Dimensional Analysis for Drug and Dosage Calculation

Introduction to Dimensional Analysis

• Purpose: Solve drug and dosage calculation problems in nursing.
• Pre-requisite: Familiarity with the metric table.
  • Metric table available at RegisteredNurseRN.com/metric-table.
  • Useful to memorize for ease in solving problems.

Understanding Dimensional Analysis

• Definition: A technique used for problem-solving where you multiply values by one without changing their value.
• Method: Set up problems using a top and bottom approach, but they are not fractions.
• Objective: Solve for a specified unit by canceling out other units diagonally.

Example Problems and Solutions

Problem 1: Converting Grams to Milligrams

• Problem: 8 grams equals how many milligrams?
• Solution Steps:
  1. Set up: 8 grams = ? milligrams.
  2. Use metric table: 1 gram = 1000 milligrams.
  3. Multiply across top (8 x 1000 = 8000) and divide by the bottom (8000/1 = 8000).
  4. Result: 8 grams = 8000 milligrams.

Problem 2: Converting Grams to Micrograms

• Problem: 8 grams equals how many micrograms?
• Solution Steps:
  1. Set up: 8 grams = ? micrograms.
  2. Convert to milligrams first: 1 gram = 1000 milligrams.
  3. Convert to micrograms: 1 milligram = 1000 micrograms.
  4. Multiply (8 x 1000 x 1000 = 8,000,000) and divide by 1.
  5. Result: 8 grams = 8,000,000 micrograms.

Problem 3: Converting Milliliters to Ounces

• Problem: 100 milliliters equals how many ounces?
• Solution Steps:
  1. Set up: 100 milliliters = ? ounces.
  2. Convert via tablespoons: 15 milliliters = 1 tablespoon.
  3. 2 tablespoons = 1 ounce.
  4. Multiply and divide: (100 x 1 x 1) / (15 x 2).
  5. Result: 100 milliliters = 3 ounces.

Additional Resources

• Website: RegisteredNurseRN.com for practice quizzes and further tutorials.
• Video Series: Tutorials on more complex problems like IV boluses and dosage based on weight.

Conclusion

• Dimensional analysis is a powerful tool in nursing for accurate dosage calculations.
• Practice using available resources to gain proficiency.