Glucose Infusion Rate Calculator
This calculator helps determine the appropriate rate of glucose infusion for patients, often used in medical settings to manage blood sugar levels.
Results
Understanding Glucose Infusion Rate
The glucose infusion rate (GIR) is a critical parameter in managing a patient's blood glucose levels, especially in situations where oral intake is not possible or sufficient. This is common in neonatal intensive care units (NICUs), during surgical procedures, or in patients with metabolic disorders.
How it Works:
The calculator uses the following formula:
Rate (mL/hr) = (Patient Weight (kg) * Target Infusion Rate (mg/kg/min) * 60 min/hr) / (Infusion Solution Glucose Concentration (g/dL) * 10 mg/dL/g * 10 dL/L)
Let's break down the components:
- Patient Weight (kg): The total body weight of the patient.
- Target Infusion Rate (mg/kg/min): This is a physician-determined rate of glucose administration per kilogram of body weight per minute. Common ranges are typically between 2 to 12 mg/kg/min, but this can vary significantly based on clinical status.
- Infusion Solution Glucose Concentration (%): The percentage of glucose in the intravenous solution. For example, a 10% dextrose solution means there are 10 grams of dextrose in 100 mL of solution.
- Conversion Factors: We use constants to convert between units (e.g., mg to g, dL to L, minutes to hours) to arrive at the final infusion rate in mL per hour.
Example Calculation:
Let's consider a patient weighing 70 kg who requires a target infusion rate of 2 mg/kg/min. The intravenous solution is a 10% dextrose solution.
- Patient Weight = 70 kg
- Target Infusion Rate = 2 mg/kg/min
- Infusion Solution Concentration = 10% (which is 10 g/dL or 100 mg/mL)
Calculation:
First, convert the infusion solution concentration to mg/mL:
10% = 10 g/100 mL = 100 g/L = 100000 mg/L
Alternatively, and more commonly for this calculation, 10% means 10g of glucose per 100mL. So, 10g = 10,000mg. Therefore, 100mg/mL.
Amount of glucose needed per minute: 70 kg * 2 mg/kg/min = 140 mg/min
Now, calculate the volume of the 10% dextrose solution needed to deliver 140 mg/min:
Volume (mL/min) = (140 mg/min) / (100 mg/mL) = 1.4 mL/min
Convert this to mL/hr:
1.4 mL/min * 60 min/hr = 84 mL/hr
Therefore, the calculated glucose infusion rate is 84 mL/hr.