Is magnesium infusion mixed with normal saline (0.9% sodium chloride) in a 250 milliliter (mL) bag?

From the Guidelines

Magnesium infusions are typically mixed with normal saline in a 250ml bag, as this is a common and compatible combination for intravenous administration. The standard preparation involves adding magnesium sulfate (usually 1-4 grams) to 250ml of normal saline (0.9% sodium chloride) for intravenous administration, as seen in a study where magnesium sulphate was added to standard treatment in acute severe asthma, resulting in significantly higher FEV1 % predicted at 4 hours 1. This dilution helps ensure proper distribution of the medication and reduces the risk of irritation at the infusion site. When administering magnesium infusions, it's essential to monitor the patient's vital signs, deep tendon reflexes, and serum magnesium levels to prevent toxicity, as noted in a randomised, double blind, placebo controlled trial of intravenous magnesium sulphate (2 g/50 ml normal saline) performed during standard treatment of patients with acute severe asthma 1. Some key points to consider when preparing magnesium infusions include:

• The compatibility of magnesium with normal saline makes this combination the standard approach for most clinical situations requiring magnesium supplementation
• The infusion rate should generally not exceed 1 gram per hour in non-emergent situations to avoid adverse effects such as hypotension, flushing, or respiratory depression
• Institutions may use different volumes or concentrations based on specific patient needs, particularly in cases of fluid restriction or when higher concentrations are required.

From the FDA Drug Label

In Pre-eclampsia or Eclampsia In severe pre-eclampsia or eclampsia, the total initial dose is 10 to 14 g of magnesium sulfate. Intravenously, a dose of 4 to 5 g in 250 mL of 5% Dextrose Injection, USP or 0. 9% Sodium Chloride Injection, USP may be infused. The answer is yes, magnesium infusion can be mixed with normal saline (0.9% Sodium Chloride Injection, USP) and in a 250ml bag, as indicated for the treatment of severe pre-eclampsia or eclampsia 2.

From the Research

Magnesium Infusion Details

• The provided studies do not directly address the question of whether magnesium infusion is mixed with normal saline and in a 250ml bag.
• However, some studies mention the use of magnesium sulfate in combination with normal saline:
  • In the study 3, patients in the magnesium group received intravenous magnesium sulfate, while the placebo group received the same volume of normal saline.
  • In the study 4, rats were administered normal saline or magnesium sulphate intraperitoneally.
• None of the studies provide information on the specific volume of the bag used for magnesium infusion.

Relevance of Studies

• The studies provided focus on various aspects of magnesium sulfate, such as its absorption, therapeutic effects, and potential toxicity.
• While they do not directly answer the question, they demonstrate the use of magnesium sulfate in medical settings, often in combination with normal saline.
• Further research would be needed to determine the specific details of magnesium infusion, including the volume of the bag used.