The LSUHSC New Orleans Emergency Medicine Interest Group Presents The Student Procedure Manual

Venipuncture

Indications

• Allows the sampling of venous blood for the diagnosis of electrolyte imbalances, infection, blood type and crossmatching, disease states, drug levels, etc.

Contraindications
Locations to avoid drawing blood-

• Extremities with massive edema, bums, traumatic injury, sclerosis, phlebitis, or thrombosis, as circulation may be compromised or occluded in these areas
  
• Ipsilateral arm to mastectomy, neck trauma, indwelling fistula
  
• Vein that may be compromised due to localized trauma
  
• Areas affected by cellulitis, as penetration into area may seed the central circulation with bacteria

Equipment

• Alcohol swab
  
• Gauze
  
• Tourniquet, usually rubber tubing or strap Hollow bore needle; usually 20-24 gauge, larger gauges used for smaller veins
  
• Syringe or Vaccutainer system
  
• Latex Gloves
  
• Blood receptacle (test tubes, blood culture vials etc.)

Preparation

• Explain [what and why you are going to do you are going to do to the patient prior to performing the procedure (if time and circumstances allow)]
  
• Before beginning procedure have all equipment assembled and easily accessible, as this procedure is often done by a lone practitioner
  
• Always employ universal precautions when contact with bodily fluids is a possibility

Procedure

1. Preferred site is in the antecubital fossa; if veins are inaccessible there, the dorsum of the hand or the radial side of the wrist is often used
   
2. Place tourniquet 3-4 cms proximal to intended puncture site and stabilize the patient's arm to minimize movement
   
3. If vein is inapparent, have the patient tense, and then relax local muscles repeatedly to increase blood flow to the area, apply a warm compress to the area, or tap sharply over the vein to induce reflexive vasodilation
   
4. Wipe intended puncture site with alcohol swab in a circular motion from the center outward about 4-5 cm
   
5. With your non-dominant hand, pull skin taut to stabilize vein
   
6. Puncture the skin rapidly with the catheter needle bevel up at a 30' angle directly over the vein; once in the subcutaneous space, level off the angle of insertion to nearly parallel with skin surface; if using a syringe, maintain negative pressure once subcutaneous space is reached, if using Vaccutainer system, push test tube onto needle to create negative pressure
   
7. Once subcutaneous space is reached, advance the needle into the tissue until blood flow into receptacle begins; at this time, draw off as much blood as will be needed for all anticipated tests
   
8. Remove the tourniquet with your non-dominant hand
   
9. Place gauze over puncture site, then quickly remove the needle
   
10. Apply pressure to the puncture site for 3-5 minutes and twice this duration for patients with coagulopathies
    
11. Tape gauze in place
    

Complications

• Bruising at or near puncture site; to reduce occurrence of bruising apply direct pressure to puncture area immediately after needle is removed and elevate extremity
  
• Cellulitis, or phlebitis- uncommon with this procedure,, but may result from inadequate site preparation
  
• Nerve, tendon, or arterial damage; due to direct injury from needle, or from compression by localized hematoma

Follow Up

• Inspect puncture site for swelling, or pain after 3-5 minutes of direct pressure
  
• Check for continued bleeding from puncture site, especiallv in patients with coagulopathies