Glomerular Filtration Rate (GFR)

Overview

1. Glomerular filtration rate
   1. Normal Value Range
   2. Pathophysiology
   3. Special considerations
   4. Elevations in GFR
   5. Decreases in GFR

Nursing Points

General

1. Normal value range
   1. 90-120 mL/min/1.73m2
   2. Indication of kidney dysfunction
   3. Based on age, gender, race
2. Pathophysiology
   1. Blood is filtered in the glomerulus
   2. Glomeruli filter waste from blood
   3. Damage to the glomeruli allows for loss of important cells
      1. RBCs
      2. WBCs
      3. Proteins
   4. Slower glomerular filtration means buildup of wastes and fluids in the body
   5. Because glomeruli are the first stage of urine formation, GFR helps to indicate current or potential kidney damage
3. Special considerations
   1. Serum
      1. Green, red or lavender top tube
   2. Often sent with other renal labs
   3. Consider creatinine clearance
      1. 24 hour urine collection
4. Elevations in GFR
   1. Increased GFR with albumin in urine
      1. Caused by renal disease
      2. Rarely occurring
5. Decreases in GFR
   1. Kidney disease
      1. Injury or disease specific to the glomerulus
      2. Damage to nephrons/glomeruli from AKI
      3. Long term loss of kidney function due to CKD
   2. Kidney toxicity
   3. Diabetes
   4. Hypertension

Assessment

1. Assess patient’s nutritional status
2. Assess urine output
3. Consider other causes for increase in creatinine
   1. Muscle

Therapeutic Management

1. Treat cause of renal insufficiency
   1. Dialysis
   2. Medication
   3. Lifestyle alteration
   4. Toxicity
   5. Infection/Antibiotics

Nursing Concepts

1. Lab Values
2. Elimination