From the Guidelines
When developing a compounding recipe for buffered hypertonic sodium solutions, the most important consideration is using milliequivalents of sodium instead of milligrams for calculations. This approach ensures that the tonicity of the buffered solution equals that of commercially available non-buffered hypertonic sodium solutions, which is crucial for maintaining the therapeutic effect of hypertonic solutions in managing intracranial pressure, as highlighted by the potential risks of hyperchloremia and metabolic acidosis associated with sodium chloride solutions 1. Using milliequivalents provides a more accurate measure of the sodium content's osmotic activity compared to using milligrams, which could lead to solutions with incorrect tonicity. Incorrect tonicity could potentially compromise patient safety and treatment efficacy.
The other options presented are less critical:
- Bedside mixing by nurses increases error risk, which could be mitigated with proper training and protocols, but this does not directly impact the formulation of the buffered hypertonic sodium solution.
- There's insufficient evidence that buffered solutions provide superior ICP control compared to non-buffered solutions, as the current evidence does not strongly support this claim 1.
- The osmolarity of different sodium products (acetate, bicarbonate, lactate) is not equivalent, making volume-based substitutions inappropriate during shortages, as substituting these products without considering their osmotic differences could lead to solutions with incorrect tonicity, potentially affecting patient safety and treatment efficacy.
Key considerations for developing a compounding recipe include:
- Ensuring the tonicity of the buffered solution matches that of commercially available non-buffered hypertonic sodium solutions
- Avoiding the use of sodium chloride solutions as the sole source of sodium due to the risk of hyperchloremia and metabolic acidosis, as discussed in the context of pediatric parenteral nutrition 1
- Potentially replacing part of the sodium intake with alternatives like sodium lactate or sodium acetate to reduce the risk of metabolic acidosis and hyperchloremia.
From the Research
Considerations for Developing a Compounding Recipe
When developing a compounding recipe for buffered hypertonic sodium solutions, several factors must be considered to ensure the safe and effective use of these solutions. The following points are crucial:
- Calculations: When determining the volumes of different sodium products to use for compounding, milliequivalents of sodium should be used instead of milligrams for calculations to ensure that the tonicity of the solution is equal to that of commercially available (i.e., non-buffered) hypertonic sodium solutions 2.
- Osmolarity: The osmolarity of all sodium products used for compounding buffered hypertonic solutions is not equivalent, and sodium acetate, sodium bicarbonate, and sodium lactate cannot be substituted using equal volumes when compounding buffered hypertonic solutions during shortages of these ingredients.
- Buffered Hypertonic Solutions: Buffered hypertonic solutions have been demonstrated to provide similar intracranial pressure (ICP) control compared with non-buffered (i.e., commercially available) solutions, and the compounding recipe for buffered hypertonic solutions should be designed to minimize the development of hyperchloremia 2.
- Nursing Considerations: Compounding recipes should be designed in such a way to make it easy for nurses to correctly mix hypertonic sodium products at the bedside to minimize the time to administration.
Key Factors in Hyperchloremia Development
The development of hyperchloremia in patients receiving hypertonic sodium chloride is associated with several factors, including:
- APACHE II Score: A higher APACHE II score is a significant predictor for hyperchloremia 3.
- Initial Serum Osmolality: Initial serum osmolality is a significant predictor for hyperchloremia 3.
- Total 3% Saline Volume: The total volume of 3% saline administered is a significant predictor for hyperchloremia 3.
- Total 23.4% Saline Volume: The total volume of 23.4% saline administered is a significant predictor for hyperchloremia 3.