Placing central venous cathethers, whether under ultrasound guidance or based off of your landmarks can be difficult and still prone to many complications. With the increased use and now standard of care for placing central lines with ultrasound guidance you would think we are immune to the “catastrophic” complication of an inadvertent arterial cannulation. But does ultrasound make us infalliable? Are there other methods that we can use to confirm venous placement of these large catheters?
Traditionally, we have looked at the color and pulsatility of blood coming from the needle hub before placement of the guidewire, but as you can imagine this is known to not be the most reliable; most of us aren’t going to go through the hassle of checking a blood gas off that blood either.
Troianos et al. found that ultrasound guidance reduced the incidence of arterial puncture from 8.4% down to 1.4% during attempted IJV cannulation. That’s great that it decreased the incidence, but when looking at the complications such as airway obstruction, hemothorax, pseudoaneurysms, AV fistulas and stroke, 1.4% is not something to sneeze at. So, keep in mind that although it does reduce the frequency of arterial puncture, it does not eliminate it entirely!
Despite the use of dynamic ultrasound guidance, there are still numerous reports of arterial placement of large bore catheters due to a couple reasons: 1. The needle tip may not be seen in the same plane of the ultrasound and confused with the shaft of the needle. 2. The needle may be in the vein, but the needle may move into the artery during placement of the guidewire after most of us have abandoned the ultrasound visualization. Ideally, after the guidewire is placed we should make it a habit to confirm the guidewire is in the vein before dilating the vessel.
Management of Arterial Cannulation
Despite our best efforts and even the most astute ultrasonographer there is always the potential for an inadvertent arterial cannulation, but what do we do once we have figured that out?
Option 1: Just old fashioned PULL AND PRESSURE: essentially this is exactly as it sounds. You pull out the catheter and apply pressure, just like any other line that is being removed. This is probably most reasonable for femoral artery cannulations, but there still remains a possibility of false aneurysms and AVF as late as 2 weeks after removal with the pull and pressure technique. Pull and pressure isn’t supposed to be used for carotid or subclavian arterial cannulations. One convincing piece of evidence is that there is an immediate stroke risk of 5.6% after removing carotid cannulations with this technique. Of 11,874 internal jugular vein cannulations, 20 ended up being carotid artery cannulations. 19 of these 20 were removed using the pull and pressure technique; six patients suffered complications and two of the patients died.
Option 2: Surgical ENDOVASCULAR repair: The more preferable method, especially for removal of carotid and subclavian arterial cannulations, is to involve our vascular surgeon colleagues. Just leave the line secured to the neck and get them involved. Some are going to request a formal ultrasound of the carotid or even sometimes a CT angio of the neck to check for extravasation, pseudoaneurysms, AVF and the location of the catheter.
Key points to remember
- Arterial cannulation can occur despite use of ultrasound guidance
- The American Society of Anesthesiologit’s guideline for CVC placement states that color and pulsatility are NOT reliable for distinguishing vein from artery.
- The pull/pressure technique is associated with significant risk of hematoma, airway obstruction, stroke, and false aneurysm especially when the site of arterial trauma cannot be effectively compressed
- Low IJV placement can injure the subclavian or innominate arteries
- Endovascular treatment is safe for management of arterial injuries that are difficult to expose surgically, such as those below or behind the clavicle.
- Normal Carotid Duplex after removal of a catheter form carotid artery does NOT rule out the possibility of a stroke
- False aneurysms or AV fistulae can occur LATE, up to 2 weeks after the “pull and pressure” technique so close follow up is needed
Post by: Dr. Yenis Paez-Perez, DO