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Stability of all-in-one standard formulae for paediatric parenteral nutrition.

The Robert Debré Hospital pharmacy unit ensures an annual manufacturing rate of 20,000 parenteral nutrition bags. Until 1999, these bags consisted in binary admixtures, fat emulsions being administered to the patient via a "Y" connexion on the catheter. Since then, all-in-one standard formulae have been established and are manufactured using a Baxa MM23 automated compounder. The aim of this study was to assess the physico-chemical stability of all-in-one admixtures, in order to ensure patient administration safety (mainly avoiding precipitation risks between the nutrients). Three bags of each standard formula were manufactured in monocompartmental bags. Stability assays consisted in the assessment of the admixture's (1) macroscopic aspect, (2) drop size measurement, (3) zeta potential measurement, (4) pH measurement, and (5) osmolality measurement. Tests were conducted between D0 (manufacturing day) and D10 (10 days after manufacture). All-in-one admixtures manufactured according to the established standard formulae were found to be stable for at least 10 days, provided they are kept away from light and at a temperature of +4 degrees C.

Amino Acids↗

Stability and compatibility of methylprednisolone sodium succinate and cimetidine hydrochloride in 5% dextrose injection.

The stability and compatibility of methylprednisolone sodium succinate in admixtures with cimetidine hydrochloride in 5% dextrose injection were determined. Admixtures containing methylprednisolone sodium succinate, in concentrations equivalent to methylprednisolone 0.4 or 1.25 mg/mL, and cimetidine 3 mg/mL (as the hydrochloride salt) were prepared in 5% dextrose injection 100 mL. Control solutions containing each drug alone at the same concentrations were also prepared. The admixtures were prepared in triplicate and were kept in polyvinyl chloride infusion containers at controlled room temperature (24 degrees C). Immediately after mixing and at 2, 4, 8, 12, and 24 hours, samples were removed and visually inspected, measured for pH, and assayed by stability-indicating high-performance liquid chromatography to determine the concentrations of methylprednisolone 21-succinate ester and cimetidine. No visual evidence of incompatibility was noted either with the unaided eye or a microscope. No substantial changes in pH occurred over the study period. The addition of cimetidine decreased the pH of the methylprednisolone sodium succinate control solutions from about 7.3 to about 5.6. The concentrations of methylprednisolone 21-succinate ester and cimetidine in both test and control solutions did not change significantly over the 24-hour study period. Methylprednisolone sodium succinate, in concentrations equivalent to methylprednisolone 0.4 and 1.25 mg/mL, was chemically stable and visually compatible in admixtures with cimetidine 3 mg/mL (as the hydrochloride salt) in 5% dextrose injection 100 mL at 24 degrees C for 24 hours.

Cimetidine↗

Stability of miconazole in peritoneal dialysis fluid.

The stability of miconazole when mixed with peritoneal dialysis (PD) fluid and stored in plastic bags or glass ampuls was determined. Admixtures of miconazole and PD fluid were prepared in 2-L polyvinyl chloride (PVC) bags and in 1-mL glass ampuls to give a nominal initial concentration of 20 mg/mL. Duplicate samples of each solution were assayed in duplicate by high-performance liquid chromatography immediately after preparation and at various intervals up to nine days. All admixtures were stored in ambient light at 20 +/- 2 degrees C. A substantial loss of miconazole (greater than 10% of the initial concentration) occurred within four hours for admixtures stored in PVC bags, whereas similar solutions retained more than 90% of their initial miconazole concentration for at least three days when stored in glass ampuls under the same conditions. This suggests that the observed loss of miconazole from the PVC bags was largely due to an interaction with the container, rather than to chemical degradation in solution. About 28% of the miconazole lost from the solution during storage in PVC bags was recovered from the plastic by methanolic extraction. The rapid loss of miconazole when the drug was mixed with PD fluid and stored in PVC bags indicates that such admixtures should be prepared immediately before administration.

Chromatography, High Pressure Liquid↗

Stability of cotrimoxazole in peritoneal dialysis fluid.

This study examines the stability of both components of the antibacterial combination, cotrimoxazole (trimethoprim and sulphamethoxazole) in peritoneal dialysis fluid stored in polyvinyl chloride bags and glass ampoules at room temperature for up to nine days. Greater than 10% loss of trimethoprim occurred within three days for admixtures stored in plastic bags, whereas the original concentration remained virtually unchanged after nine days for similar solutions stored in glass ampoules. This indicated that the loss of trimethoprim observed in solutions stored in plastic bags was associated primarily with the nature of the container, presumably due to some form of uptake by or loss through the plastic. Greater than 10% loss of sulphamethoxazole occurred within two days for all admixtures examined, stored in either glass or plastic containers. This degree of loss was achieved within 12 h for one admixture stored in plastic. There was also the time-dependent appearance of an additional peak in HPLC analyses of these solutions, indicating that loss of sulphamethoxazole was due to chemical decomposition of the drug in the peritoneal dialysis fluid. The shelf-life of such admixtures would be limited by the stability of the sulphamethoxazole component, with the available data suggesting a shelf-life of 12 h for solutions stored at room temperature.

Chromatography, High Pressure Liquid↗

[Disorders of the oxygenating function of the lungs during open-heart surgery].

A retrospective analysis of arterial blood oxygenation during open-heart surgery in 463 patients revealed pulmonary oxygenation disorders in 23% prior to perfusion and in 49% in the post-perfusion period. The basic mechanism underlying the fall in arterial blood oxygenation is the increasing venous admixture in the lungs. A growth in the venous admixture in the post-perfusion period is brought about by a decreased total ventilation/perfusion ratio, increased alveolar shunting, and impaired diffusion. It was found, that the assisted ventilation regimen at +5+8 cm H2O in the post-perfusion period caused a 30% reduction in the venous admixture and improved the blood oxygenation. Additional use of diuretics to diminish the intrapulmonary water causes a 59% reduction in the venous admixture. A prophylactic pre-perfusion administration of corticosteroids, vitamin E, and protease inhibitors maintains the oxygenating function of the lungs, which is manifested in a higher blood oxygenation in these patients after assisted circulation compared to the controls.

Adrenal Cortex Hormones↗

Ethnicity determination by names among the Aymara of Chile and Bolivia.

The importance of surnames in genetic studies has been recognized for a century or so. While the ethnic affiliations of individuals are ordinarily established in genetic studies by admixture analysis based on gene frequencies, often there are implicit assumptions in these attempts that are difficult to validate in the absence of detailed ethnohistories. In northern Chile and western Bolivia, where genetic admixture has been known to occur among the Aymara Indians and Spanish Caucasoids, the naming pattern (parental patriand matrinyms) allowed us to classify individuals on the basis of the frequency of Aymara names into 9 'ethnic' groups. From a sample of 2525 individuals it is shown that admixture occurred in lineages nonrandomly, implying assortative mating of surnames. Admixture and genetic distance analysis on the basis of 31 genetic markers on approximately 1700 of these individuals reveals that there is a reasonable agreement of ethnic classification of individuals by name and phenotype data on genetic markers. The Aymara-named groups are shown to be predominantly Amerindian (89%) in their genetic profiles. Individuals whose current naming pattern is basically Spanish also exhibit a substantial fraction of genes of Amerindian origin (67%). Presence of some rare alleles not found in Amerindian or Spanish Caucasoids in the admixed groups suggest infiltration of Negroid genes in the past.

Bolivia↗

Compatibility of esmolol hydrochloride with morphine sulfate and fentanyl citrate during simulated Y-site administration.

The compatibility and stability of esmolol hydrochloride in admixtures during simulated Y-site injection of morphine sulfate or fentanyl citrate was studied. One milliliter of either morphine sulfate (15 mg/mL) or fentanyl citrate (0.05 mg/mL) was injected into a running infusion of esmolol hydrochloride (10 mg/mL) in 5% dextrose and 0.9% sodium chloride injection, and the solution was visually observed for changes. To determine the stability of the drugs during Y-site injection, esmolol hydrochloride 4 mL (1000 mg) in 5% dextrose and 0.9% sodium chloride injection was combined with 100 mL of either morphine sulfate 15 mg/mL or fentanyl citrate 0.05 mg/mL to simulate concentrations of the drugs that might be expected during Y-site injection. The admixtures were stored at ambient room temperature under normal light, and drug concentrations were determined using high-performance liquid chromatography at time zero and at two, four, and eight hours. Admixtures were also tested for pH and observed for visual changes. No immediate changes were observed in any of the admixtures, and the concentrations of the drugs varied by less than 4% throughout the study period. No precipitate or color changes were noted during Y-site injection of either drug into the running esmolol infusion. Under all of the conditions studied, esmolol hydrochloride in 5% dextrose and 0.9% sodium chloride injection is compatible with morphine sulfate or fentanyl citrate.

Adrenergic beta-Antagonists↗

Stability of cisplatin, iproplatin, carboplatin, and tetraplatin in commonly used intravenous solutions.

The stability of cisplatin, iproplatin, carboplatin, and tetraplatin in common intravenous solutions was studied. Admixtures of each drug in each of the following vehicles were prepared in glass containers: 0.9% sodium chloride injection, 5% dextrose injection, 5% dextrose and 0.9% sodium chloride injection, 5% dextrose and 0.45% sodium chloride injection (admixtures were prepared in plastic bags also), and 5% dextrose and 0.225% sodium chloride injection. Drug concentrations were monitored for 24 hours using stability-indicating high-performance liquid chromatographic methods. The stability of cisplatin and tetraplatin was related to the chloride ion content of the infusion fluid; when the infusion fluid contained 0.9% sodium chloride, each of these drugs was present at greater than 90% of the original concentration after six hours. The stability of iproplatin was not related to chloride concentration. A slight increase in the decomposition rate of carboplatin was observed in the presence of chloride ion. Carboplatin and iproplatin are stable for 24 hours in all the infusion fluids studied, but carboplatin should not be diluted with solutions containing chloride ions because of possible conversion to cisplatin. Cisplatin is stable for 24 hours in admixtures containing sodium chloride concentrations of 0.3% or greater. Tetraplatin is stable for six hours in admixtures containing sodium chloride concentrations of at least 0.018%.

Antineoplastic Agents↗

Stability of aqueous solutions of amoxicillin sodium in the frozen and liquid states.

The stability of aqueous admixtures of amoxicillin sodium in both the liquid and frozen (solid) states was studied. Admixtures of amoxicillin sodium were prepared in sterile water for injection to a theoretical concentration of 10 mg/mL. For each experimental run, 2-mL aliquots of the admixture were placed in stoppered glass volumetric flasks and stored at temperatures ranging from 19.5 degrees C to -30 degrees C; 16 flasks were stored at each temperature. After equilibration for approximately 20 minutes, duplicate flasks at each temperature were removed from storage conditions for time-zero assay. Subsequently, duplicate flasks were assayed at various times, depending on the storage temperature, for up to 13 days or until more than 80% of the drug had degraded. All samples were assayed at least in duplicate using high-performance liquid chromatography. When amoxicillin solutions were in the liquid state (at temperatures between 19.5 and 0 degrees C), the time required for the amoxicillin concentration to decrease to 90% of its initial value (t90) increased as temperature decreased. However, between 0 degree C and -7 degrees C, the t90 of frozen solutions decreased from two days to 1.08 hours. As temperature declined further, the rate of degradation decreased until the solution was completely frozen; at -30 degrees C, the t90 had increased to 13 days. Amoxicillin sodium is unstable in aqueous solutions stored between 0 degrees C and -20 degrees C. If admixtures of this drug are to be frozen for later use, the storage temperature should be below -30 degrees C.

Amoxicillin↗

Compatibility of heparin sodium and morphine sulfate.

The compatibility of morphine sulfate and heparin sodium was studied in solutions of deionized water and 0.9% sodium chloride. Crystalline morphine sulfate was reconstituted and heparin sodium 100 or 200 units/mL was added. Duplicate samples with a final volume of 5 mL were prepared and stored at room temperature. Morphine sulfate concentrations were 1, 2, 5, and 10 mg/mL in each diluent with each heparin concentration. Samples were visually inspected immediately after preparation and at 0.5 and 24 hours; pH was tested before adding heparin and at 0.5 and 24 hours. Similar procedures were followed adding morphine to the heparin. Samples containing morphine sulfate 2 and 10 mg/mL were analyzed by high-performance liquid chromatography for morphine concentrations immediately before adding heparin and at 0.5 and 24 hours. Precipitate appeared immediately after the second drug was added in samples containing morphine sulfate 10 mg/mL at both heparin concentrations in the water admixtures. No precipitate formed in any solutions containing morphine concentrations of 5 mg/mL or less nor in any samples containing 0.9% sodium chloride. In both diluents, pH values decreased as morphine sulfate concentrations increased. Morphine sulfate concentrations decreased significantly in water admixtures but not in admixtures prepared with 0.9% sodium chloride solution. Morphine sulfate and heparin sodium are incompatible only at morphine concentrations greater than 5 mg/mL. The incompatibility can be prevented by using 0.9% sodium chloride as the admixture diluent.

Chemistry, Pharmaceutical↗

Sorption of amiodarone to polyvinyl chloride infusion bags and administration sets.

The loss of amiodarone from i.v. admixtures to flexible polyvinyl chloride (PVC) infusion bags and i.v. administration sets was studied. Admixtures containing amiodarone hydrochloride 600 micrograms/mL and either 5% dextrose injection or 0.9% sodium chloride injection were stored at room temperature in glass bottles (both with and without contact of the drug solution with the rubber bottle closure), in flexible PVC bags, or in rigid PVC bottles. After 120 hours, the contents of each flexible PVC bag were emptied and replaced by methanol, which was allowed to remain in the bag for an additional 120 hours and was then analyzed for amiodarone content. To determine availability of amiodarone after infusion through a 1.8-m PVC i.v. administration set, solutions stored in glass containers were run through the set at 0.5 mL/min for 90 minutes. Samples of drug solutions were collected at appropriate intervals and analyzed by a stability-indicating high-performance liquid chromatography (HPLC) assay. Admixtures containing 0.9% sodium chloride injection were not stable; visual incompatibility was evident after 24 hours of storage in glass bottles, and no further testing was performed. In admixtures containing 5% dextrose injection that were stored in 50-mL flexible PVC bags, 60% of the initial amiodarone concentration remained after 120 hours; approximately half of the lost drug was recovered with the methanol. In effluent collected from the PVC administration set, 82% of the initial amiodarone concentration remained. Amiodarone concentrations did not decrease appreciably, after storage in glass or rigid PVC bottles, indicating that drug loss was probably affected by the plasticizer, di-2-ethylhexyl phthalate.(ABSTRACT TRUNCATED AT 250 WORDS)

Adsorption↗

[Bichromate oxidizability as a measure of the quantitative amount of organic impurities in regenerated water].

Experiments have been carried out to study permanganate and bichromate oxidation of chemicals that may contaminate reclained water, initial and intermediate products of reclamation. Permanganate oxidability can be used as a qualitative indicator of water contamination with readily oxidizable admixtures only. Bichromate oxidability can be employed as a quantitative indicator of the total content of organic admixtures, provided that oxidation is carried out in a certain way. For the water reclaimed from the atmospheric condensate the following correlation between bichromate oxidability and the concentration of admixtures has been established: 1 mg O2 consumed corresponds approximately to 0.66 mg of organic admixtures in water.

Chemical Phenomena↗

Liquid chromatographic and ultraviolet spectrophotometric determination of bevantolol and hydrochlorothiazide in feeds.

Separate assay methods have been developed for the 2 components of an 80 + 20 drug blend of bevantolol and hydrochlorothiazide (HCT) in admixtures with animal feed. Drug/diet admixtures are extracted with methanol for reverse phase ion-pair liquid chromatographic (LC) assay of bevantolol, and with acetonitrile for ultraviolet spectrophotometric assay of HCT. Bevantolol, a cardioselective beta blocker, is separated from soluble feed components with an RP-18 column, using methanol-water-acetic acid (60 + 40 + 1) containing 0. 005M octane-sulfonic acid, sodium salt, as ion-pairing reagent. HCT is determined spectrophotometrically in acetonitrile extracts, using a suitable blank extract as reference. Average recovery of HCT from an admixture of 0.5 mg blend/g diet is 94.5% +/- 4.3 RSD and at 2.0 mg/g, 101.5% +/- 3.5 RSD. Bevantolol recovery from the same admixtures is 101.8% +/- 2.7 RSD and 99.0% +/- 3.5 RSD, respectively, using the method as described.

Adrenergic beta-Antagonists↗

Justification and operation of a critical-care satellite pharmacy.

Development and implementation of a pharmacy satellite for critical-care areas in a 700-bed community hospital are described. Before the satellite, central-pharmacy personnel filled 70% of critical-care orders; the remainder of medications were floor stock. Large-volume admixtures were prepared by nurses on the critical-care units. In planning for a satellite pharmacy, turn-around time and lost drug charges were studied. Workload and staffing projections and potential expenses and revenues associated with the proposed satellite were presented to the hospital administration. The satellite was approved and serves 82 beds including the critical-care areas. It is open 16.5 hours/day and provides all i.v. admixtures. Drug distribution is computerized, and pharmacists participate on the CPR team and on physician rounds. Data collected four months after the satellite opened showed shorter turnaround time, decreased floor stock inventory, fewer lost charges, and additional revenue from preparation of i.v. admixtures. Ten months after the satellite was opened, a unit dose system was implemented. Through implementation of the satellite, shorter turnaround time for medication orders and i.v. admixtures, improved drug control, and greater control over billing were achieved.

Hospital Bed Capacity, 500 and over↗

Factors affecting the availability of diazepam stored in plastic bags and administered through intravenous sets.

Factors affecting the loss of diazepam from i.v. admixtures to flexible polyvinyl chloride (PVC) bags and to various administration sets were studied. Admixtures containing diazepam and 0.9% sodium chloride injection were stored for up to 550 hours in flexible PVC bags and in glass vials at various temperatures. Diazepam injection containing two different solvents was used. Initial diazepam concentrations in storage studies ranged from 25 to 100 micrograms/ml and pH ranged from 4.2 to 7.5. To determine availability of diazepam after infusion through administration sets, solutions (50 micrograms/ml) from glass containers were run through six different sets at 1 ml/min for seven hours. In storage studies, the difference in composition of the solvent was found to have only a slight effect on the rate and extent of diazepam loss. Diazepam loss was unaffected by pH. For admixtures stored in 1000-ml flexible PVC bags, the fractional loss of diazepam was greater at small volumes. The diazepam concentration of solutions in flexible PVC bags decreased more rapidly during infusion than during storage of the total original volume. The fraction of diazepam remaining in stored solutions was independent of the initial concentration, but the rate and extent of diazepam loss was greater at higher temperatures. Diazepam loss was dependent on length of flexible PVC tubing, and diazepam availability was greater with faster flow rates. In solutions infused through the polyolefin Tridilset, 100% of the diazepam remained. When storage of diazepam admixtures in PVC bags or administration through PVC tubing cannot be avoided, measures to minimize the rate and extent of diazepam loss include decreasing the temperature and the storage time and increasing the surface-area-to-volume ratio and the flow rate. Equations are presented for calculating the amount of diazepam delivered.

Adsorption↗

["All in one" parenteral nutrition: is it that safe?].

The use of "all in one" admixtures is supported by an extensive number of studies and by many years of experience. However, we detected stability problems in some mixtures whose stability was previously reported. We made modifications in one of these mixtures [composed of 1.000 ml Freamine 8.5%, 100 ml 10% dextrose, 500 ml water, 500 ml Intralipid 20%, 75 ml electrolyte solution (Na 75 mEq, K 60 mEq, Ca 15 mEg, Mg 15 mEq, Cl 90 mEq, acetate 75 mEq)] in order to see how the different components affect the emulsion stability. All the admixtures were visually inspected after storage during 24 hour at room temperature. It was observed that admixtures with low glucose concentration, high electrolyte levels and high volume were less stable than admixtures containing high glucose, low electrolyte and low volume. Amino acid concentration did not increased the stability as expected. MCT/LCT emulsions were more stable than LCT emulsions. More studies are needed to explain the stability problems of these TPN solutions.

Amino Acids↗

[Method of the spectrophotometric analysis of polyene antibiotics].

The method of quantitative spectrophotometric analysis of several substances in the presence of admixtures is described. The method is based on presentation of an unknown spectrum of the admixture absorption by the polyen of the 3rd or 4th power depending on the wave length. The optical density of the mixture of any wave length is expressed by the linear equation, including the Firord equation for the known components and the given polynome. The system of such equations for 10-15 analytical wave lengths may be solved with the method of the least squares using an electronic computer. The system solvations are the concentrations of the mixture components to be determined and the polynome coefficients. The method was tested on model mixtures composed of amphotercin B, myocheptin, nystatin and griseofulvin, as well as of isomeric nitroanilines playing the role of the admixture. The analysis error for the compounds of the polyenic structure having not less than 2 absorption maxima in the given spectral ranges did not exceed 1-3 per cent. As for the compounds with a single maximum or when the admixture included also polyenic compounds the analysis error increased up to 6--50 per cent.

Amphotericin B↗

Chemical compatibility of cefmetazole sodium with ranitidine hydrochloride during simulated Y-site administration.

The stability of cefmetazole sodium and ranitidine hydrochloride was studied under conditions simulating administration via a Y-injection site into a primary infusion line. Cefmetazole sodium was reconstituted with both 0.9% sodium chloride injection (50 mL or 100 mL) and 5% dextrose injection (50 mL) to produce premixing concentrations of cefmetazole 10 and 20 mg/mL. Ranitidine hydrochloride injection was diluted with 50 mL 0.9% sodium chloride injection to give premixing concentrations of ranitidine 1 mg/mL. To simulate Y-site administration, 2 mL of cefmetazole was mixed with 2 mL of ranitidine in a 10-mL glass test tube. All study mixtures were prepared in triplicate and stored at room temperature (22-23 degrees C) under normal fluorescent room lighting. Samples of these admixtures were inspected for visual changes and tested for pH. The concentrations of two drugs were immediately determined by stability-indicating high-performance liquid chromatographic assay methods after mixing and at 1, 2, and 4 hours. No visual changes were observed. The pH in the admixtures was influenced by concentrations of the two drugs. The pH of each single-drug solution did not change during the study period. On the other hand, the pH of any admixtures of cefmetazole and ranitidine solutions prepared with 0.9% sodium chloride or 5% dextrose injection, decreased. Cefmetazole in any of the admixtures with ranitidine retained greater than 95% of its original concentration for 4 hours.(ABSTRACT TRUNCATED AT 250 WORDS)

Cefmetazole↗