Questions: A doctor orders dopamine IVPB to be infused at 10 mcg / kg / min. The patient weighs 220 lbs. Dopamine is supplied in an 800 mg per 500 mL bag. How many ml / hr would you set the pump to? (Round to the nearest tenth)

Solution Steps

To solve this problem, we need to follow these steps:

1. Convert the patient's weight from pounds to kilograms.
2. Calculate the required dose in micrograms per minute.
3. Convert the dose from micrograms per minute to milligrams per hour.
4. Determine the concentration of dopamine in the IV bag.
5. Calculate the infusion rate in milliliters per hour.

The patient's weight is given as 220 lbs. To convert this to kilograms, we use the conversion factor \(1 \text{ lb} = 0.453592 \text{ kg}\).

\[ \text{weight\_kg} = 220 \times 0.453592 = 99.79024 \text{ kg} \]

The doctor orders a dose of \(10 \, \mu\text{g} / \text{kg} / \text{min}\). Therefore, the required dose is:

\[ \text{dose\_mcg\_per\_min} = 10 \times 99.79024 = 997.9024 \, \mu\text{g} / \text{min} \]

To convert the dose from \(\mu\text{g} / \text{min}\) to \(\text{mg} / \text{hr}\), we use the following conversions: \(1 \, \mu\text{g} = 10^{-3} \, \text{mg}\) and \(1 \, \text{hr} = 60 \, \text{min}\).

\[ \text{dose\_mg\_per\_hr} = \left( \frac{997.9024}{1000} \right) \times 60 = 59.874144 \, \text{mg} / \text{hr} \]

The dopamine is supplied in an 800 mg per 500 mL bag. Therefore, the concentration is:

\[ \text{concentration\_mg\_per\_ml} = \frac{800}{500} = 1.6 \, \text{mg} / \text{mL} \]

To find the infusion rate in \(\text{mL} / \text{hr}\), we divide the dose in \(\text{mg} / \text{hr}\) by the concentration in \(\text{mg} / \text{mL}\):

\[ \text{infusion\_rate\_ml\_per\_hr} = \frac{59.874144}{1.6} = 37.42134 \, \text{mL} / \text{hr} \]

Rounding to the nearest tenth:

\[ \text{infusion\_rate\_ml\_per\_hr} = 37.4 \, \text{mL} / \text{hr} \]

Final Answer