Question

DD is a 66 y/o female with CKD. She is 5’5’’ and weighs 220lbs

with a serum creatinine of 1.4 mg/dL. Calculate DD’s CrCl.

Answer 1

To calculate DD's CrCl (creatinine clearance), we can use the Cockcroft-Gault equation. This equation estimates the creatinine clearance based on age, weight, sex, and serum creatinine level.

The formula for the Cockcroft-Gault equation is:

CrCl = ((140 - age) x weight) / (serum creatinine x 72) (multiplied by 0.85 for females)

Let's plug in the given values:

Age: 66 years

Weight: 220 lbs

Serum creatinine: 1.4 mg/dL

First, we need to calculate the adjusted body weight for females because DD is a 66 y/o female. We can use the equation:

Adjusted body weight (ABW) = ideal body weight + 0.4 * (actual weight - ideal body weight)

The ideal body weight for females is calculated as:

Ideal body weight (IBW) = 45.5 kg + 2.3 kg * (height in inches - 60)

Given that DD is 5'5'' (65 inches), we can calculate her IBW:

IBW = 45.5 kg + 2.3 kg * (65 inches - 60)

IBW = 45.5 kg + 2.3 kg * 5 inches

IBW = 45.5 kg + 11.5 kg

IBW = 57 kg

Now, let's calculate the ABW:

ABW = 57 kg + 0.4 * (220 lbs - 57 kg)

ABW = 57 kg + 0.4 * 163 lbs

ABW = 57 kg + 65.2 lbs

ABW = 122.2 lbs

Next, we can calculate the CrCl using the Cockcroft-Gault equation:

CrCl = ((140 - age) x weight) / (serum creatinine x 72) (multiplied by 0.85 for females)

CrCl = ((140 - 66) x 122.2 lbs) / (1.4 mg/dL x 72) (multiplied by 0.85)

CrCl = (74 x 122.2 lbs) / (1.4 mg/dL x 72) (multiplied by 0.85)

CrCl = 9061.6 lbs / 100.8 mg/dL (multiplied by 0.85)

CrCl = 89.85 L/day

Therefore, DD's CrCl is approximately 89.85 L/day.

Answer 2

Main Answer:

DD's CrCl is 48.5 mL/min, determined by the Cockcroft-Gault equation, essential for medication dosing in CKD management.

Step-by-step explanation:

In order to calculate DD's creatinine clearance (CrCl), the Cockcroft-Gault equation can be employed. The formula for CrCl is (140 - age) x weight (kg) x (0.85 if female) / (72 x serum creatinine). Plugging in DD's values, we get (140 - 66) x 220 x 0.85 / (72 x 1.4), resulting in a CrCl of 48.5 mL/min. This calculation is crucial in assessing renal function and adjusting medication dosages for individuals with chronic kidney disease (CKD).

It takes into account factors such as age, weight, and gender, providing a more accurate reflection of renal clearance than serum creatinine alone. Monitoring CrCl is essential in managing medications that are primarily excreted through the kidneys, ensuring proper drug dosages and minimizing the risk of adverse effects. As a quantitative measure of kidney function, CrCl assists healthcare professionals in tailoring treatment plans for patients like DD, optimizing therapeutic outcomes and minimizing the potential for medication-related complications.