Central venous placement: Technique
Basic, Basic Sciences
Knowledge of CVC kits, anatomy, and proper insertion technique are critical to the success of central venous cannulation. The most common insertion sites are the internal jugular vein, subclavian vein, and femoral vein. I will first discuss the modified Seldinger technique for central venous cannulation here.
Step 1: Familiarize yourself with the equipment. This generally includes:
- Sterile mask, gloves and gown
- Sterile prep solution and drapes
- 5mL syringe with 25g needle for local anesthetic administration + local anesthetic (i.e., lidocaine 1%)
- 22-gauge, 1.5-inch needle
- 18- or 20-gauge intravenous catheter (over a needle) on a syringe, or 18-gauge hollow- bore needle
- Pressure tubing
- Central venous catheter with dilator
Step 2: Using sterile technique, put on gown and gloves, open the CVC kit, and drape the patient. Fill the 5mL syringe with lidocaine and flush each port of the central venous catheter and lock each port except for the distal port (which the guide wire will eventually thread through).
Step 3: Place the patient in shallow Trendelenburg if the internal jugular vein is to be cannulated. Inject local anesthetic around the site, gradually working towards the vein. Pull back on the plunger as you go deeper to ensure that you don’t inject local anesthetic into the vein.
Step 4: Attach a syringe to the large syringe provided in the kit. Using the ultrasound pobe, identify the vein of interest. The internal jugular vein normally runs lateral to the carotid artery (more superficial on ultrasonography); however, variant anatomy may occur where the carotid artery runs laterally. The femoral vein lies medial to the femoral artery below the inguinal ligament. Identifying the vein vs. artery can be done by applying pressure with the ultrasound probe (the vein is generally more compressible than the artery). Additionally, one can often observe the pulsation of the artery. Advance the needle slowly and aspirate once you believe to have cannulated the vein.
Step 5: Remove the syringe, and be sure to keep the needle still to ensure it remains within the vein.
Step 6: Insert the guide wire into the end of the needle and slowly advance the wire. The guide wire should advance with little resistance. Should you encounter resistance, slowly retract the guide wire and attempt advancement once again.
Step 7: Remove the needle over the guide wire. Be sure to keep one hand firmly on the guide wire at all times to ensure the wire stays in place.
Step 8: Using the scalpel, make a knick in the skin where the guide wire exits. Place the dilator over the guide wire and insert into the skin. Remove the dilator once you are able to insert it.
Step 9: Place the catheter over the guide wire. Remember to keep one hand on the guide wire at all times so that it remains in place. Advance the catheter until it is in place, remove the guide wire (while keeping one hand on the catheter at all times) and clamp the final port. One at a time, flush each port with saline (or heparin) and re-clamp.
Step 10: Suture the catheter to the skin and apply sterile dressing to the skin. Be sure to order a chest radiograph to assess proper placement and absence of pneumothorax.