In preterm and sick full-term neonates safe intravenous (IV) access is vital for providing nutrition, medication, fluids, blood and blood products (Rocha et al, 2017). This article provides useful practice advice around using the modified Seldinger technique (MST) for neonatal peripherally inserted central catheter (PICC) insertions. Paying due attention to evidence-based practice and learning from other practitioners can reduce the inherent and potentially avoidable risks associated with the use of PICCs and thus increase patient safety and improve the patient experience.
Choosing a suitable device
There is considerable commercial choice of IV vascular access device (VAD) and consequently it is important to develop clear guidelines on device selection to ensure optimal clinical and economic use (Hugill, 2016). Decisions about which IV route (peripheral or central vein) and device to use are informed by patient and therapy factors such as weight, access (difficulty), duration of therapy and infusion characteristics. Figure 1 provides one example of a decisional flow chart that could be used to inform VAD selection. Its design is based on international standards (Mason-Wyckoff and Sharpe, 2015; Gorski et al, 2016) and local contexts such as product compatibility, hospital purchasing decisions and practitioner consensus.
Accessing the central venous circulation using surgically implanted or tunnelled devices is generally restricted to those infants requiring specialised or very long-term care and consequently less frequently encountered in practice (Hugill, 2016). In contrast, IV central lines inserted by accessing the peripheral circulation are a common feature of neonatal practice. These lines, of various design, material and performance (de Lutio, 2014) are usually referred to as peripherally inserted central catheters (PICCs). However, Barone and Pittiruti (2019) advocated the term ‘epicutaneo-cava catheter’ (ECC) to reflect international nomenclature, although this is not firmly established in practice.
In neonates, the blood vessels of the umbilical stump can also be used to access the central circulation (umbilical venous catheter (UVC) and umbilical arterial catheter (UAC)), though those are not considered to be PICCs. Umbilical catheters for fluid infusion are the most frequent route to access the central circulation, particularly in the early hours after birth (Arnts et al, 2014). Their use is associated with a number of potentially serious risks and complications (Hugill, 2016). These include lower limb ischaemia, hepatic necrosis, renal artery occlusion and central-line associated bloodstream infection (CLABSI) with prolonged insertion time (Arnts et al, 2014). Consequently, umbilical catheters are only considered suitable for short-term use of between 2 and 7 days, although consensus about the exact duration of use is lacking. Table 1 highlights the typical indications for which PICCS are used in neonatal intensive care units (NICUs). Regardless of what devices are chosen for use, it is essential that users acquaint themselves with the design features, manufacturing, performance and handling characteristics of each item, as unfamiliarity can reduce dexterity and increase the risk of complications.
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Sources: Mason-Wyckoff and Sharpe, 2015; Ainsworth and McGuire, 2016; Gorski et al, 2016
PICC insertion and use risks
Table 2 summarises the common and less commonly encountered complications associated with PICCs. All VADs are associated with complications, these can broadly be categorised as therapy, patient, user or device related, although these factors are often interrelated. The use of standardised evidence-based insertion, maintenance and removal care-bundles is known to reduce the incidence of complications, particularly infection related (Arnts et al, 2015; Gorski et al, 2016). PICCs must be removed when irredeemable complications arise, or when sepsis, bacteraemia, or fungal infection is suspected (Mason-Wyckoff and Sharpe 2015). Evidence suggests that the risk of CLABSI increases the longer a PICC remains in situ (Sanderson et al, 2017). Some authors (eg Sengupta et al, 2010; Milstone et al, 2013) have suggested that, to reduce this risk, PICCs should be replaced at periodic intervals of between 14 and 35 days. However, further research is required to determine the optimal balance between infection risk, replacement hazards and dwell time. Generally, planned removal occurs when the access is no longer required for therapy. In practice, deciding this can be open for discussion. For example, in practice some colleagues advocate that PICCs used for parenteral nutrition should be removed when infants are fully enterally fed, whereas others promote removal 24 hours after this point or when the infant achieves an agreed enteral calorific intake. This lack of clarity and the absence of specific evidence-based guidance for practice can lead to confusion and debate.
| Risks during insertion | Inability to access or dilate a suitable blood vessel |
| Risks following insertion | Catheter tip migration after procedure: |
Sources: Mason-Wyckoff and Sharpe, 2015; Lloreda-García et al, 2016; Pet et al, 2020
Preparation for insertion
Once a decision is made to insert a PICC, it is then usual and considered good practice to converse with the infant's parents to explain the rationale, merits and risks of the procedure/therapy and obtain their consent. Doing this can help parents to adapt to the NICU environment, gain a greater understanding of their child's illness and express their opinions about the care. Furthermore, these communications can provide a platform to build trust, reduce stress and foster feelings of involvement (Gallagher et al, 2018; Skene et al, 2019).
Newborn infants have an immature skin barrier at birth (Hugill, 2016). Preparing the skin for invasive procedures can be a significant risk factor for serious iatrogenic harm, including chemical burns and poisoning (Loveday et al, 2014; Mason-Wyckoff and Sharpe, 2015; Gorski et al, 2016). Box 1 summarises these concerns.
Insertion techniques
Traditionally, after suitable site preparation and following strict sterile technique, neonatal PICCs have been inserted using the direct introducer with steel split-needle technique (Bueno et al, 2008). Although the needle is sufficiently small to access neonatal peripheral blood vessels, this technique has some limitations. First, there is a risk of catheter damage when splitting the needle, and second, the needle can only facilitate the smaller 1 Fr and not larger 2 Fr (single/double lumen) PICCs. Other methods include the fine-tipped (Uygun, 2016), the Seldinger and MST (Bueno et al, 2008; Arnts et al, 2015; Athikarisamy et al, 2015).
The MST, as adapted for neonates, is minimally invasive but requires mastery of a slightly different technique to other methods. Various commercial kits are available with all the required equipment to conduct this procedure. One approach involves accessing the selected vein with a 24 Ga steel needle then introducing a nitinol guidewire. The needle is then removed over this guidewire leaving it inside the vein. Then a vein-dilator with a peel-away PICC introducer sheath is introduced over the nitinol guidewire. After the vein-dilator/introducer combination is placed inside the vein the nitinol guidewire and vein-dilator can be removed. At this moment only the PICC introducer is inside the vein and the PICC with its internal radiopaque guidewire can be inserted and advanced to the desired position. Once the precalculated depth is obtained the introducer sheath can be safely unpeeled and removed and tip position checked/confirmed using radiography.
The MST has advantages over other techniques; it enables smaller peripheral veins to be used, decreases venous trauma and procedure time (once mastered), increases first attempt success rates and reduces infant stress (Athikarisamy et al, 2015; Mason-Wyckoff and Sharpe, 2015; Rocha et al, 2017). A further useful feature of this technique is the possibility of using the ‘catheter exchange procedure’ (Pettit, 2007). This procedure permits a ‘second chance’ for the insertion of a new catheter within the same vein when complications arise with the first insertion.
Securing after insertion
After insertion and tip position is confirmed, stabilisation and dressing is required. Sometimes bleeding at the site is problematic. In these situations, it is common to apply a topical haemostatic agent and closely observe for 24 hours. After this time and under aseptic conditions, the agent is removed, and the site redressed. However, it is important to recall that all manipulations of the PICC add to the risk of complications such as infection or accidental removal. Mechanical PICC stabilisation devices are widely available (eg StatLock, BD) but recently cyanoacrylate adhesives (eg SecurePortIV, Adhezion) have become popular in practice. Using adhesive enhances securement and seals the insertion site resulting in less catheter damage, fewer accidental removals, control of bleeding without haemostatics and possibly reduces infection (Kleidon et al, 2017; Ullman et al, 2017).
Overcoming practical challenges
Due to their small size, often weighing less than 1 kg, immature skin and vascular anatomy and physiology, preterm infants pose unique challenges in obtaining and safely using vascular access. Planning and anticipating for vascular access needs in neonates using decisional flow charts such as that shown in Figure 1 is essential to mitigate risks and ensure effective therapy. Damage to peripheral veins caused by repeated peripheral IV device insertion attempts presents challenges for successful PICC insertion. To prevent this, having a dedicated multi-professional team working to evidence-based guidelines, limiting the number of attempts by a practitioner and for an individual infant, and reserving certain blood vessels (eg saphenous) for PICCs alone can help prevent infants becoming characterised as having difficult venous access (Bayoumi et al, 2020).
Manufacturing defects are rare but nonetheless it is advisable, and recommended by the manufacturers, to carry out pre-procedural checks. Inspect the patency of the PICC, by flushing, and check that all elements in the insertion kit readily fit together and readily release. Removing the needle over the guidewire often leaves blood particles on the guidewire. This blood can coagulate and make it difficult to advance the vein-dilator/PICC introducer sheath over the guidewire. To overcome this, carefully remove the blood using gauze by moving slowly down the guidewire in the direction of the vein to avoid accidentally removing the guidewire.
The relatively small puncture hole in the skin made by the needle can make it difficult for the vein-dilator to overcome skin resistance during insertion through the skin into the vein. If the insertion angle is too steep the vein dilator will kink, causing the guidewire to kink, making smooth PICC insertion almost impossible. Sometimes a small skin incision reduces skin resistance but, in the authors’ experience, using an insertion angle parallel to the skin with an assistant stretching the skin generally overcomes this problem.
A common error is to attempt to over-rapidly advance the PICC, this can lead to encountering resistance. It is better to advance slowly in small increments. Doing this allows the natural direction of blood flow to direct the tip towards the right atrium, and helps to avoid vasospasm and deviation into non-target blood vessels. If resistance is still met there are several options that might help:
Finally, if a 2 Fr PICC cannot be advanced it is possible to change to a 1 Fr size if appropriate.
A detailed explanation of how to use anatomical/radiological landmarks to predetermine insertion length and assure correct tip placement is beyond the scope of this article. However, optimally the catheter tip should always be visually confirmed to be located on the right side of the vertebrae and in the vena cava (superior/inferior) near the right atrium but outside the cardiac contours (Mason-Wyckoff and Sharpe, 2015). Conventional radiology remains the main method of confirming tip position (Singh et al, 2020). The safety, efficacy and potential benefits of using non-radiological technologies such as ultrasound (eg Song et al, 2018), real-time and post-procedure and intracavity ECG (eg Xiao et al, 2020) for guiding/confirming tip placement are currently under study internationally. Although results are promising, current guidance suggests that these technologies (in neonates) are best considered as complementary to radiological methods (Singh et al, 2020). However, this advice is likely to change as new research evidence is published and practitioners become more experienced with use.
Unfortunately, sometimes the PICC course deviates from its intended route; partially withdrawing, pausing then re-advancing, with or without ultrasound guidance to identify the correct passage, is the most common manoeuvre to correct the course of the catheter (Suell et al, 2020). Spencer (2017) described another method, which has been used successfully with both upper and lower limb PICCs. The technique, known as the ‘high-flow-flush technique’ involves flushing the catheter in situ to encourage the tip to align with the dominant venous blood direction (ie towards the direction of the heart) and reposition itself.
On occasions despite regimens of generous pre-flushing prior to insertion, removing the internal PICC guidewire can be problematic. Increased resistance on removal can influence tip location and potentially cause catheter leakage or breakage (Wang et al, 2019). Several things can be tried to decrease resistance during removal. It is helpful to reduce any tension in the guidewire by straightening and untwisting the parts of the PICC still outside the body before attempting to remove the guidewire, this is often all that is required. One novel approach is to use diluted lipid emulsion (1:9 with normal saline) as a lubricant (Vygon, personal correspondence). Although this has been used successfully in practice with particularly intractable removals there are potential safety concerns such as lipid emboli and infection. Further empirical study is required to quantify these risks and until this evidence is available this approach should be restricted to use in research.
It is important to highlight that successful neonatal PICC insertion and use is a team effort involving collaboration between many parties—manufacturers, hospital finance, infection control, pharmacy, nursing, midwifery and clinicians with the informed involvement of parents—and not due to the dexterity of an individual practitioner. Nonetheless, those involved in inserting PICCs must receive hands-on training in the use of their selected device and possess advanced understanding of neonatal vascular anatomy and physiology, anatomical landmarks, blood flow patterns and vessel diameters for example in order to be successful (de Lutio, 2014; Gorski et al, 2016; Lloreda-García et al, 2016).
Conclusion
PICCs are used extensively within NICUs to access the central venous system. However, practices and practice standards around PICC insertion and aftercare vary. Compared with other VADs, PICCs are generally associated with fewer complications. However, although some of these are relatively benign and easily managed, others can be life threatening. Nurses involved in inserting, aftercare and use of these medical devices need to be cognisant of these risks, their remedy and emerging product innovations. This article has related important elements of the evidence base supporting insertion practices and highlighted practice pointers that can make PICC insertion a better and safer practice for practitioners and infants alike.