Guide to Commonly Tested Labs

Whether a patient is visiting for routine physical exams or coming in for a minor procedure, chances are the healthcare practitioner will order labs to be drawn. Typically the healthcare practitioner will be the one to interpret the results of blood tests and labs, however, it is expected that the nurses have a strong working knowledge of the most commonly tested labs, normal lab value ranges, and their implications. Please note: the normal range of lab values may differ by location, altitude, age, gender, etc.

This resource is not intended to be a complete list of all labs and their common causes. 
 

Guide to Commonly Tested Labs

LAB LOW NORMAL RANGE HIGH

Na

Sodium
Common Causes: AIDS, CHF, cirrhosis, heavy sweating, nephrotic syndrome, NG suctioning, vomiting,

135 — 145

Common Causes: dehydration, dietary intake, diabetes, IV

Glu

Glucose
Common Causes:
too much insulin, hypoglycemic meds or propranolol, adrenal issues, malnutrition
  • < 40 is critical

70 — 110

Common Causes: diabetes, cushings, chronic pancreatitis
  • >~350 is critical

Phos

Phosphorus
Common Causes: alcoholism, diarrhea, hypercalcemia, refeeding syndrome, vomiting, vitamin D deficiency

2.5 — 4.5

Common Causes: hypoparathyroidism, cirrhosis, renal failure, diabetic ketoacidosis

K

Potassium
Common Causes: alkolosis, ascites, burns, diarrhea, low dietary intake, vomiting and diuretics, insulin

3.6 — 5.2

Common Causes: acidosis, dehydration, beta blockers, renal dysfunction

BUN

Blood Urea Nitrogen
Common Causes:
low protein diet, fluid overload, liver failure, nephrotic syndrome, starvation

8 — 25

Common Causes:
burns, dehydration, GI bleeding, post-renal obstruction, renal failure, shock, stress

Cr

Creatinine
Common Causes:
low muscle mass, vegetarian diet, pregnancy, advanced liver disease

0.6 — 1.2

Common Causes: hypothyroidism, renal failure, urinary tract obstruction

Alb

Albumin
Common Causes: chronic liver disease, kidney disease, CHF, diabetes, malnutrition, acute infections

3.4 — 5.4

Common Causes: dehydration, shock,
high protein diet

Ca

Calcium
Common Causes: alcoholism, chronic renal failure, Mg deficiency, vitamin D deficiency, pancreatitis

8.5 — 10.5

Common Causes:
bone cancer, renal failure, hyperparathyroidism

TG

Triglycerides
Common Causes: Hyperthyroidism, malabsorption, malnutrition

< 150

Common Causes: 
cirrhosis, diabetes, fatty liver disease, pancreatitis, hypothyroidism, nephrotic syndrome, renal failure, obesity, stress

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