Phlebotomy: Blood Collection Methods

Phlebotomy Overview

• Phlebotomy involves collecting blood samples from patients through different methods
• Three main methods of blood collection: arterial puncture, capillary puncture, and venipuncture

Arterial Punctures

• Collected by physicians
• Risky due to blood being under pressure
• Used for arterial blood gases, acidity, alkalinity, oxygen, and carbon dioxide tests
• Common sites: radial, brachial, and femoral arteries
• Indications: urgent ABG tests, e.g., accident victims with chest injuries, comatose patients, or patients with severe breathing problems

Capillary Punctures

• Uses different types of materials: lancets (simple and retractable), automatic (pen devices), and adjustable depths
• Advantages: small volume of blood, less invasive, and rapid tests/POCT
• Disadvantages: small volume of blood
• Performed perpendicular to the skin, with "milking" technique
• Different sites for different patients, easier to acquire and perform

Venipunctures

• Uses different types of syringes: slip tip and luer lock
• Syringe sizes: 3 ml, 5 ml, 10 ml, and 20 ml
• Needle sizes: 21G, 22G, 23G, and 25G (smaller gauge means larger diameter)
• Needle lengths: 1 inch and 1.5 inch
• Vacutainer hubs for evacuated tube system
• Advantages: large volume of blood, accurate results
• Disadvantages: more invasive than capillary punctures

Other Phlebotomy Materials

• Capillary punctures: gauze (wet and dry), iodine tincture, lancets, micro-capillary tubes, paediatric blood tubes, regular blood tubes, and rapid/POCT devices
• Venipuncture syringe method: needles, syringes, gauze (wet and dry), iodine tincture, lancets, regular blood tubes, blood culture bottles
• Other materials: tourniquet, spot bandages, bio bins, and sharp disposal bins

Learn about different methods of blood collection, including arterial, capillary, and venipuncture, and understand the advantages and disadvantages of each technique.