What is a vascath (quinton catheter, Nontunneled hemodialysis catheter)
A vascath is also known as a quinton catheter or a non-hemodialysis catheter. These catheters are plastic polymer tubes with two cannels, which are inserted in one of the neck veins (Can also be placed in the groin veins usually in emergencies or if the neck veins are occluded), with the tip of the catheter advancing through the length of the vein (eg. jugular vein and subclavian veins/brachiocephalic vein), and ending up in a larger vein (either superior or inferior vena cava or within the right atrium of the heart).
A Vascath also known as a Quinton is commonly inserted into a relatively medium to large caliber vein which can include the internal jugular, sub-clavian and femoral veins in that order. However, femoral veins are generally not preferred in the electively placed catheter due to the relatively elevated risk of infection. Femoral vascaths are generally reserved for patients who need emergent large bore vascular access ie. in the ER where femoral access is safer to be performed at beside even without imaging (Although at LA vascular we always advocate for image guidance with ultrasound). Once placed, these nontunneled catheters/vascaths/quinton catheters are secured to the skin by sutures, and are often primed with high dose heparin or alcohol or saline in the lumen to protect against thrombus formation or infection respectively. Once ready for dialysis the heparin/alcohol/saline lock are aspirated and then these catheter can be attached to the dialysis machine via each of the lumens at the ends (Blue and Red lumens) to allow for dialysis to be performed.
Vascath (Quinton catheter) Vs Permcath (Permacath)
Both of these catheters are large bore catheters although permcaths (Permacaths) tend to be slightly larger bore catheters. Both types of catheters are used for dialysis or plasmapheresis. Vascaths are non-tunneled catheters meaning they enter the vein directly without being tunneled under the skin. Permcaths on the other hand are tunneled under the skin and have a cuff that grows into the subcutaneous tissues along the tunneled tract. This tunneling and cuff are what allows permacaths to have a lower infection risk and a longer dwell time than vascaths.
Vascath/quinton catheter placement
Although these catheters can be placed at bedside especially in an emergent situation where large bore venous access is needed we advocate for placement under fluroscopic (confirms catheter tip position) and especially ultrasound guidance (confirms access into the vein while avoiding arterial puncture or puncture of the lung) by an interventional radiologist or qualified proceduralist. These catheters are often times placed at bedside and are commonly done in an emergency setting requiring an X-ray to be performed after placement to confirm its correct placement/positioning of the catheter and its tip (When the procedure is performed under fluoroscopic guidance the tip position is confirmed during the position obviating the need for post procedure x-ray). Another way to confirm that the catheter is appropriately within the venous system is to take blood samples although this is almost never done now a days given the margin of error for this method and widely available xray technology.
Vascath (Quinton catheter) removal
Unlike permcaths vascaths are not tunneled and directly enter into the vein. Because these central lines are not tunneled and do not have a cuff to grow into the subcutanous tissues like tunneled catheters (Permacaths) removal is as simple as cutting the retention suture which is a suture that is passed through the skin and attached to the catheter in order to anchor it to the skin and stop it from falling out.
After removing the retention suture we recommend lowering the head of the patients bed. If at all possible position the insertion site below the level of the patients heart generally referred to as trendelenberg position if tolerated. Apply pressure and a dry gauze over the insertion site as the catheter is removed in one swift motion during a breadth hold if possible. This is done to avoid the complication of a air embolism (life threatening complication of introducing air into the blood stream) which can occur if there is negative pressure in the chest while the catheter is removed. Never remove a central line with the patient sitting up or standing.
Groin Vs neck Vascath (Quinton Catheter)
Vascaths (non-tunneled hemodialysis catheters / Quintons) are considered temporary catheters and generally have a life span of as many as 10 days, if they are placed in the internal jugular or subclavian vein and a life span of 5 days if they have been placed in the femoral vein. This timeline is not definite as some non-tunneled catheters can remain in place for weeks at a time without issue. The reason for the shorter life span for those catheters placed in the groin/femoral vein is the increased infectious risk of these catheters compared with those that are placed in the neck/chest. The major reason for this is that these catheters unlike tunneled and cuffed hemodialysis catheters have a much higher tendency to get infected.
Vascath (Quinton catheter) complications and their prevention
Like all the other central venous catheters, vascath (Quinton catheter) insertion has minimal associated complications. The complication rate is significantly reduced when these catheters are inserted by interventional radiologist or a trained physicians under ultrasound and fluroscopic guidance. The major complications associated with these dialysis/large bore catheters are catheter related infections(CLABSI) and clotting of catheter lumens.
Infections in these cases can be prevented or delayed by proper hygiene and following proper protocol. In addition to this an occlusive dressing always needs to be placed over the catheter insertion site to minimize the risk of infections.
There are higher chances of clotting, when the vascath/Quinton is not being used, since the blood is in the static state. In order to prevent this an anti-coagulant is primed into the lumen of the catheter rather that injected into the blood stream. Anti-coagulant preferred for this task is heparin 1000 units /cc and the procedure is called heparin lock. Some patients are allergic to heparin and instead have their catheters locked with alcohol or saline. This lock fluid is always aspirated out of the catheter before anything is injected into the catheter.
Other complications such as air embolism, pneumothorax and arterial puncture are uncommon especially when the procedure is performed under image guidance.