The UIC Nomogram: A Simplified Approach to Individualized Digoxin Dosing in Heart Failure Patients
Posted: 14 Aug 2024, 21:19
The UIC (University of Illinois at Chicago) nomogram is a tool developed to help individualize digoxin dosing for patients with heart failure. Here's an explanation with a model case scenario:
Nomogram Digoxin.jpeg (100.77 KiB) Viewed 1331 times
Key features of the UIC nomogram:
1. It aims to achieve a target serum digoxin concentration (SDC) of 0.7 ng/mL.
2. It uses two key patient parameters:
- Ideal body weight (IBW)
- Creatinine clearance (CrCl) calculated using IBW
3. It provides a visual way to determine the appropriate daily digoxin dose.
Model case scenario:
Let's consider a hypothetical patient:
- 65-year-old male
- Height: 5'10" (178 cm)
- Actual weight: 200 lbs (90.7 kg)
- Serum creatinine: 1.2 mg/dL
Step 1: Calculate IBW
Using the Devine formula: IBW (male) = 50 kg + 2.3 kg for each inch over 5 feet
IBW = 50 + (2.3 x 10) = 73 kg
Step 2: Calculate CrCl using IBW
Using Cockcroft-Gault equation: CrCl = [(140 - age) x IBW] / (72 x SCr)
CrCl = [(140 - 65) x 73] / (72 x 1.2) = 56 mL/min
Step 3: Use the nomogram
Plot the patient's CrCl (56 mL/min) on the x-axis and IBW (73 kg) on the y-axis. The intersection point falls in the "0.125 mg daily" zone.
Therefore, the recommended daily digoxin dose for this patient would be 0.125 mg.
The nomogram simplifies the dosing process by visually integrating the two most important factors affecting digoxin pharmacokinetics (renal function and body size) and provides a quick, easy-to-use method for clinicians to determine an appropriate starting dose. This approach aims to achieve therapeutic SDCs more consistently than standard dosing practices, potentially improving efficacy and reducing toxicity risks.
Reference - https://www.ncbi.nlm.nih.gov/pmc/articl ... 614656.pdf
1. It aims to achieve a target serum digoxin concentration (SDC) of 0.7 ng/mL.
2. It uses two key patient parameters:
- Ideal body weight (IBW)
- Creatinine clearance (CrCl) calculated using IBW
3. It provides a visual way to determine the appropriate daily digoxin dose.
Model case scenario:
Let's consider a hypothetical patient:
- 65-year-old male
- Height: 5'10" (178 cm)
- Actual weight: 200 lbs (90.7 kg)
- Serum creatinine: 1.2 mg/dL
Step 1: Calculate IBW
Using the Devine formula: IBW (male) = 50 kg + 2.3 kg for each inch over 5 feet
IBW = 50 + (2.3 x 10) = 73 kg
Step 2: Calculate CrCl using IBW
Using Cockcroft-Gault equation: CrCl = [(140 - age) x IBW] / (72 x SCr)
CrCl = [(140 - 65) x 73] / (72 x 1.2) = 56 mL/min
Step 3: Use the nomogram
Plot the patient's CrCl (56 mL/min) on the x-axis and IBW (73 kg) on the y-axis. The intersection point falls in the "0.125 mg daily" zone.
Therefore, the recommended daily digoxin dose for this patient would be 0.125 mg.
The nomogram simplifies the dosing process by visually integrating the two most important factors affecting digoxin pharmacokinetics (renal function and body size) and provides a quick, easy-to-use method for clinicians to determine an appropriate starting dose. This approach aims to achieve therapeutic SDCs more consistently than standard dosing practices, potentially improving efficacy and reducing toxicity risks.
Reference - https://www.ncbi.nlm.nih.gov/pmc/articl ... 614656.pdf