introduction of the Chiba needle the percutaneous transhepatic cholangiography (PTC) became an established method in the differential diagnosis of cholestasis beside the endoscopic retrograde cholangiography (ERC). From the clinical point of view it is sometimes difficult to decide which of these two techniques should be preferred. In case of absolute or relative contraindications or in case of failure of one of the two methods ERC and PTC can be used alternatively. In all other cases we feel that the PTC by means of the Chiba needle is superior because of easier technical handling and higher success rate. In addition PTC is less trying for the patients. However on the basis of our own experience is should be stressed, that even by using skinny needles there is danger of bile leakage, which necessitates an immediate surgical intervention in the presence of biliary obstruction.

[Bioavailability of Ce-Ferro forte. Comparative iron load test (author's transl)]

The intraindividual relative bioavailability of three oral iron preparations was investigated in 9 male and 3 female healthy volunteers. After an overnight fast each of the volunteers took 110 mg Fe++ in a weak gelatine capsule soluble within the duodenum (Ce-Ferro forte) or 105 mg and 100 mg Fe++ respectively in commercial preparations. Care was taken that a 3 days interval took place between the investigations. Before taking and 1/2, 1, 2, 4, 6, 8 and 12 hrs. after taking the iron capsule, blood was withdrawn into heparinized test tubes and plasma iron concentrations were determined using an atomic absorption spectrophotometer. After taking Fe++ sulfate in a weak gelatine capsule (A), the mean plasma iron increased significantly higher in comparison to preparation B in the 2nd and in the 4th hour and in comparison to preparation C in the 1st hour. The area under curve of iron increase was 531 +/- 329 (SD) after A, 415 +/- 327 And 414 +/- 390 after B and C respectively without significant changes. From these data was concluded that Fe++ sulfate in a duodenal soluble weak gelatine capsule has a beter bioavailability than the 2 other preparations investigated.

Influence of corticosteroid on hexobarbital and tolbutamide disposition

The influence of 10 days' prednisone treatment on the disposition of hexobarbital and tolbutamide was studied in 7 healthy male volunteers. No significant changes in the pharmacokinetic parameters of the two drugs became apparent, which indicates that prednisone pretreatment does not affect their metabolic activities.

[Pharmacokinetics of digoxin and methyldigoxin in patients with acute hepatitis (author's transl)]

After i.v. application of 3h-digoxin or 3H-methyldigoxin to 5 healthy volunteers and 5 patients with acute hepatitis, respectively (0.75 mg daily for 3 days and 0.375 for the following 2 days) total radioactivity in urine and plasma were determined. Chloroform-soluble and -insoluble glycosides were separated and the chloroform-soluble fraction was determined by TLC. 3 days after methyldigoxin application plasma levels reached toxic values in the patient group (2.73 +/- 0.48 ng/ml), whereas in patients receiving digoxin a mean plasma level of 0.91 +/- 0.21 ng/ml was obtained. During the first 24 hours following administration of digoxin 44 +/- 12% of the dose were recovered in urine of control subjects and 48 +/- 13% in patients with acute hepatitis, after methyldigoxin 34 +/- 5% and 34 +/- 8%, respectively. Metabolism of digoxin in patients with acute hepatitis was unaltered, whereas a diminished demethylation rate of methyldigoxin could be observed. 16 patients with acute hepatitis and 7 healthy volunteers received unlabelled digoxin p.o. as maintenance dose. Plasma glycoside concentrations were studied by radioimmunoassay. The average glycoside plasma concentrations were 0.59 +/- 0.21 ng/ml and 0.63 +/- 0.24 ng/ml, respectively.

[Metabolism of hexobarbital in patients with acute hepatitis and cirrhosis (author's transl)]

16 patients with acute hepatitis, 18 patients with cirrhosis and a total of 21 volunteers and patients with normal liver function received 7.32 mg/kg hexobarbital by linear intravenous infusion within 60 min. Hexobarbital was determined gaschromatographically in serial blood samples and the hexobarbital-clearance was calculated from the plasma concentration curve versus time. Additional experiments were performed in rats suffering from so called "galactosamine hepatitis". In half of the patients with acute hepatitis a normal hexobarbital clearance could be found. In the other patients this was distinctly reduced but not correlation was found to other liver function tests. Patients with cirrhosis were subdivided into two groups. The patients in group 1 were well compensated. The patients in group 2 had a decompensated state with ascites and oesophageal varices. In nearly all patients with cirrhosis the hexobarbital-clearance was diminished. This was more pronounced in group 2. Ketohexobarbital excretion in healthy subjects was in the range of 40-60% of dose. Patients with acute hepatitis excreted only 10-20% of dose and patients with liver cirrhosis only about 5% of dose. In rats with "galactosamine hepatitis" hexobarbital clearance in vivo was distinctly reduced and this could be explained by diminished microsomal cytochrome p 45- and hexobarbital oxidation rate.

Stimulation of drug metabolism by rifampicin in patients with cirrhosis or cholestasis measured by increased hexobarbital and tolbutamide clearance

Eleven patients with hepatic cirrhosis or cholestasis were treated with rifampicin for 7 to 132 days. Ten patients received hexobarbital (7.32 mg/kg) and five received tolbutamide (20 mg/kg) by i.v. infusion prior to and after rifampicin treatment; plasma concentrations of the two test compounds were determined during and after infusion. The average elimination half-life of hexobarbital had decreased from 624 to 262 min and that of tolbutamide from 292 to 160 min following rifampicin treatment. It was calculated that the metabolic clearance of hexobarbital had increased more than two-fold and that of tolbutamide almost two-fold. The results suggests that rifampicin is able to stimulate hepatic drug metabolism in patients with liver disease. It was apparent in general that the induction did not lead to improvement of hepatocellular function during disease as judged by laboratory findings.

Influence of rifampicin on drug metabolism: differences between hexobarbital and antipyrine

Six healthy volunteers were treated with 1,200 mg of rifampicin daily for 8 days. Before and immediately afterward each received indocyanine green, hexobarbital, galactose, and antipyrine by intravenous infusion on 3 consecutive days. The plasma concentrations of the drugs were determined several times after infusion. The average elimination half-life of hexobarbital had decreased from 407 to 171 min and its metabolic clearance had increased almost threefold. In contrast, the average elimination half-life of antipyrine was virtually the same on both occasions (6.9 and 7.2 hr) and there was no change in metabolic clearance. In a tuberculous patient treated with rifampicin the antipyrine elimination rate was unaffected. Rifampicin did not influence indocyanine green clearance or galactose elimination capacity. Serum gamma glutamyl transferase was not affected but urinary D-glucaric acid excretion was increased during rifampicin treatment. The experiment with hexobarbital was repeated after 2 weeks in all subjects; half-lives and clearance values had returned to near control values. It appears that rifampicin is a selective inducer of oxidative drug metabolism in man.

Pharmacokinetic interactions with rifampicin

Rifampicin, a potent antituberculosis agent, is frequently combined with other antituberculosis drugs, or with drugs belonging to entirely different classes which may be required during a long period of antituberculous treatment, and therefore has a potential for drug interactions of practical clinical importance. The absorption of rifampicin is markedly decreased when it is simultaneously administered with para-aminosalicylic acid granules, due to adsorption by an excipient, bentonite. Several clinical observations and investigations have indicated that rifampicin itself accelerates the metabolism of various other compounds, including oral anticoagulants, the contraceptive pill, oral hypoglycaemic agents and digitoxin. Rifampicin seems to be a potent inducer of drug metabolism in humans and it causes a proliferation of the smooth endoplasmatic reticulum and an increase of cytochrome P450 content in the liver. It also increases its own rate of desacetylation. However, of the test compounds hexobarbitone and tolbutamide, the metabolic clearance increased 2-to 3-fold following rafampicin treatment, whereas antipyrine clearance was unaltered. This indicates that there is a certain selectivity in the enzyme induction effect of rifampicin, although it reamins unclear which compound will and which will not be affected. Rifampicin may also possibly interfere with hepatic uptake of other compounds, but the clinical significance of this type of interaction has not been clearly demonstrated; On the other hand, oral probenecid significantly increases the serum level of rifampicin, probably due to a similar depression of hepatic uptake.

Induction of drug metabolism in man after rifampicin treatment measured by increased hexobarbital and tolbutamide clearance

Five healthy volunteers took 1.2 g rifampicin daily for 8 days, and before and afterwards each received hexobarbital (7.32 mg/kg) and tolbutamide (20 mg/kg) by i.v. infusion on two consecutive days. The plasma concentrations of the two drugs were determined during and after infusion. The average elimination half-life of hexobarbital had decreased from 325 to 122 min and of tolbutamide from 418 to 183 min following rifampicin treatment. It was calculated that the metabolic clearance of hexobarbital had increased about three-fold and that of tolbutamide more than two-fold. Significant changes in the distribution kinetics of the two drugs were not observed. The results suggest that rifampicin is capable of inducing drug metabolism in man, which leads to an increased rate of elimination of drugs that undergo biotransformation in the liver.

Pharmacokinetics of hexobarbital in acute hepatitis and after apparent recovery

The pharmacokinetics of hexobarbital were studied in 13 patients with acute hepatitis. Hexobarbital sodium was administered by zero order intravenous (iv) infusion, and plasma concentrations were determined regularly by gas chromatography. For each patient the data were fitted according to 2-compartment kinetics. The results were compared to those obtained for 14 healthy volunteers. The elimination half-life of hexobarbital was 490 +/- 186 min in the hepatitis patients and 261 +/- 69 min in the control group. Clearance was significantly reduced in the hepatitis group, whereas the volume of distribution at steady state was not significantly altered. For some patients the initial distribution volume was reduced. In 6 patients the experiment with hexobarbital was repeated after apparent recovery from hepatitis as judged by normal transaminase and bilirubin levels. Generally the half-life of hexobarbital was shorter and the clearance value was higher than during the acute illness, but the values had not yet returned to normal. Clinical recovery from liver disease is not accompanied by corresponding recovery of drug-metabolizing capability.

[Cholestatic jaundice after taking the laxative Normolaxol]

Report on two cases of jaundice developing shortly after ingestion of a new laxative, Normolaxol (quinolylmethylenediphenol). Clinical and morphological aspects of the acute cholestasis are described and discussed regarding differential diagnosis and pathogenesis.

Pharmacokinetics and metabolism of digoxin- and beta-methyl-digoxin-12aplha-3 H in patients with acute hepatitis

Pharmocokinetics and metabolism of digoxin and beta-methyldigoxin have been studied in patients with acute hepatits after intravenous administration of both H-labeled glycosides. In contrast to digoxin, the rate of decline of radioactivity after administration of beta-methyldigoxin was significantly retarded in patients with acute hepatitis. The increase in plasma concentration after beta-methyldigoxin to patients with acute hepatitis is probably related to decreased demethylation.

Pharmocokinetics of hexobarbital in man after intravenous infusion

The plasma levels of hexobarbital in humans were determined during and after a 30-min or 60-min zero-order intravenous infusion. Hexobarbital kinetics could be described by conceiving the body to exhibit two compartments. The plasma concentrations were fitted to the postinfusion equation and the parameters intrinsic to the two-compartment open model were estimated. The elimination half-life varied considerably among the 14 individuals (160-441-min), which could mainly be explained by the greatly varying metabolic clearance of the compound (123-360 ml/min). The apparent volume of distribution per kilogram of body weight was relatively constant (1.10 plus or minus 0.12 liters/kg).