Blood Chemistry: Analysis and Characteristics

• These notes cover blood chemistry, characteristics of blood, types of blood samples, extraction conditions, collection tubes, and key biochemical parameters.

General Information

• A blood chemistry test involves analyzing various elements in blood serum.
• A basic blood chemistry test consists of 6 elements, but can be extended to 27 or 30 elements.
• Glucose levels serve as a diagnostic for diabetes types I and II.
• Urea levels detect if there is diminished kidney function.
• Creatinine is useful for monitoring kidney function.
• Uric acid increase suggests gout or chronic kidney disease.
• Cholesterol levels indicate a risk of cardiovascular disease or dyslipidemia.
• Triglyceride increase can lead to coronary artery diseases.

Blood Characteristics

• Blood's red color is due to the presence of hemoglobin in red blood cells.
• Blood viscosity and density are related to the number of red blood cells and protein content.
• Blood pH is maintained between 7.35 and 7.45.
• The circulating blood volume in an individual represents about 8% of their body weight.

Types of Blood Samples

• Understanding the differences between serum, plasma, and whole blood is important for the correct use of collection tubes.
• Whole blood with an anticoagulant is separated into liquid and cells.
• Plasma is the liquid portion of blood when an anticoagulant is used, preserving fibrinogens for coagulation testing.
• Blood serum (or hematic serum) is the blood component after coagulation and removal of the resulting clot, equivalent to blood plasma but without coagulation proteins like fibrinogen.

Blood Extraction Conditions

• A strict fasting period of 8-12 hours is required.
• Individuals should not consume food or smoke after 10:00 p.m. the night before the test.
• Alcohol should not be consumed 24 hours before the exam.
• Certain vitamins can influence results; for example, vitamin C can alter creatinine.

Blood Collection Tubes

• Serum tubes include those without additives (red cap), with a coagulant activator (orange cap), and with a separating gel (yellow cap).
• Plasma tubes include those with sodium citrate (light blue cap), heparin (green cap), and glucose (gray cap).
• Whole blood tubes include EDTA (purple/lavender cap) and ESR tubes (black cap).

Biochemical Parameters

• Normal glucose levels: 70-105 mg/dL (Normal values in children: 40-100 mg/dL).
  • Elevated levels of glucose indicate Hyperglycemia or Diabetes.
  • Low levels of glucose indicates Hypoglycemia.
• Normal uric acid values:
  • Adult males: 4-8.5 mg/dL
  • Adult females: 2.5-7.5 mg/dL
  • Children: 2.5-5 mg/dL
  • High levels of uric acid indicate Hyperuricemia or Gout.
• Normal urea values: 7-20 mg/dL (Normal values in children: 5-18 mg/dL).
  • High levels of urea can indicate Hepatomegaly.
  • Low levels of urea can indicate renal insufficiency.
• Normal creatinine values:
  • Adult males: 0.7-1.3 mg/dL
  • Adult females: 0.5-1.2 mg/dL
  • Children: 0.2-1 mg/dL
  • High creatinine levels indicate renal insufficiency.
• Normal direct bilirubin value: 0.1-0.3 mg/100mL
  • High levels of direct bilirubin indicates Jaundice.
• Normal total bilirubin values: 0.3-1.0 mg/100 mL
  • High levels of total bilirubin can be indicate Hepatomegaly, Hepatitis, Cirrhosis, Cancer, or Malaria.
• Normal indirect bilirubin values: Less than 1.0 mg/mL
  • High levels of indirect bilirubin indicates Jaundice.
• Normal alkaline phosphatase values: 30-120 units per liter.
  • High levels of alkaline phosphatase indicate Infarction.
• Normal values for Gamma GT:
  • Males: 8-38 U/L
  • Females: 5-27 U/L
  • High levels of Gamma GT indicate Liver issues.
• Normal GOT values: 5-32 mU/mL
  • High levels of GOT indicate Liver issues.
• Normal GPT values: 7-33 mU/mL
  • High levels of GPT indicate Liver issues.
• Normal amylase values: 40-140 U/L
  • Abnormal levels can suggest pancreatic disfunction or cancer.
• Normal total cholesterol values: 100-200 mg/100mL
  • Abnormally high levels may mean Hypercholesterolemia, Arteriosclerosis, or Infarction.
• Normal HDL-Cholesterol values:
  • Males: above 45 mg/100mL
  • Females: above 55 mg/100mL
  • Abnormal levels can suggest hepatic insufficiency.
• Normal LDL-Cholesterol values: 60-180 mg/100mL
  • Abnormally high levels indicate Hypercholesterolemia.
• Normal total protein values: 6.4-8.3 gr/dl
  • Abnormal levels might indicate Proteinuria, kidney and hepatic insufficiency, and Cancer.
• Normal albumin values: 3.5 - 5 gr/dl
  • The diseases can be Proteinuria and Renal Insufficiency.
• Normal calcium values: 8.5 – 10.5 mg/100ml
  • The diseases can be Hypercalcemia (high calcium levels in the blood) and Hypocalcemia (low calcium levels in the blood).
• Normal potassium values: 3.5 – 5 mmol/L
  • The diseases can be Hyperkalemia (high levels of potassium in the blood) and Hypokalemia (low levels of potassium in the blood).
• Normal sodium values: 135 – 145 mEQ/L
  • The diseases can be Hypernatremia (high levels of sodium) and Hyponatremia (low levels of sodium).
• Normal chlorine values: 94 – 106 mEQ/L
  • The diseases can be Hyperchloremia (high chlorine levels in the blood) and Acidity/Gastritis.
• Normal phosphorus values: 2.9 – 5.0 mg/100 ml
  • The diseases can be Hyperphosphatemia (high phosphorus levels in the blood), kidney disease, and bone disease.

Clinical Interpretation

• Clinical analysis involves comparing observed values with reference limits provided by the laboratory.