Pharmacology Electrolytes #4

Question

Which client laboratory findings will most likely result in an immediate prescription from the healthcare provider for intervention? (see serum lab results below)

Serum lab results:

  • Sodium 136 mmol/L
  • Calcium 9.0 mg/dL
  • Magnesium 1.0 mg/dL
  • Potassium 3.5
  • Hematocrit 40%
  • Creatinine 1.2 mg/dL

Answers

  1. Sodium level
    • Rationale:

      This answer is not correct because a sodium level of 136 mmol/L is within normal range of 135-145 mmol/L. The magnesium level of 1.0 mg/dL is a low level compared to the normal level of 1.7 to 2.2 mg/dl. The client will be symptomatic and need treatment.

  2. Calcium level
    • Rationale:

      This answer is not correct because a calcium level of 9.0 mg/dL is within the normal level of 8.5-10.2 mg/dL. The magnesium level of 1.0 mg/dL is a low level compared to the normal level of 1.7 to 2.2 mg/dl. The client will be symptomatic and need treatment.

  3. Magnesium level
    • Rationale:

      This answer is correct because the magnesium level of 1.0 mg/dL is a low level compared to the normal level of 1.7 to 2.2 mg/dl. The client will be symptomatic and need treatment.

  4. Potassium level
    • Rationale:

      This answer is not correct because a potassium level of 3.5 mmol/L is within the normal range of 3.5-5.3 mmol/L. The magnesium level of 1.0 mg/dL is a low level compared to the normal level of 1.7 to 2.2 mg/dl. The client will be symptomatic and need treatment.

Overview

Electrolyte imbalances can be very serious. A serum magnesium level of 1.0 mg/dL requires immediate intervention.

Explanation

Learning Outcomes

Hypomagnesemia is when the blood has a decreased level of magnesium. The normal level of magnesium is 1.7 to 2.2 mg/dl. Magnesium helps regulate body functions such as glycolysis, blood pressure, blood glucose control, and muscle and nerve function. Symptoms of hypomagnesemia include nausea, vomiting, weakness, fatigue, tetany, and tremor. Treatment of symptomatic hypomagnesemia or consistently less than 1.25 mg/dL includes oral administration of magnesium. If symptoms are severe, such as seizures, magnesium sulfate IV is administered.

Test Taking Tip

Even if you do not remember some labs that are less common, such as magnesium levels, eliminate other labs that you do know, such as more common lab levels of Hct, creatinine, calcium, potassium, and sodium.

Video Rationale