Admixtures compatibility

Admixture compatibility- Digoxin injection can be administered undiluted or diluted with a 4-fold or greater volume of sterile water for injection, 0.9% sodium chloride injection, or 5% dextrose injection. The use of less than 4-fold volume of diluent could lead to precipitation of the digoxin. Immediate use of the diluted product is recommended. 

Admixture compatibility/incompatibility Intermittent IV infusion with a Y-type administration set can be accomplished with compatible solutions however, during infusion of a solution containing cefepime, it is desirable to discontinue the other solution. 

Two factors affect the reaction of both the wet and dry processes, viz. (1) mix design and (2) the ambient conditions prevailing during the spraying of the concrete. Mix design factors include cement type and content, water- cement ratio, cement-admixture compatibility and the presence of other admixtures. Cements with higher C3A contents such as Types I and III give faster reactions than cement with low C3A contents such as Types IV... 

The determination which cement properties are controlling cement-admixture compatibility is of the key importance in resolving this problem. Therefore many studies dealing with this question have been carried out recently [385-393]. 

Hanehara and Yamada [360] studied the effect of PA admixture addition on the flow diameter and found an exact lelationship in the case of w/c = 0.4 however the results are not always good for w/c = 0.3 because of the effect of cement with water mixing procedure. This problem was resolved by addition of limestone powder. According to these authors there is no general method of cement-admixture compatibility establishment, but it is possible to settlement certain experimental conditions, which permit to determine it. It is moderate fineness of cement and suitable w/c. Moreover, the proper conformity criteria should be selected, because the plastic viscosity, yield stress value and flow diameter can give various results [400]. In Fig. 6.105 the effect of SP on the relative flow area, chosen as cement-SP compatibility determining parameter, after Yamada [400] is shown. SP does not affect the relative flow area below the threshold value, above this value the flow area is increasing proportionally with admixture, but above the saturation level this parameter is not influenced by an admixture content. 

Another concern is the coinfusion of intravenous medications with PN admixtures. Many intravenous medications have limited compatibility with 3-in-l formulations but may be coinfused with a 2-and-l formulation.23,24 Some medications can be coinfused at the Y-site, few medications can be mixed directly into the PN solution or coinfused with intravenous lipid emulsion, and some cannot be mixed or coinfused with the PN admixture.23,24 Always consult compatibility data before adding a medication to a PN admixture or coinfusing with PN. Medications that are compatible should be added to PN only if it is reasonable and safe (i.e., based on toxicity profile, pharma-cokinetic/pharmacodynamic considerations). 

Where the instructions for use of the product involve admixture or dilution with drinks or other materials, appropriate compatibility data will be required. Factors to consider include ease and rate of dissolution, homogeneity, chemical and physical stability over the period of use, particle size, etc. 

Typical compositions of polymeric GMs are depicted in Table 26.3. As the table shows, the membranes contain various admixtures such as oils and fillers that are added to aid the manufacturing of the FML but may affect future performance. In addition, many polymer FMLs will cure once installed, and the strength and elongation characteristics of certain FMLs will change with time. It is important therefore to select polymers for FML construction with care. Chemical compatibility, manufacturing considerations, stress-strain characteristics, survivability, and permeability are some of the key issues that must be considered. 

Appropriate resources should be consulted for compatibility and stability information before mixing components (e.g., manufacturer s information, Trissel s Handbook on Injectable Drugs, and King Guide to Parenteral Admixtures). 

Admixture incompatibilities - Avoid adding sodium bicarbonate to parenteral solutions containing calcium, except where compatibility is established precipitation or haze may result. Norepinephrine, dopamine, and dobutamine are incompatible. 

Admixture incompatibility The compatibility of sodium ferric gluconate complex with IV infusion vehicles other than 0.9% sodium chloride has not been evaluated. 

Admixture incompatibiiities Do not mix or coinfuse caspofungin with other medications, because there are no data available on the compatibility of caspofungin with other IV substances, additives, or medications. Do not use diluents containing dextrose ( -d-glucose), because caspofungin is not stable in diluents containing dextrose. 

The types of water-soluble polymers used for the thickening cement slurries, mortar and concrete are shown in Table 6.6. Although many polymers shown in Table 6.6 can be used to increase the viscosity of the water in the mix, they are not all pseudoplastic polymers compatible with cement systems. Only a few can be consistently combined with water-reducing admixtures (WRAs) and superplasticizers to produce concretes with cohesive yet highly flowable mixtures [40, 41, 43]. 

Compatibility with other admixtures (such as WRAs and superplasticizers) so that rheology of the mix is not significantly altered, set is not drastically extended, or heavy air-entrainment and foaming is not produced. 

Compatibility with other admixtures due to the inherent surfactant properties exhibited by most of the materials in classes A, B and C, their use with other admixtures such as water reducers should be evaluated in terms of the side effects on the plastic and hardened concrete, viz. severe set retardation and excessive air entrainment. The molecules of materials with fewer surfactant properties compete with the superplasticizer for adsorption sites on the cement particle. This will result in a higher dosage of the superplasticizer. 

Be compatible with other admixtures used in concrete. 

Two types of calcium nitrite-based corrosion inhibitors are currently marketed, viz. a set- and strength-accelerating type and a normal-setting type. The former increases the early strength development in concrete. This effect increases with the dosage. Both admixtures are compatible with all types of Portland cements and... 

The expansion achieved in concrete containing these admixtures is dependent on the type of aggregates used in the mixture. Thus the desired level of shrinkage compensation should take into account the modulus of the aggregate to be used on the job. The effect of cement and water contents on the extent of expansion should also be considered. Minimum cement content required to achieve desired expansion should be determined through mix trials. Compatibility with other admixtures may also need trials and the manufacturer s recommendation should be followed [80]. 

When confronted with cement-SP compatibility problems, the following action could be taken to identify whether the problem is primarily due to the reactivity of the cement or the poor performance of the admixture [125, 140] ... 

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