Final answer:
The creatinine clearance (CrCl) for a 22-year-old female with a serum creatinine of 0.7 mg/dL is calculated using the Cockcroft-Gault equation. After converting her weight and height, the uncorrected CrCl is approximately 70.73 ml/min. Corrected for body surface area, the CrCl is approximately 84.34 ml/min/1.73 m2, which is within the normal range.
Step-by-step explanation:
To calculate the creatinine clearance (CrCl) for a 22-year-old female with a serum creatinine of 0.7 mg/dL, we use the Cockcroft-Gault equation:
CrCl = ((140 - age) × weight in kg × [0.85 if female]) / (72 × serum creatinine)
First, we need to convert the weight from pounds to kilograms (1 lb = 0.453592 kg) and the height from inches to centimeters (1 inch = 2.54 cm):
92 lbs × 0.453592 = 41.73 kg
5'1'' = 61 inches × 2.54 = 154.94 cm
Next, we calculate the CrCl:
CrCl = ((140 - 22) × 41.73 × 0.85) / (72 × 0.7)
CrCl = (118 × 41.73 × 0.85) / (50.4)
CrCl = (4203.77 × 0.85) / 50.4
CrCl ≈ 70.73 ml/min
However, to allow comparison of results between people of different sizes, we correct the CrCl for the body surface area (BSA):
BSA = 0.007184 × Weight0.425 × Height0.725
BSA ≈ 0.007184 × 41.730.425 × 154.940.725
BSA ≈ 1.45 m2
Finally, we correct the CrCl for BSA:
CrCl-corrected = CrCl × (1.73 / BSA)
CrCl-corrected ≈ 70.73 × (1.73 / 1.45)
CrCl-corrected ≈ 84.34 ml/min/1.73 m2
RR's corrected CrCl is approximately 84.34 ml/min/1.73 m2, which is within the normal range for an adult female less than 40 years old.