PICCs have many advantages over the other CVADs. Firstly, they eliminate the mechanical complications associated with CVC placement, particularly pneumothorax (Bodenham et al. [43], Dougherty [123], Gallieni et al. [164]). Secondly, PICCs have been shown to be associated with a reduction in catheter sepsis. This may be related to the temperature of the skin; it has been reported that peripheral sites rarely have more than 50–100 colony‐forming units (cfu) of bacteria per 10 cm² of skin compared with 1000–10,000 cfu/cm² on the neck and chest (Carlson [62], Moureau and Gabriel [333], Mussa [341]). Thirdly, PICCs are easy to use for both staff and patients (Dougherty [123], Mussa [341]) and they also help to preserve peripheral veins (Gabriel [159], Mussa [341], Oakley et al. [361]). They have been shown to cause less discomfort than other central venous access devices and provide a reliable form of access (Costa and Ferguson [90], Oakley et al. [361], Mussa [341]). They are also cost‐effective when compared with other long‐term and short‐term catheters and can be inserted at the bedside (Mussa [341], Snelling et al. [419], Wilkes [472]). With proper care and maintenance, PICCs may last for up to a year, without changing the entry site and with minimal risk of complications (Mussa [341]).

Disadvantages of PICCs include an increased need for self‐care, potentially increased difficulty of blood withdrawal with catheters smaller than 4 Fr, and increased chance of occlusion (Dougherty [123], Molloy et al. [321]). Another issue can be flow rate: the diameter of PICCs ordinarily ranges from 3 to 6 Fr, whereas the diameter of other CVCs ranges from 5 to 12 Fr, which explains PICCs’ lower flow rate. However, new CT‐rated technology and newer PICC materials allow higher flow rates, and high‐density solutions (blood, nutritional solutions and/or contrast media) can safely be delivered via PICCs using an infusion pump (Mussa [341]). A further problem is that over time, multiple insertions can cause venous scarring and decrease the ability to reuse the site (Wilkes [472]). It has also been found that compared with skin‐tunnelled catheters in patients with gastrointestinal cancers, the advantages of a PICC decrease significantly if treatment lasts longer than 120 days (Snelling et al. [419]). PICCs should not be considered as a last resort but introduced early in treatment (Blackburn [40], Chopra et al. [77], Moureau and Chopra [330], Springhouse [426]).

Ultrasound guidance aids the clinician in vein identification, assessment and insertion while reducing the risk of complications and stress to patients (Moureau [329]). Venous assessment and selection play key roles in the successful insertion of a PICC, along with correct positioning of the patient and careful measurement of the patient and the device. To obtain the correct measurement of the length of catheter to be inserted based on anatomical landmarks, one option is to use a tape measure and with the patient's arm at a 90° angle to their torso, measure from the selected point for venepuncture to the axilla, and then measure the total distance across the clavicle and down to the intercostal space. Alternatively, Lum ([281]) has developed a formula‐based measurement guide based on the patient's height, which provides a more accurate way to achieve optimal tip placement (Dougherty [123]) (Box 17.7). Arm adduction and bending can influence PICC depth and movement (Connolly et al. [84]). Another simple option is measuring the distance from the selected venepuncture site to the sternoclavicular notch, and then adding the result to a standard value of 10 cm (in right arm insertions) or 15 cm (in left arm insertions). However, these methods, although useful and included in the insertion protocols of most working groups, remain merely predictive and do not give any information about the actual tip location (La Greca [256]).

The catheter tip position may be checked during the procedure, after the procedure or both. Anteroposterior chest X‐ray film continues to be the gold standard method for checking tip position after insertion. However, checking the tip position during catheter insertion is preferable as it avoids repositioning the device and also provides accuracy regarding the exact tip position (La Greca [256], Pittiruti et al. [375]).

Catheter tip position can be checked during insertion using various methods:

Among these intraprocedural methods, fluoroscopy remains the gold standard but it has cost implications and its use may be limited due to logistical issues. ECG‐based tip verification systems offer a safe, accurate, cheap and universally applicable alternative (La Greca [256], Oliver and Jones [364], [365], Pittiruti et al. [375]). The ECG method uses the catheter itself as an intravascular (intracavitary) electrode, which replaces the ‘red’ or ‘right shoulder’ electrode (lead II in a bipolar three‐lead ECG according to the classical Einthoven triangle) of a standard surface ECG (see Chapter c14: Observations for further information on ECG types and lead placement). When the ECG is connected to the intravascular electrode (using either a guidewire/stylet or a saline adapter), the reading of electrode II will show a P wave whose shape and height will change while the catheter is advanced from the peripheral venous system towards the heart. As the catheter tip approaches the sinoatrial node at the cavo‐atrial junction, the P wave starts to elevate, reaching its maximum height at the cavo‐atrial junction. When the tip passes through into the right atrium, the P wave starts to invert, indicating that the catheter tip is in too far. The ideal position for the catheter tip is where the ECG reading shows ‘maximal P’ or where the P wave is at its maximum height without any inversion or negative deflection (La Greca [256], Pittiruti et al. [375]). Changes in the P wave as the catheter tip advances are shown in Figure 17.28.

The accuracy of this method has been proven in numerous international studies (Barton [19], Feng et al. [145], La Greca [255], Moureau et al. [331], Oliver and Jones [364], [365], Pittiruti et al. [375]) and new dedicated ECG tip position devices have been introduced to clinical practice. The combination of the ECG method with a navigation system is now recommended (NICE [352]). Navigation systems are mainly based on electromagnetic tracking of the catheter tip. The catheter tip is assembled with a magnetic‐tip stylet, which can be located with a magnetic sensor placed on the patient's chest surface, either fixed on the chest area or hand‐held by the operator. This allows the catheter tip to be followed as it is progressing through the venous system by a virtual image on a specific screen, using a visual or acoustic alert on the sensor surface, or both (La Greca [256]).