WHAT ARE MIXED OR PARENTERAL SOLUTIONS? - CHEMISTRY - 2024

The mixed parenteral solutions or are sterile preparations containing one or more active principles for administration by injection, infusion or implantation into the body. They are stored in single-dose or multi-dose containers (Parenteral solutions (By injection), 2017).

Parenteral preparations may require the use of excipients such as solvents, substances to improve solubility, suspending agents, buffering agents, substances to make the preparation isotonic with blood, stabilizers or antimicrobial preservatives. The addition of excipients is kept to a minimum.

Water for injections is used as a vehicle for aqueous injections. Sterilization at this stage can be omitted as long as the preparation is terminally sterilized.

For non-aqueous injections, oils of vegetable origin are used as vehicles (The International Pharmacopoeia, 2016).

When talking about mixed parenteral solutions, it refers to a type of parenteral solution where physiological serum is mixed with glucose serum.

Mixed solutions, also called glucosaline solution, consist of anhydrous glucose, glucose monohydrate, and sodium chloride.

These solutions are generally found in isotonic, hypertonic and hypotonic ways, with a specific use of each.

Solutions are prepared by dissolving 50 grams of glucose and 1.8 grams of sodium chloride in each liter of solution (320 mOsm / l) in the case of the isotonic solution.

The hypotonic solution is prepared by dissolving 33 grams of glucose and 3 grams of sodium chloride in each liter of solution.

Hypertonic is prepared with 0.9 grams of sodium chloride and 5 grams of glucose per 100 milliliters of solution (560 mOsm / l).

Importance of mixed solutions in parenteral nutrition

We all need food to live. Sometimes a person cannot consume any food or their intake is insufficient due to illness.

The stomach or intestine may not function normally, or a person may have had surgery to remove some or all of these organs.

Nutritional support in intensive care represents a challenge, but it is fortunate that its delivery and follow-up can be closely monitored (Pierre Singer, 2009).

In these cases, nutrition must be delivered in a different way. One method is "parenteral nutrition" (intravenous nutrition) (American Society for Parenteral and Enteral Nutrition (ASPEN), SF).

Parenteral nutrition continues to be a topic of intense research interest. It has now been shown that it does not offer any advantage, but is associated with a higher frequency of complications, compared to enteral nutrition in patients with gastrointestinal cancer.

Nutritional support administered intraportal, combined with multimodal analgesia, appears to offer certain metabolic and clinical advantages compared to that administered through systemic veins.

However, parenteral nutrition does not prevent the decrease in antioxidant capacity seen after major surgery, and feeding lines present an additional risk factor for systemic candidiasis in the intensive care setting (Paul Kitchen, 2003).

Glucosaline solutions provide the patient between 132 and 200 kCal for each liter of solution. Sodium and chlorine ions are the main inorganic components of the extracellular fluid, maintaining an appropriate osmotic pressure of the blood plasma and the extracellular fluid.

Isotonic glucosaline solution fills a deficit of body fluids during dehydration.

Hypertonic Glucosaline solution for intravenous injection provides a correction of the osmotic pressure of the extracellular fluid and blood plasma. When applied topically in ophthalmology, Glucosaline (sodium chloride) has anti-edema effect.

When should a mixed solution be used?

Glucosaline as an isotonic solution is prescribed when there is dehydration of various origins, to maintain the volume of blood plasma during and after surgery and as a solvent for various drugs.

The solution is used in pediatric cases with hypertonic dehydration, insulin coma and hepatic coma.

Hypertonic solution is prescribed when:

• There are violations of water-electrolyte metabolism, such as a lack of sodium and chlorine ions.
• Hypoosmotic sehydration of various origins (due to prolonged vomiting, diarrhea, burns with gastric fistula.
• Pulmonary hemorrhage
• Intestinal bleeding.

The isotonic solution is prescribed for fluid therapy and maintenance of hyperosmolar coma in a diabetic patient with glycemia greater than 300 mg / dl.

This solution does not contain any added bacteriostatic agent, antimicrobial agent or buffer, and is intended only as a single dose injection. When smaller doses are required, the unused portion should be discarded.

Contradictions and side effects

Parenteral nutrition should not be used routinely in patients with an intact GI tract (Thomas, 2017). Compared to enteral nutrition, it has the following drawbacks:

-Causes more complications.

-Does not preserve the structure and function of the GI tract.

-It is more expensive.

Among the side effects that mixed solutions can cause, we can find reactions such as: nausea, vomiting, diarrhea, stomach cramps, thirst, lacrimation, sweating, fever, tachycardia, hypertension, kidney dysfunction, edema, shortness of breath, muscle spasms and hypertonicity.

Glycosylated sera are contraindicated when there are hypernatremia, hyperhydration, the threat of pulmonary edema, cerebral edema, hyperchloremia, hyperlacticidemia, head trauma, hypervolemia, and severe kidney disease.

Caution should be taken with the use of large amounts of glucosaline solution in patients with impaired renal excretory function and hypokalaemia.

Injection of large amounts of solution can lead to chloride acidosis, hyperhydration, increased excretion of potassium from the body.

Hypertonic Glucosaline solution should not be applied subcutaneously and intramuscularly.

With prolonged use it is necessary to monitor the concentration of electrolytes in the plasma and the daily production of urine. The temperature of the infusion solution should be 38 ° C (MEDICATION: GLUCOSALINE, SF).

References

1. American Society for Parenteral and Enteral Nutrition (ASPEN). (SF). What Is Parenteral Nutrition. Recovered from nutritioncare.org.
2. MEDICATION: GLUCOSALINE. (SF). Recovered from medicatione.com.
3. Parenteral solutions (By injection). (2017, June 16). Recovered from pennstatehershey.adam.com.
4. Paul Kitchen, AF (2003). Parenteral Nutrition. Recovered from medscape.com.
5. Pierre Singer, PS (2009). ESPEN Guidelines on Parenteral Nutrition: Intensive care. Clinical Nutrition 28, 387–400.
6. The International Pharmacopoeia. (2016). Parenteral preparations. Recovered from apps.who.int.
7. Thomas, DR (2017, February). Total Parenteral Nutrition (TPN). Recovered from msdmanuals.com.