Peripherally Inserted Central Catheters and Nontunneled Central Venous Catheters



Peripherally Inserted Central Catheters and Nontunneled Central Venous Catheters


Joseph A. Hughes, Colin P. Cantwell and Peter N. Waybill


Peripherally inserted central catheters (PICCs) and nontunneled central venous catheters (CVCs) are indispensable in current medical practice, with both serving central venous access needs. They are used for infusion therapy, exchange therapy, and hemodynamic monitoring. The central venous system includes the pulmonary arteries, right heart, superior vena cava (SVC), inferior vena cava (IVC), and brachiocephalic, subclavian, and iliac veins. It should be noted that although these vessels and many other small veins are considered central, they are not necessarily appropriate locations for venous catheter tips. In most cases, the desired position for a CVC tip is in the SVC or right atrium.


Present-day venous access devices are available in a wide variety of sizes, forms, and configurations designed to meet specific needs. It is important to be familiar with the range of venous access devices presently available on the market and the features that affect their selection.



Indications


There are three main indications for temporary CVC insertion: infusion therapy, exchange therapy, and hemodynamic monitoring. Although many CVCs can be used for phlebotomy, this use alone is rarely an indication for insertion.


PICCs are small-bore catheters placed through a peripheral arm or leg vein into the central veins. Midline catheters are shorter than PICCs and typically terminate in the axillary vein. Nontunneled CVCs are inserted more proximal to the central venous system in the internal jugular (IJ), subclavian, or femoral veins.


Indications for placement of a PICC or nontunneled CVC for infusion therapy include (1) rapid infusion of fluids or blood products to maintain hemodynamic stability, (2) infusion of vesicant solutions such as chemotherapeutic, cytotoxic, or inotropic medications or infusates with pH less than 5 or above 9, more than 500-600 mOsm, more than 10% dextrose, or more than 5% amino acids, (3) total parenteral nutrition, (4) active infection that prevents placement of a more permanent device, and (5) coagulopathy that prevents placement of a more permanent device.1-3


Indications for placement of a nontunneled CVC for exchange therapy (hemodialysis and apheresis) include (1) management of acute volume overload not responsive to other medical therapy, (2) management of severe acute electrolyte disorders, (3) management of acute hyperviscosity disorders, (4) short-term apheresis/hemodialysis treatment, (5) stem cell harvesting, (6) active infection that prevents placement of a more permanent device, and (7) coagulopathy that prevents placement of a more permanent device. Owing to small lumen size and low flow rates, current PICC technology does not permit exchange therapy or hemodialysis.


Indications for hemodynamic monitoring are usually encountered in patients in the intensive care unit (ICU). Nontunneled CVCs traditionally serve this function, but PICCs may be used with some limitation based on caliber. These catheters are most commonly inserted at the bedside in the ICU setting.


Catheter choice should be made with expected length of treatment in mind. For short-term access (<2-4 weeks) for infusion, monitoring, or exchange therapy, a PICC or small-bore nontunneled CVC would be indicated. Some studies have reported PICCs functioning for longer than 1 year, and some anecdotal reports have noted functioning PICCs that have been present for longer than 2 years.4-6 However, such reports represent the exception rather than the rule.


For long-term access (>2-4 weeks) a tunneled catheter or implantable port may be indicated. A selection algorithm for choosing among PICCs, nontunneled CVCs, tunneled CVCs, and ports is provided in Figure 118-1.



PICCs have many advantages. They are safe and easy to place, prevent the need for frequent venipuncture, allow easy care and access for inpatients and outpatients, and they are usually well tolerated by patients. Unlike tunneled catheters and ports that require conscious sedation, PICCs and nontunneled CVCs can be placed without sedation with little patient discomfort. They are also easy to remove or exchange in the event of malfunction or infection.


Bedside ultrasound-guided PICC placement by skilled nurses is becoming the standard at many institutions, saving all but the most challenging of patients the time and cost of a trip to the interventional suite. At our institution, only PICCs that cannot be advanced to the cavoatrial junction or the very difficult-to-access patients come to interventional radiology for placement under fluoroscopic guidance.


Nontunneled CVCs have similar properties to PICCs, with the advantage of accommodating large-bore catheters in the larger IJ, subclavian, and femoral veins. The major disadvantage of nontunneled CVCs is the high rate of catheter-related bloodstream infections. In fact, nontunneled CVCs account for the majority of catheter-related bloodstream infections in the United States.


Indications for pediatric PICCs may include the need for venous access of 6 days or more or the need to administer vesicants or other infusates requiring dilution in the central venous system.3 Early PICC placement may spare patients numerous venipunctures. Selection criteria for catheter placement in pediatrics are otherwise similar to adults:




Contraindications


There are very few strict contraindications to PICC and nontunneled CVC placement. These catheters can usually be placed safely regardless of existing coagulopathy or thrombocytopenia. Unlike with tunneled CVCs and ports, active infection or bacteremia does not contraindicate placement. Allergic reactions to contrast material and elevated serum creatinine are relative contraindications to placement under venographic guidance with iodinated contrast agents. However, ultrasound guidance or use of alternative contrast agents such as carbon dioxide gas or gadolinium negates this contraindication. PICCs should not be placed on the same side as a previous mastectomy or axillary lymph node dissection, in a paretic extremity, or in the location of focal infection, burn, or radiation injury.


PICC placement may be precluded in patients in whom a suitable peripheral vein cannot be identified. Central venous thrombosis or occlusion also poses a relative contraindication. Occasionally a guidewire can be used to traverse the thrombosed vein, or access to the central veins can be achieved through collaterals, thus permitting central venous placement of the catheter tip. When this fails, PICCs may be positioned peripheral to the occluded central veins, thereby resulting in subclavian or axillary placement of the catheter tip. This position may be adequate provided fluids to be administered are not hyperosmolar or vesicant fluids. It has been shown that PICCs placed in a noncentral vein can provide reliable safe intravenous access for administration of many medications for up to 2 weeks’ duration.7


Placement of a PICC is contraindicated in any person undergoing hemodialysis or in whom hemodialysis is anticipated, including patients with renal transplants. PICCs are associated with a significant rate of peripheral venous thrombosis.8 To preserve peripheral veins for future hemodialysis access, the National Kidney Foundation Kidney Disease Outcomes Quality Initiative (NKF KDOQI) advises against placement of PICCs in this patient population.9,10



Equipment


Catheter Types


Multiple catheter designs with varying catheter materials (silicone and polyurethane), catheter diameters, and number of lumina are available commercially. Catheters are made with three basic tip configurations: end hole, staggered tip, and valve tipped:



• End-hole catheters are the most common catheter design, with all lumina opening within close proximity of the catheter tip. These devices may be trimmed at the tip to achieve an appropriate length.


• Staggered-tip dual-lumen catheters are specifically designed for therapies that require simultaneous rapid aspiration and infusion with limited mixing (hemodialysis and apheresis). These devices should not be trimmed, so their staggered-tip configuration is maintained.


• Valve-tipped catheters have a specially designed slitlike two-way valve at the catheter tip that is closed in the resting state. The valve opens inward with aspiration and outward for infusion, with the potential advantage of not requiring routine heparinization to prevent catheter thrombosis. The Groshong catheter (C.R. Bard Access Systems Inc., Salt Lake City, Utah) is a valve-tipped catheter. Valve-tipped catheters cannot be trimmed at the tip, but they have a removable external connection that allows the back end to be trimmed for adjustment of length. The Vaxcel catheter with pressure activated safety valve (PASV) (Boston Scientific Corp., Natick, Mass.) incorporates a valve into the hub of the catheter, allowing the tip to be trimmed. PASV catheters have a lower recorded rate of infection, thrombosis, and phlebitis compared to distal valve-tipped catheters.11-13


Standard PICC technology does not allow for high-pressure power injection, but high-pressure injectable catheters are now available. Typically constructed of polyurethane, they usually allow injection up to a maximum of 300 psi and 5 mL/s. Maximum allowable flow rates may vary for individual catheters. High-pressure injectable catheters are most beneficial to patients requiring power injected contrast enhanced computed tomography (CT) studies.



Procedural Supplies


Required supplies for PICC and nontunneled IJ, subclavian, and femoral CVC placement are listed in Table 118-1.



Ultrasound-guided placement is best performed using a 7.5 to 9 MHz probe. A needle guide attached to the ultrasound probe is optional but makes seeing the needle tip puncture the vessel easier.


When placed at the bedside, tip locator devices increase the accuracy of placement. Some examples of these devices are the Navigator Bionavigation System (Medcomp Inc., Harleysville, Pa.) and Sherlock Tip Positioning System (TPS) (C.R. Bard Access Systems). They use an electronic device external to the patient to detect the catheter tip position or tip direction. These systems are not intended to replace appropriate preinsertion measurements or chest radiographic confirmation of tip location.


Accuracy of bedside placement is also increased using electrocardiogram (ECG)-assisted techniques and is being used in lieu of radiographic tip verification.14 Traditional bedside ECG monitors can be used, but dedicated systems are now coming to market to emphasize this technique. At our institution, we use the Sapiens Tip Confirmation System (TCS) (C.R. Bard Access Systems) that uses external ECG electrodes to detect intravascular ECG P-wave changes as the catheter approaches the cavoatrial junction.



Technique


Anatomy and Approach


The preferred location for PICC placement is in the nondominant arm. Placement above the antecubital fossa is preferred and may lower the risk of phlebitis. The order of preference is the basilic, brachial, cephalic, then median cubital vein. The preferred location for nontunneled CVC placement in order of preference is the right IJ, left IJ, subclavian, then femoral vein. Anatomic reference is provided in Figure 118-2.










Technical Aspects


Ultrasound-Guided Placement of a Peripherally Inserted Central Catheter


The arm is positioned at 45 to 90 degrees at the patient’s side on an arm board with the palm up. An appropriate compressible vein should be identified with a tourniquet applied to the shoulder.


The appropriate length of catheter should be calculated before sterile prep and venipuncture. This is critical in the absence of fluoroscopy. The desired tip position is in the distal third of the SVC or at the cavoatrial junction. Measurements are taken from the venipuncture site to the ipsilateral axillary crease to the right sternoclavicular joint and inferiorly to the third intercostal space at the right parasternal border (Fig. 118-3). Lower extremity PICCs are measured from the venipuncture site along the course of the vein to the right of the umbilicus to the xiphoid. Adding the estimated depth of subcutaneous fat to the measurement will increase accuracy. When approaching from the left, adding 1 to 2 cm may increase accuracy as well, owing to catheter flexibility as it courses from left to right in the left brachiocephalic vein. Evaluating a chest radiograph prior to measurement may also help judge the tortuosity of the venous system. Lum’s CVC Measurement guide provides an estimated catheter length based on patient height (Table 118-2).



TABLE 118-2


Lum’s Central Venous Catheter Measurement Guide


















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Dec 23, 2015 | Posted by in INTERVENTIONAL RADIOLOGY | Comments Off on Peripherally Inserted Central Catheters and Nontunneled Central Venous Catheters
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Height (in) R. PICC (cm) L. PICC (cm) R. JC (cm) L. SC (cm) R. SC (cm) Height (cm)
4 ft 8 in 42.5 46.5 13.0