Question

Round the weight to the nearest tenth. A client weighs 154 lb. Heparin IV infusion: heparin sodium 20,000 units in \(1,000 \mathrm{~mL}\) D5W. The hospital protocol is to give a bolus to the client with 80 units/kg and start drip at 14 units/kg/hr. Calculate the following: a. Heparin bolus dosage b. Infusion rate for the IV drip units/hr c. Infusion rate in \(\mathrm{mL} / \mathrm{hr}\)

Short answer

a. 5600 units bolus, b. 980 units/hr, c. 49 mL/hr.

Step-by-step solution

Converting Weight to Kilograms

First, we need to convert the client's weight from pounds to kilograms. The conversion factor is approximately 1 kg = 2.2 lb.\[ \text{Weight in kg} = \frac{154}{2.2} \approx 70 \text{ kg} \]

Calculating Heparin Bolus Dosage

With the client's weight in kilograms, calculate the heparin bolus dosage using the protocol of 80 units/kg.\[ \text{Bolus dosage} = 80 \text{ units/kg} \times 70 \text{ kg} = 5600 \text{ units} \]

Calculating Heparin Infusion Rate (units/hr)

Next, calculate the infusion rate in units per hour. According to the protocol, this is 14 units/kg/hr.\[ \text{Infusion rate (units/hr)} = 14 \text{ units/kg/hr} \times 70 \text{ kg} = 980 \text{ units/hr} \]

Calculating Infusion Rate (mL/hr)

Use the concentration of the solution to determine the infusion rate in mL/hr. There are 20,000 units in 1,000 mL, so each mL contains 20 units.\[ \text{Infusion rate (mL/hr)} = \frac{980 \text{ units/hr}}{20 \text{ units/mL}} = 49 \text{ mL/hr} \]

Key concepts

Weight Conversion

When calculating dosages, converting a patient's weight from pounds to kilograms is often necessary. Many medications are dosed based on weight in kilograms, which is the standard in most medical protocols. To convert weight from pounds to kilograms, use the conversion factor: 1 kg = 2.2 lb.
This means that you divide the weight in pounds by 2.2 to get the weight in kilograms. For example, if a client weighs 154 pounds, the calculation would be:

• Weight in kg = \( \frac{154 \text{ lb}}{2.2} \)
• Weight in kg \( \approx 70 \text{ kg} \)

This simple calculation ensures you are using the correct weight in medication protocols, which helps in achieving precise dosing for optimum therapeutic effect.

Bolus Dosage

A bolus dosage refers to a specific amount of medication given over a short period. It's usually administered to quickly raise the medication's concentration in the blood to a therapeutic level. Using weight-based protocols ensures that each client receives a dose appropriate for their body mass.
To calculate the heparin bolus dosage for a person, use the client's weight in kilograms multiplied by the units per kilogram as per protocol:

• Bolus dosage = Units/kg \( \times \) Weight in kg
• For example, if the protocol requires 80 units/kg and the person weighs 70 kg, the calculation is: \( 80 \times 70 = 5600 \text{ units} \)

Administering the appropriate bolus dosage is critical in medical treatments to achieve the desired blood concentration level quickly.

Infusion Rate

The infusion rate is the speed at which a drug is administered intravenously, which is crucial when using medications like heparin that require consistent blood levels. Infusion rates are often calculated in units per hour (units/hr) and administered using infusion pumps.
To determine the infusion rate for heparin:

• Use the weight-based protocol of units/kg/hr
• Calculate: \( 14 \text{ units/kg/hr} \times 70 \text{ kg} = 980 \text{ units/hr} \)

This ensures the medication is delivered at a rate that maintains the desired therapeutic effect without interruption, optimizing patient outcomes.

Medication Protocol

A medication protocol is a standardized set of guidelines that provides clear instructions for the administration of drugs. Compliance with these protocols helps ensure patient safety and treatment efficacy. In the case of heparin, following the hospital's protocol aids in calculating both bolus dosages and infusion rates accurately.
The protocol outlines:

• The bolus dosage: 80 units/kg
• The infusion rate: 14 units/kg/hr

These instructions not only guide healthcare professionals but also help in determining precise infusion rates in mL/hr. For instance:

• Given the concentration of \( 20,000 \text{ units} \) in \( 1,000 \text{ mL} \), each mL holds 20 units.
• Calculate the solution infusion rate as: \( \frac{980 \text{ units/hr}}{20 \text{ units/mL}} = 49 \text{ mL/hr} \)

Adhering to these protocols ensures that patients receive the correct dosage at the appropriate rate, leading to optimal therapeutic outcomes.