Kidney Function Assessment and Dialysis

Introduction to Kidney Function Markers

Serum creatinine is the primary marker used to estimate glomerular filtration rate (GFR) in patients with kidney disease, as recommended by the American Diabetes Association 1
Creatinine clearance calculations depend on the measurement of both serum and urinary creatinine, according to the National Kidney Foundation 2

Decreased GFR leads to increased serum creatinine, which is a key indicator of kidney function, as stated by the American Diabetes Association 1
The presence of creatinine in extracellular fluids is the foundation for its use as a biomarker in kidney function assessment, with a strong evidence level 1

Creatinine is readily removed from extracellular fluid by dialysis, classified as "dialyzable" in extracorporeal treatments, as reported by the American College of Emergency Physicians 3
Removal of creatinine is one of the primary functions of dialysis in kidney failure, with a high level of clinical evidence 3

Serum creatinine is affected by hydration status, with a dilutional effect on serum creatinine in patients who have received significant volume expansion, as noted by the KDIGO guidelines 4
Fluid administration should be guided by hemodynamic assessment with specific indications and contraindications when managing Acute Kidney Injury (AKI), as recommended by the Kidney Disease: Improving Global Outcomes (KDIGO) guidelines 5
Fluid administration should be based on repeated assessment of overall fluid and hemodynamic status, according to the KDIGO guidelines 5
Caution is advised when giving additional fluids based solely on hemoglobin drop, as this could lead to volume overload, although this recommendation is from a less preferred source 6