RD (Transes) Venipuncture ETS

• Evacuated Tube System is the most common and efficient system for blood collection
• Evacuated systems reduce the potential exposure of the healthcare worker to the specimen
• Physiologic factors affecting test results

  • Posture: Lipids, Enzymes, Proteins (Albumin) (PoLEP)
  • Diurnal rhythm: (DICPG)Cortisol, Iron, PTH, Growth Hormone
  • Exercise: (EC3L) Creatinine, CHONS, creatine kinase, LDH
  • Stress: (SGCW) WBC, cortisol, glucose
  • Diet: (DGL) Fasting affects Glucose and lipid
  • Smoking affects WBC count, cortisol, Hemoglobin (Smoking WCH)
• Composition of Blood


  1. In vivo blood is in a liquid form, but in vitro it will clot in a few minutes

  2. Freshly drawn blood into a glass tube appears as a translucent, dark fluid, which will start to clot forming a semisolid jelly-like mass

  3. If left undisturbed, the mass will begin to shrink in about 1 hour and complete retraction normally takes place within 24 hours
• Composition of Blood


  When fresh whole blood is mixed with anticoagulants, it can be separated into plasma and cellular components
• Types of Blood Components

  • Serum: liquid portion of whole blood that is allowed to clot normally
  • Plasma: liquid portion of whole blood mixed with substances that prevent clotting
• Environment factors associated with evacuated blood collection tubes

  • Ambient temperature
  • Altitude
  • Humidity
  • Sunlight
• Low temperature


  Pressure of the gas inside the tubes will decrease, leading to an increase in draw volume for the evacuated tube
• High temperature


  Reduction in draw volume, negative impact on the stability of certain tube additives
• Higher altitudes (>5000 feet)


  Lower blood volume draw
• Very high humidity


  Could lead to the migration of water vapor inside a tube containing a moisture-sensitive material
• Very low humidity


  Could hasten the escape of water vapor from a tube containing a wet additive
• CTAD mixture minimizes platelet activation after blood collection
• Venipuncture - ETS

  Three basic components: Multisample Needles, Tube Holder, Evacuated Tubes
• Multisample Needles with color-coded caps

  • 20 gauge - yellow
  • 21 gauge - green
  • 22 gauge - black
• Safety features of needles and tube holders provide immediate permanent containment and can be handled using one hand
• Fixed safety features provide a barrier between the hands and the needle after use
• It is recommended that storage for all vacutainer blood collection tubes should not exceed 25
• Barrier between the hands and the needle after use

  Provides a barrier between the hands and the needle after use
• Worker's hands should remain behind the needle


  Allow or require the worker’s hands to remain behind the needle at all times
• Needle safety


  • Integral part of the device and not an accessory
• Storage for all vacutainer blood collection tubes should not exceed 25 degrees C
• If plastic tubes reach higher temperatures, they may lose their vacuum or implode
• Evacuated tubes are intended for one-time use only
• Premature loss of vacuum can occur due to improper storage, opening the tube, dropping the tube, advancing the tube too far onto the needle before venipuncture, needle bevel becoming partially out of the skin during venipuncture, removing the tube before the vacuum is exhausted, stoppage of blood flow during the blood draw resulting in an underfilled tube called a partial draw or “short draw”
• Manufacturers guarantee the reliability of additives and tube vacuum until an expiration date printed on the label
• Shelf life of an evacuated tube is defined by the stability of the additive and vacuum retention
• Blood collection ideal gas law: PV= nRT
• Types of tubes and their stability

  • Sodium Fluoride – Serum
  • Sodium Flouride + anticoagulant (EDTA/Oxalate) – Plasma
  • Na Flouride – 3 days
  • Iodoacetate – 1 day
• Venipuncture procedure

  Patient interaction, Assemble supplies and equipment, ETS equipment preparation, Venipuncture, Specimen preparation
• ETS equipment preparation

  Select appropriate ETS tubes, Check the expiration date, Inspect the seal of the needle, Twist the needle cover apart, Screw end of the shorter needle into the threaded hub of the ETS tube holder, Place the first tube in the holder and use a slight clockwise twist to push the tube onto the needle during phlebotomy
• Venipuncture procedure


  Select general venipuncture location, Apply tourniquet, Select exact venipuncture site, Cleanse area, Inspect needle, Perform venipuncture, Release tourniquet, Position gauze over puncture site, Remove needle and apply pressure
• Specimen preparation

  Discard needle, Label specimens, Transport specimens promptly and properly
• Alternate sites for venipuncture if a vein cannot be located in either arm
• Veins in the feet should not be used without physician permission
• If a patient refuses to have blood drawn, notify nurse and document refusal
• Antiseptics used in blood collection

  • 70% ethyl alcohol
  • 70% Isopropyl Alcohol
  • Benzalkonium Chloride
  • Chlorhexidine gluconate
  • Hydrogen Peroxide
  • Povidone-Iodine (0.1%- 1% Iodine)
  • Tincture of Iodine
• If a venipuncture is unsuccessful after two attempts, notify the phlebotomy supervisor
• Problems encountered in phlebotomy: Refusal
• Venipuncture procedure


  1. Do not attempt to perform the venipuncture more than two times

  2. If two attempts are unsuccessful, notify the phlebotomy supervisor