The ability to obtain venous access in the inpatient and outpatient setting is one of the most fundamental, yet, crucial components for a large number of diagnostic and therapeutic interventions. It is especially vital for critically ill patients who often require frequent blood sampling, vasoactive medications, rapid fluid resuscitation, prolonged antibiotic administration and various other indications. Venous access can be obtained through conventional peripheral intravenous (IV) lines, midline peripheral catheters, and central venous catheters (CVCs).
Peripherally inserted central catheters (PICCs) are a subset of central venous catheters. They are 50 cm to 60 cm long single, double or triple lumen catheters that are placed in a peripheral arm vein and terminate in the thorax. They can be used for medium-term venous access, which is defined as anywhere between several weeks to 6 months.
Anatomy and Physiology
By definition, a central catheter is a venous access device that ultimately terminates in the superior vena cava (SVC) or right atrium (RA). They can be inserted centrally (centrally inserted venous catheter; CICC) or peripherally (PICC). PICCs are placed through the basilic, brachial, cephalic, or medial cubital vein of the arm.
The right basilic vein is the vein of choice due to its larger size and superficial location. Additionally, it has the straightest route to its destination, as it courses through the axillary vein, then through the subclavian, and finally, settles in the SVC. Other factors that have been thought to make the basilic vein the superior choice for PICC lines are that it has the least number of valves, better hemodilution capabilities and has a shallower angle of insertion compared to other veins.
The median cubital vein usually offers the second best insertion site because it is prominent in the antecubital fossa and courses directly to the basilic vein and onward into the SVC. However, given its location in the antecubital fossa, constant bending at the elbow increase the risk of complications such as mechanical phlebitis.
The cephalic vein is another option for PICC-line placement but, in addition to being smaller than the basilic vein, its course through the upper arm can be very tortuous. PICCs placed through this vein are thought to have a higher incidence of mechanical phlebitis, and its sharp angle of insertion makes it difficult to advance the catheter.
The brachial vein is another option due to its larger size; however, it is smaller and runs deeper than the basilic vein. It also courses close to the brachial artery and median nerve, and therefore, it usually requires ultrasound guidance for access.
The PICC is a reliable and safe method for obtaining central venous access. They are indicated in patients who require venous access for several weeks to months due to their low infection rates. Additionally, they can be managed in inpatient and outpatient settings. Common indications include:
- Patients with limited peripheral access
- Long-term IV medication administration (antibiotics, antifungals)
- Continuous administration of vesicants or drugs that irritate peripheral veins (vasoactive drugs, chemotherapeutic agents)
- Delivery of hyperosmolar solutions or substances with extreme pH (total parenteral nutrition)
- Blood product infusions
- Frequent blood draws
- Patients with coagulation disorders (thrombocytopenia)
- Major anatomic abnormalities in the chest and neck that make central catheter placement difficult
- Rapid infusions
There are essentially no absolute contraindications to central venous catheterization, especially in emergent cases when the above indications are necessary for life-saving interventions. There are, however, several relative contraindications for PICCs. These include:
- Burns, trauma, skin infections, radiation, history of venous thrombosis at insertion site
- Active bacteremia
- Chronic renal failure, end-stage renal disease (veins should be preserved for potential dialysis catheter placement)
- Small diameter of arm veins (smaller than 3 mm to 4 mm)
- Prior mastectomy and lymph node dissection (lymph system is compromised and unable to drain)
- Patient requires crutches (places pressure on veins of the arm)
- Persistent cough, vomiting (increased intrathoracic pressure can lead to catheter malposition, catheter erosion or cardiac tamponade)
PICC lines can differ in size (50 cm to 60 cm), the number of lumens (single to triple), and care and maintenance routines. Additionally, they can be valved or non-valved. Valved catheters prevent backflow of blood into the catheter when the system is open.
Different brands of catheters may have subtle differences in their packaging and equipment. The modified Seldinger technique is by far the most widely used method for PICC placement. Below is a general list of standard equipment when using the modified Seldinger technique:
- Ultrasound and sterile probe sheath cover with ultrasound gel
- Sterile gloves and gown, mask with face shield and hair cover
- Sterile drape and towels
- Skin cleansing solution (chlorhexidine/alcohol)
- Sterile saline flushes
- Tape measure
PICC insertion kit
- PICC catheter
- Needles of varying gauges
- 10 mL syringes
- Small blade
- Local anesthetic (usually lidocaine)
- Suture material
- Sterile dressing kit (typically transparent and semipermeable)
PICCs can be placed by any trained physician, registered nurse, or physician assistant. However, many institutions have dedicated teams of PICC nurses. These specially trained nurses have shown to increase success rates of catheter placement while decreasing complications through consistent proper, sterile technique in a cost-effective manner.
Central venous catheters can be placed surgically or non-surgically, although PICCs are typically placed non-surgically at the bedside using ultrasound guidance. Ultrasound guidance shows considerably improved outcomes. As with any procedure, preparation with is essential, and ensuring that all necessary equipment and materials are present is paramount for successful outcomes.
Sterile technique is especially vital for this procedure to decrease the risk of catheter-related bloodstream infections (CRBSIs). Education of standardized catheter placement, care, maintenance and prevention of infection have been shown to reduce the incidence of CRBSIs drastically.
The entire procedure, including preparation for PICC placement, is outlined in the Technique section below.
As mentioned previously, the Seldinger technique is by far the most commonly used method for placing PICCs. Peel-away cannulas or brake-away needle methods are other options. However, they require large veins to accommodate larger sized needles and introducers, which potentially exposes the patient to increased risk of excessive bleeding. Additionally, peel-away catheters are known to cause air emboli.
Below are the steps for the sterile, modified Seldinger technique:
- Obtain consent from patient or their decision make
- Gather supplies (PREPARATION IS KEY)
- Measure patient's arm circumference; this serves as a reference to determine any arm swelling should it occur due to complications from PICC placement
- Locate which vein will be accessed for line placement; this can be done using ultrasound
- Applying a tourniquet and ensuring that the patient is adequately hydrated can also help in locating veins
- Mark insertion site using a marker or by creating skin indentation using a pen
- Measure length required to advance the catheter to the SVC/right atrial junction.
- This is commonly done by measuring from the site of insertion to the mid-right mid-clavicular line, and down to the third intercostal space. Perform proper hand hygiene
- Cleanse the portion of the upper arm with chlorhexidine/alcohol
- Don mask with face shield and hair cover followed by sterile gown and gloves
- Create sterile field by placing sterile towels and drape
- Anesthetize skin (if necessary)
- Re-identify vein using ultrasound.
- Access vein using needle and syringe until blood is aspirated
- Remove the syringe and advance guide wire through the needle. Remove the needle and confirm wire placement in vein using ultrasound
- Using the scalpel, create small nick at insertion site alongside guide wire to accommodate dilator
- Insert dilator and introducer over the guide wire
- Remove guide wire and dilator, leaving only the introducer in place
- Insert catheter through introducer and advanced to predetermined length
- Remove introducer
- Confirm proper placement of the catheter in atriocaval junction by obtaining chest x-ray before using PICC.
After placement and functionality have been confirmed, appropriate maintenance, which includes the use of stabilization devices, frequent flushing of line with saline and heparin-containing solutions, and sterile dressings replaced at regular intervals, should be employed to minimize complications.
As with any indwelling catheter in the body, there is always the risk of infection. This can result in cellulitis, abscesses, or bacteremia and systemic infections. The most common organisms associated with hospital-acquired CRBSIs (in order of most to least common) are coagulase-negative Staphylococci, Staphylococcus aureus, Enterococci, and Candida.
The cumulative incidence of CRBSIs for PICCs is 1.1 per 1000 PICC-days. However, it is found to be higher in the inpatient setting (2.1 per 1000 PICC-days). This could be because patients managed on an outpatient basis are healthier in general, and their catheter is accessed less frequently. There is still question whether PICCS or centrally inserted venous catheters (CICCs) have lower infection rates. Though past studies have argued for lower infection rates with PICCS among critically ill patients, recent publications, in including a 2016 study comparing 200 PICCs and 200 CICCs, have shown no difference.
Infection rates are higher for PICCs placed in the antecubital fossa compared to those placed in the upper arm (i.e., basilic vein). Other factors that increase the risk of infection are those that are not tunneled and those with multiple lumens.
Prophylactic antibiotics have not been consistently proven to prevent infections, in fact, their use is not recommended. However, devices impregnated with antimicrobial or antiseptic devices have been proposed to reduce the incidence of catheter-related infections. Although it may seem obvious to change catheters to prevent infection routinely, this is not the case for PICCs. In fact, the Centers for Disease Control and Prevention (CDC) recommends against the regular replacement of PICCs to prevent CRBSIs.
Exit-site and tunnel infections, septicemia, fungemia, septic thrombosis, endocarditis, osteomyelitis and sepsis with signs of shock, and/or end-organ dysfunction are all indications for device removal.
PICC malposition is common. They can be misplaced in the jugular vein, brachiocephalic vein, or azygous vein. Causes include vascular abnormalities, a patient’s position during insertion or changes in venous pressure inside the chest if a patient coughs or vomits. When malposition occurs upon insertion, it is referred to a primary malposition.
Migration is a change in the length of catheter extruding from the insertion site. When the catheter tip migrates spontaneously after initial placement in a proper location, it is referred to as secondary malposition. This can occur with high-frequency ventilation, extreme physical activity and rapid infusion/forceful flushing of fluid. Migration interferes the ability to withdrawal blood. However, it can also cause cardiac tamponade via erosion of the catheter through the RA or ventricle. This is a medical emergency and must be addressed immediately.
Catheter malposition and migration can be assessed using chest radiographs as well as by administering contrast die to determine the path of veins. Repositioning can be successfully achieved by trained nurses using simple bedside techniques (i.e., having patient turn head, hold breath). Securing catheters at the insertion site can prevent tip migration.
Another major complication is device malfunction, with anywhere between 10% and 27% of PICCs developing mechanical failure. Catheter “pistoning” in the vein can increase the possibility of phlebitis. They can embolize during placement if sheared by needles or surgical instruments. Fractures of the internal portion of the catheter are also possible, which would possibly require removal through surgeons or interventional radiologists.
Phlebitis and infiltration are complications that occur in 2.2% to 23% of patients with PICCs. It is a result of mechanical damage from the catheter itself or chemical irritation (medications). Phlebitis may occur within the first week after insertion and can be treated using non-steroidal anti-inflammatory agents or with the warm compress. Removal of the catheter is not necessary. If chemical irritation causes it, diluting medications or administering them at a lower rate can decrease inflammation.
Air emboli are extremely uncommon with PICCs. However, they can occur. They are caused by an inability to maintain a closed system between the catheter and vasculature. Catheter damage, line disconnection, or lack of occlusive dressings are all capable of disrupting this closed system. Other causes of air emboli are lack of line flushing or improper flushing technique. Like a cardiac tamponade, this is a medical emergency and requires immediate attention.
Arrhythmias are caused by the catheter tip being positioned “too low” into the RA or ventricle due to primary or secondary malpositioning, resulting in conduction abnormalities. It can be easily corrected by withdrawing catheter to its correct position and securing it to prevent migration.
Catheter occlusion can occur as a result thrombotic and non-thrombotic causes.
A blood clot is the most common cause of catheter occlusions. Thrombosis can occur in any one of the veins catheterized (including the SVC) or the catheter itself. The positioning of the catheter tip high in the SVC has an increased risk of thrombosis (up to 78%) compared to placement in the distal SVC/RA (16%). Septicemia also greatly increases the incidence of thrombosis. In fact, one study reported a relative risk of 17 for developing clinical signs of thrombosis after an episode of central venous catheter-related infection. Other risk factors include more than one insertion attempt, vessel wall damage from previous catheter placement, ovarian cancer, left-sided insertion, and triple lumen catheters.
Other causes of occlusion can be non-thrombotic. Malpositioning, such as catheter abutment against the wall of a vessel or kinking, can cause occlusion. Additionally, drug precipitation among incompatible medications/solutions can block the catheter. Common drugs known to precipitate are etoposide, calcium, diazepam, phenytoin, heparin and total parenteral nutrition.
It is important to properly flush catheters before and after blood collections and medication administration. Ensuring drug and solution compatibility can also prevent precipitation of medications. Finally, repositioning a patient or the catheter itself can resolve occlusions from catheter kinking or abutment.
Central venous access devices have been the safest and most efficient method for long-term medication and fluid administration in hospitalized patients since the 1970s, especially those in intensive care units (ICU). Its scope of usage has since extended to into the outpatient setting. In fact, PICCs are particularly appropriate for those who require regular outpatient-based treatments.
PICCs have several advantages over other central catheters. They provide medium-term venous access for several weeks up to 6 months, whereas non-tunneled CICCs typically use for several days. They much more easily accessible due to their peripheral exit site and are capable of delivering the same caustic medications and fluids at similar flow rates compared to other central catheters. They can be easily placed and removed at the bedside by nursing staff whereas other central catheters, such as tunneled catheters and central ports, must be placed surgically. PICCs can also be used in thrombocytopenic patients (platelet count less than 50,000/mm), whereas central ports have increased the risk of hematoma with recurrent needle punctures required for access.
PICCs do have some limitations, however. They are a usually smaller bore, which is less useful for frequent blood draws (though still possible using a syringe). Additionally, for patients requiring daily access for stem cell or blood product administration, surgically inserted central catheters are preferred. Finally, tunneled central catheters and implantable ports can be used for longer than six months, whereas PICCs are not indicated for that length of time (although they have been known to be functional for more than 300 days).
In conclusion, PICCs are an excellent option for various diagnostic and therapeutic interventions and offer clinicians and nurses a safe and effective option for central access. They have been shown to be more cost-effective, have lower complication rates than CICCs and continue to gain popularity in the intensive care setting.
Enhancing Healthcare Team Outcomes
PICC lines are much more effective for long-term intravenous use. They are used in almost every department in the hospital and also outside the hospital. But in order to look after a PICC line, nursing skills are essential. The longevity of a PICC line is highly dependent on the care. Every hospital has its own protocol on how PICC lines should be looked after. In some hospitals, there are PICC line nurses devoted to the care so that there is uniformity in cleaning and dressing. Further, there is usually a team of healthcare professionals including nurses which assess PICC lines in hospitals and in outpatients for infection, dislodgement, and leakage. Finally, nurses also play a vital role in educating other nurses on the usage of PICC lines and the importance of aseptic techniques. Only through such an approach can complications associated with PICC lines be minimized. (Level V)
Overall PICC lines serve a useful purpose in more than 95% of patients. The duration of PICC lines may be from 4 weeks to 6 months. Over the long run, PICC lines do develop complications like infection, thrombosis and catheter blockage, but their benefits far outweigh these complications. (Level III)