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D Pradeau

Publications and source records attributed to D Pradeau.

31 records · Page 2Linked to original sources
PubMed1987

Various techniques for the routine evaluation of the degradation of glucose in parenteral solutions--a critical study.

A practical approach is described for studying the influence of various physicochemical factors on the degradation of glucose in parenteral solutions sterilized by heating in an autoclave. Five routine analytical methods are discussed: pH determination; direct ultraviolet absorption measurement (BP) method; liquid chromatography of 5-HMF; thin-layer chromatography of sugars, carboxylic acids and carbonyl species; and enzymatic determination of glucose. The effects of various factors on the degradation of glucose were studied: glucose concentration (10%, 30%, 50%); pH of solution before sterilization (2-10); sterilization cycle (103 min at 110 degrees C, 20 min at 120 degrees C, 3 min at 134 degrees C; same Fo); time of heating at 120 degrees C (30, 40, 60 min); and the presence of salts (sodium acetate, sodium lactate, sodium chloride). The results demonstrate the importance of these factors in influencing the rate of glucose degradation during sterilization. In the presence of salts, 5-HMF is not the most important product of degradation and the BP assay is not suitable for evaluation of glucose breakdown. The authors propose two control procedures. For simple solutions of glucose, the BP method is suitable. In the presence of salts the glucose oxidase method should be used.

Journal Article↗
PubMed1987

Serum selenium deficiency in myocardial infarction and congestive cardiomyopathy.

Serum selenium concentration was prospectively measured using the method of thermoelectric atomic absorption spectrophotometry in 129 study participants distributed as follows in three groups: control group (n = 48) volunteers without known cardiac or lung disease; group I: patients with congestive cardiomyopathy (n = 48), group II: patients with myocardial infarction (n = 31). Serum selenium level was 84.73 +/- 1.79 micrograms.l-1 (m +/- sem) in the control group, 68.53 +/- 2.26 micrograms.l-1 in group I and 73.55 +/- 2.33 micrograms.l-1 in group II. The difference between group I and group II versus the control group was significant (p less than 0.01). There was no significant difference between group I and II.

Adult↗
PubMed1986

[Artificial nutrition in hospitals: general principles of quality control].

Sterile pharmaceutical preparations must be supplied to clinical wards; their high degree of safety is given by hospital pharmacists who are responsible for quality control of these preparations. Various considerations on the choice of protocol are suggested. Good manufacturing practice is to carry out quality controls at every stage of production of total parenteral nutrition fluids. However, these controls are made difficult by the poor equipment of hospital pharmacies and by the absence of specific pharmaceutical monographs. The selected protocol involves: preliminary controls, which determine the practicability of the suggested formulation, as well as its expiration date: amino acid determinations using liquid chromatography, electrolyte analysis and concentration, pH, evolution of particle size in fat emulsion according to storage conditions, choice of plastic container; microbiological controls: every two months and every time the pharmaceutical staff changes; moreover, a search for bacterial endotoxins using a chromogenic substrate (LAL technique) with "microstrips" is suggested; a sample from each admixture is kept under refrigeration for 15 days; controls during fabrication to check, at the end of the process, if good manufacturing practices have been realized: microbiological sampling of the working area and elaboration of a written procedure; control after fabrication of each nutrient admixture: determination of various elements such as sodium, potassium and dextrose in a 5 ml sample. These assays enable the checking of high standards of fabrication. Hospital pharmacies, despite their reduced equipment, can answer by these procedures to the physicians' needs and supply sterile TPN meeting pharmaceutical standards.

Electrolytes↗
PubMed1983

[Bicarbonate hemodialysis. Pharmaceutical aspects].

Specific problems during fabrication of concentrated hemodialysis solutions containing bicarbonate arise because of the low solubility of sodium bicarbonate in water and the risk or precipitation of calcium, magnesium carbonates. These problems have been solved by the Pharmacie centrale by making 2 different concentrated solutions, the first one brinding the major essential elements, at the exclusion of bicarbonate, the second less concentrated, with bicarbonate and potassium gluconate, the latter complexing iron and so preventing precipitates of ferric carbonate. The various pharmaceutical steps are described in this paper: formulation, choice of raw materials and manufacturing processes, quality control.

Bicarbonates↗
PubMedDate not supplied

Development of a standard, freeze-dried serum containing the drugs assayed most often in French hospitals.

A quality control program for the therapeutic drug monitoring methodology used to determine serum levels of the fourteen drugs assayed most frequently by French hospital laboratories is described. The program has been adopted by the Societé Française de Biologie Clinique (SFBC), which provides participating laboratories with a statistical analysis of the performance data. The control samples developed for the program are prepared by spiking calf serum with, in one case, phenobarbital, phenytoin, carbamazepine, sodium valproate, amikacin, lithium carbonate, digitoxin and hydroquinidine, and, in the other case, caffeine, quinidine, digoxin, isoniazid and gentamycin. After freeze-drying the spiked serum, the drugs were shown to be stable for at least a year when stored at -20 degrees, +4 degrees and +22 degrees; at the end of this time, the samples were pathogen free. For checking therapeutic drug monitoring methods, the freeze-dried serum is diluted with distilled water (10 ml); these solutions are chemically stable, and remain pathogen-free, when stored in stoppered glass tubes at -20 degrees or +4 degrees for 4 weeks.

Drug Contamination↗
PubMedDate not supplied

New calibration method for gas chromatographic assay of carbon monoxide in blood.

The calibration method described is based on the in situ formation of carbon monoxide in a closed system by the reaction of hot concentrated sulfuric acid with formic acid. Carbon monoxide is released from hemoglobin by treatment with 85% phosphoric acid, diluted 1:2 (v/v). Carbon monoxide is analyzed by means of headspace gas chromatography on a Porapak Q 80-100 column, following catalytic reduction to methane, using a flame-ionization detector. The method was validated by comparing the results obtained for blood samples from patients suffering from carbon monoxide poisoning and previously analyzed by means of spectrophotometry.

Calibration↗
PubMedDate not supplied

Cyanide assay: statistical comparison of a new gas chromatographic calibration method versus the classical spectrophotometric method.

This work compares two different methods for assaying hydrogen cyanide, a spectrophotometric method and a headspace gas chromatographic method, each with its own reference standard generation. In the first method, the reference standards are cyanide solutions. In the second method, the reference standards are based upon the in situ reduction of ethyl thiocyanate by dithiothreitol to produce hydrogen cyanide. Furthermore, hydrogen cyanide concentration in the blood of patients who were poisoned by smoke inhalation or who committed suicide by cyanide ingestion is determined using both methods. Results are discussed using statistical comparison.

Calibration↗