To calculate the amount of dextrose being administered intravenously, you need to know the concentration of the dextrose solution and the volume being infused. According to the provided reference, the concentration is typically expressed as grams per 100 milliliters. Here's how you can calculate it:
Steps to Calculate Dextrose
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Identify the Dextrose Concentration: This is usually displayed as a percentage on the IV bag or solution. For example, D5W indicates a 5% dextrose solution, meaning there are 5 grams of dextrose in every 100 milliliters of solution. The reference mentions that "the number tells you how many grams there are in 100 milliliters."
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Determine the Total Infused Volume: You need to know the total volume of the dextrose solution that has been or will be administered. This is determined by the infusion rate (e.g., milliliters per hour) and the total infusion time (e.g., number of hours). For example, as the video reference states: "Next you determine volume in milliliters by looking at the rate and the number of hours the patient is receiving it."
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Calculate Total Grams of Dextrose:
- Use the dextrose concentration from step 1. Convert the percentage to a decimal if needed.
- Calculate how many 100 ml portions are within the total volume from step 2
- Multiply the number of 100 ml portions by the grams per 100ml from step one
Example
Let’s consider a practical example:
Scenario: A patient receives a D5W (5% dextrose) solution at a rate of 100 mL per hour for 8 hours.
- Dextrose Concentration: 5% dextrose (5 grams per 100 mL).
- Total Infused Volume: 100 mL/hour * 8 hours = 800 mL
- Calculation:
- 800 mL is equal to 800/100 = 8 portions of 100 ml
- Grams of dextrose: 8 portions * 5 grams/100 mL = 40 grams of dextrose.
Therefore, the patient will receive 40 grams of dextrose over 8 hours.
Another Example
A patient is receiving a D10W solution at a rate of 125 mL per hour for 6 hours.
- Dextrose Concentration: 10% dextrose (10 grams per 100 mL).
- Total Infused Volume: 125 mL/hour * 6 hours = 750 mL
- Calculation:
- 750 mL is equal to 750/100 = 7.5 portions of 100 mL
- Grams of dextrose: 7.5 portions * 10 grams/100 mL = 75 grams of dextrose.
In this case, the patient would receive 75 grams of dextrose over 6 hours.
Summary Table
| Step | Description | Example (Using Example 1) | Example (Using Example 2) |
|---|---|---|---|
| 1. Dextrose Concentration | Grams of dextrose per 100mL of solution | 5 grams per 100 mL (5% solution) | 10 grams per 100mL (10% solution) |
| 2. Total Infused Volume | Rate (mL/hour) multiplied by the infusion time (hours) | 100 mL/hour * 8 hours = 800 mL | 125mL/hour * 6 hours = 750mL |
| 3. Calculate Grams | Divide total volume by 100 then multiply by grams per 100mL | (800mL/100) * 5 grams = 40 grams | (750mL/100) * 10 grams = 75 grams |
By following these steps, you can effectively calculate the dextrose amount received by the patient.
