Problem 11 - Calculate With Confidence

Question

Read the dosage information or label given for the following problems. Express body weight conversion to the nearest tenth where indicated and dosages to the nearest tenth. The recommended dosage for neonates receiving ceftazidime (Tazidime) is \(30 \mathrm{mg} / \mathrm{kg}\) q \(12 \mathrm{~h}\). The neonate weighs \(3,500 \mathrm{~g}\). a. What is the neonate's weight in kilograms to the nearest tenth? b. What is the safe dosage for this neonate?

Step-by-Step Solution

Answer

a. 3.5 kg b. 105 mg

Step 1: Convert Weight from Grams to Kilograms

The given weight of the neonate is 3,500 grams. To convert grams to kilograms, divide the number of grams by 1,000. The formula is:\[ \text{weight in kilograms} = \frac{\text{weight in grams}}{1,000} \]When we apply this:\[ \text{weight in kilograms} = \frac{3,500}{1,000} = 3.5 \, \text{kg} \]

Step 2: Calculate the Dosage

The recommended dosage is 30 mg/kg every 12 hours. To find out how many milligrams the neonate should receive per dose, multiply the dosage per kilogram by the neonate's weight in kilograms. The formula is:\[ \text{dosage} = 30 \, \text{mg/kg} \times \text{weight in kg} \]Substituting the given values:\[ \text{dosage} = 30 \, \text{mg/kg} \times 3.5 \, \text{kg} = 105 \, \text{mg} \]

Key Concepts

Weight Conversion

When working with medications and dosages, it's essential to accurately convert units. This is especially true for neonatal care where precision is critical. In the context of dosage calculations, **weight conversion** primarily involves converting grams to kilograms. This is because most medical dosages are calculated in terms of kilograms. Here's how you can make this conversion:

• Start by taking the weight in grams. For example, our neonate weighs \(3,500\) grams.
• To convert grams to kilograms, you divide by \(1,000\) since there are exactly \(1,000\) grams in a kilogram.

Hence, the calculation becomes:\[\text{weight in kilograms} = \frac{3,500}{1,000} = 3.5 \, \text{kg}\]So, the neonate’s weight is \(3.5\) kilograms. By following these simple steps, you ensure that further calculations are based on accurate and consistent units.

Neonate Care

The term **neonate** refers to a newborn child, particularly within the first 28 days post-birth. Neonates often require special medical attention and care due to their developmental vulnerabilities. This includes careful nutrition, temperature control, and safe administration of medication. All treatments, including medications, should be handled with utmost caution. For medication management, it is crucial to consider several unique aspects:

• **Weight-based dosages**: Medications are often dosed more frequently based on weight because of the rapid physiological changes in neonates. This ensures safety and efficacy.
• **Immature organ functions**: Organs like the liver and kidneys, which process medications, are still developing. This can affect how neonates metabolize and excrete drugs.
• **Sensitivity**: Neonates can be more sensitive to medications, making proper dosing crucial to avoid under or overdosing.

Understanding these factors ensures that medication dosing can be adjusted appropriately for neonates to promote health and safety.

Safe Dosage

Calculating a **safe dosage** for neonates involves accurately applying the weight-based guideline given for a specific drug. For our example with ceftazidime, the dosage is \(30 \, \text{mg/kg}\). To determine how much medication to give, follow these steps:

• First, ensure the weight conversion is accurate; here, it's \(3.5\) kg from grams.
• Next, multiply the dose per kilogram by the weight in kilograms.

The specific calculation constructed from these steps is:\[\text{dosage} = 30 \, \text{mg/kg} \times 3.5 \, \text{kg} = 105 \, \text{mg}\]This calculated dose of \(105\) mg every 12 hours considers the neonate's weight, ensuring it is within a safe **therapeutic range** and personalized to their needs. Safe dosing considers factors like potential side effects and ensures efficacy without exceeding safe limits.