Peripheral intravenous venous (PIV) access is the mainstay of vascular access during pediatric hospital admissions and is nearly ubiquitous in inpatients. PIV access is often the best option for hydration, medication administration, and blood sampling. It is technically more straightforward and safer than central access and can usually be performed at the bedside without anesthesia or sedation.

Although PIV access is often obtained by skilled members of the patient care team such as nurses and anesthesia staff, it can be quite challenging in children. Consequently, the pediatric surgeon may be called upon if others are unable to obtain access. Veins in children are small in caliber and often difficult to see and feel, especially if the patient is dehydrated. It is therefore essential to have knowledge of the anatomic locations amenable to PIV insertions and the availability of devices that can aid access.

The primary venous anatomy for PIV insertion is pictured in Fig. 7.1 . The scalp site is limited to neonates. The external jugular vein, though of adequate size and visibility, is frequently difficult to access at the bedside given its mobility and proximity to major structures. The superficial veins of the arm and dorsal hand/wrist are good targets for access, but care must be taken to avoid crossing the antecubital fossa with the catheter unless the arm is immobilized. In the lower extremity, the greater saphenous vein is often a good target, especially anterior to the medial malleolus. This is best visualized with the foot held in plantarflexion. In an emergency when access cannot be acquired, the distal saphenous vein is also a good target for peripheral cutdown—although intraosseous (IO) access should be considered first, since it is usually faster. The cutdown is performed via a small transverse incision medial and superior to the medial malleolus, with suture ligature and direct venipuncture.

Common sites for peripheral IV insertion.

From Church JT, Jarboe MD. Vascular access in the pediatric population. Surg Clin North Am . 2017;97(1):113–128.

Technology can be employed to aid peripheral intravenous access. Ultrasound is exceedingly helpful in visualizing vascular anatomy ( Fig. 7.2 ). It can distinguish between arterial and venous structures based on compressibility, pulsatility, and the use of color flow Doppler. Studies have demonstrated that ultrasound in PIV access reduces the required attempts and improves accuracy. ^, Ultrasound technology and availability are constantly improving. Other technological advancements that aid PIV access include infrared-based vein finders. This modality improves vein visibility, thereby increasing accuracy and decreasing the pain associated with access. ^,

Ultrasound image of upper arm anatomy.

From Surg Clin North Am . 2017;97(1):113–128.

Neonates are often managed with catheters placed in either the umbilical vein or one of the umbilical arteries. They can be used for monitoring central venous or arterial pressure, blood sampling, fluid resuscitation, medication administration, and PN. To minimize infectious complications, umbilical vein catheters (UVCs) are usually removed after a maximum of 14 days. ^, These catheters are typically placed by neonatal nurse practitioners or neonatologists and require dissection of the umbilical cord stump within a few hours of birth. It is possible for the pediatric surgeon to cannulate the umbilical vessels after the umbilical stump has undergone early desiccation. A small vertical skin incision is made above or below the umbilical stump to access the umbilical vein or artery, respectively. Once the fascia is incised, the appropriate vessel is identified, isolated, and cannulated. The tip of the UVC should be positioned at the junction of the inferior vena cava (IVC) and the right atrium (RA). The xiphisternum is a good landmark for the RA/IVC junction. On the chest radiograph, the tip of the UVC should be at or above the level of the diaphragm. Electrocardiography and ultrasonography have been shown to be more accurate than plain radiography in accurately positioning the tip. The tip of the umbilical artery catheter (UAC) is best positioned between the sixth and tenth thoracic vertebrae above the celiac axis. Various calculations have been proposed to estimate the correct length of the catheter before insertion based on the weight and other biometric measures of the infant. ^, The “high” position just described has been associated with a low incidence of clinically significant aortic thrombosis without any increase in other adverse sequelae. ^, These UVCs have been associated with various complications. In addition to tip migration, sepsis and vessel thrombosis can occur. Additionally, UVCs have been associated with perforation of the IVC, extravasation into the peritoneal cavity, and portal vein thrombosis. UACs are associated with aortic injuries, thromboembolism of the aortic branches, aneurysms of the iliac artery or the aorta, paraplegia, and gluteal ischemia with possible necrosis. The pooled rates of bloodstream infections associated with umbilical catheters and central venous catheters (CVCs) in level III neonatal intensive care units have improved in recent years. ^,

Multiple studies have established the safety and effectiveness of IO access for infusion of fluids and medications in children, including neonates. ^, IO access has also been shown to be faster than PIV access and safer than an emergency CVC.

Bone marrow consists of a rich lattice network of vessels. Whereas peripheral veins collapse in patients in shock, the vascular spaces in bone marrow do not. The bioavailability of resuscitative drugs administered through IO access has been well established and shown to be better than that for drugs administered through an endotracheal tube. ^, The current Pediatric Advanced Life Support recommendation is to establish IO access promptly in neonates if PIV access cannot be attained rapidly, and in children of all ages who urgently need intravenous drugs or fluids. In children, the long bones of the lower extremities are used preferentially for IO placement. The proximal tibia is the most common site, followed by the distal femur. With full sterile precautions, a needle designed for bone marrow aspiration is advanced through the cortical bone to access the bone marrow. In an infant, a spinal needle may be used, but in an older child, a generic bone marrow needle or a purpose-designed IO needle such as the widely used Jamshidi needle (Cardinal Health, McGraw Park, IL) is used. ^,

The best site is the anteromedial flat surface of the tibia 1–3 cm below the tibial tuberosity. A small skin incision is made with the tip of a pointed scalpel or a large-bore hypodermic needle. The IO needle is pointed posteriorly and angled slightly caudad. It is then advanced through the cortical bone using a screwing and unscrewing motion with constant pressure. Once the needle penetrates the outer cortex, a sudden “give” is felt. The needle is held in this position, and the obturator is removed. A syringe is attached, and bone marrow is aspirated to confirm correct placement. The IO needle is stabilized with a dressing. The distal femur location is accessed by placing the needle 1–3 cm above the patella and angled slightly cranially to avoid the growth plate.

Contraindications to IO placement include injury or suspected injury to the bone or soft tissue overlying the placement site. Mechanical devices such as the Bone Injection Gun (BIG, Wasimed, Caesarea, Israel), FAST1 System (Pyng Medical Corporation, Vancouver, Canada), and EZ-IO (Vidacare, San Antonio, TX) have helped expand the use of IO access. ^, The first two are spring-loaded devices. The FAST1 System is designed for sternal use in adults. The EZ-IO is a power drill–assisted device that makes IO placement easier in older children and adults.

Early concerns about potential adverse effects on the growth plates of the long bones used for IO access have been allayed by animal studies. The overall complication rate is estimated to be about 1%. Extravasation of fluid is the most common adverse event. Compartment syndrome, osteomyelitis, skin and soft tissue infection, bone fractures, and fat embolism, although rare, have also been reported. ^, IO access is usually discontinued once the patient is stabilized and rehydrated, and more durable peripheral or central venous access is obtained.

Central access is required for several medications and fluids, including many vasoactive drugs, cytotoxic medications (e.g., most chemotherapy), and hyperosmolar fluids such as for PN. Additionally, central access may be indicated when peripheral access cannot be obtained, which is a common scenario in the pediatric population. Depending on the medical therapy required, central venous access can be approached many ways. Since the pediatric surgeon may not be the primary provider using the catheter, clear communication between the primary physician and surgeon is essential to ensure the patient undergoes the correct procedure with the correct catheter type and number of lumens.

Central venous access comprises several types, as summarized in Table 7.1 . The intended duration and frequency of use are the primary determinants in CVC selection. Central venous lines (CVLs) intended for long-term use and needed after hospital discharge are often tunneled under the skin to add stability and prevent infection. Cuffed CVLs, such as the Broviac (Becton, Dickinson and Company, Franklin Lakes, NJ) and Hickman catheters (Becton, Dickinson and Company, Franklin Lakes, NJ), exit the skin so they can be easily accessed, making them ideal for continuous use (e.g., daily PN). Ports, on the other hand, remain completely subcutaneous and require needle puncturing of the skin; however, the risks of infection and line damage are reduced. Ports are for long-term, intermittent use (e.g., chemotherapeutic drugs). Both types of tunneled CVLs may be single lumen or multilumen depending on the intended medication administration plan.

Percutaneous, nontunneled CVLs are intended for acute use during hospital admissions. Similarly, acute hemodialysis lines (noncuffed) allow for hemodialysis or plasmapheresis in the hospital setting. However, they are not intended for long-term outpatient use. Long-term durable access is best provided by an arteriovenous fistula (AVF) or a graft, or if these are not available, by a cuffed hemodialysis catheter.

PICCs (peripherally inserted central catheters) are more versatile. As the name implies, they are long catheters with percutaneous entry into a peripheral vein with the tip in the central venous compartment. Their long length and small diameter do not permit high flow rates, and they are not suitable for acute, high-volume resuscitations. However, they provide more stability and comfort than most percutaneous CVLs and can be used in outpatient settings for prolonged periods, sometimes as long as several months.

Preoperatively, the surgeon must also decide on the access site for the CVL. Many anatomic locations can be chosen, including the following veins: external jugular or internal jugular (IJ), facial, subclavian, and femoral. The IJ, subclavian, and femoral veins are the most common and well defined. The advantages and disadvantages of each location are outlined in Table 7.2 .

Most venous access in children can be obtained with a 21- or 22-gauge needle (in premature neonates, a 24-gauge angiocath is often used). Smaller needles preclude the passage of all but the smallest guidewires. Twenty-one-gauge or smaller needles are considered micropuncture needles and are unlikely to inadvertently injure structures. Larger needles present unnecessary risks of damage to nearby structures and the target vein itself. A 22-gauge needle will allow the passage of a 0.018 inch coaxial wire. We prefer the Cope nitinol mandril 0.018 inch wire guide (Cook Medical, Bloomington, IN). The flexible tip reduces risk of vascular damage from the wire, while the stiff shaft provides backbone for placement of dilators and catheters.

In general, J- or C-wires should be avoided in pediatric patients. While these wires are intended to curl to form a blunt, safe leading tip while advancing the wire in adult patients, the radius of curvature is often too large for the size of the pediatric patient’s veins, especially those of neonates. Formation of this shape at the tip of the wire often ejects the wire and needle from the vascular lumen, losing access and causing hematoma formation.

Once the vessel has been accessed by the 0.018 inch wire, it can be exchanged for a larger, 0.035 inch guidewire using a 3–4 Fr dilator (3 Fr dilator seated within a 4 Fr dilator) if the vessel size permits. These dilators are included with the micropuncture introducer set (Cook Medical). A 0.035 inch wire allows for the passage of larger dilators and can provide a stiffer backbone for easier and safer dilation. Depending on the catheter selected, its placement can be directly over the wire (Seldinger technique), or a peel-away sheath can be placed through which the catheter can be inserted into the vessel (modified Seldinger technique). Of note, in the very small vessels of the neonate, catheters are made to go over smaller wires such as 0.018 inch and 0.010 inch, so that exchange to a 0.035 inch wire is not necessary.

In the past, central venous access was obtained using anatomic landmarks. However, the introduction of ultrasound guidance has made the procedures safer and easier, particularly in children. ^, A high frequency (7.5–20 MHz) linear transducer is used, as it provides the best spatial resolution.

It is helpful to establish the left-right orientation of the ultrasound prior to attempting access (for example, the left side of the probe seen on the left side of the screen). Access is also aided by orienting the probe so that the handle does not impede manipulation of the needle and wire. This is especially true of the “hockey stick” probe, which has a handle that can be angled away from the working anatomy.

Fluoroscopy is an important tool for CVL placement in the operating room. It can identify key landmarks before attempting access (e.g., the carina in the case of IJ or subclavian vein access). It also guides wire advancement and dilator/peel-away sheath placement and ensures appropriate catheter position at the end of the procedure. Fluoroscopy also provides the option of contrast injection if needed during access.

The ideal location for the ultrasound machine is across the table from the operating surgeon. Generally, the patient is placed supine on a fluoroscopy-compatible table for vascular access procedures in the operating room. The Trendelenburg position is ideal for jugular and subclavian access to distend target veins and prevent air embolism. When considering small children with short necks and a large occiput, a shoulder roll can be useful to extend the neck and improve ease of access to the IJ vein. Turning the head to the contralateral side is also helpful. It should be noted that with large shoulder rolls and aggressive neck or chest extensions, distances from anatomic landmarks to the SVC/RA junction can be quite distorted compared with normal posture in the postoperative environment. Femoral vein exposure is aided by abduction and external rotation of the leg, and in small neonates, a bump under the hips. Standard skin preparation is used, consisting of chlorhexidine solution in most cases. Hats, masks, and sterile gloves and gowns are worn. If fluoroscopy is to be used, radiation safety protection measures should be observed and ALARA principles followed. Ultrasound probes require a sterile probe cover. Nonsterile ultrasound gel within the cover should be placed directly on the transducer and available sterile ultrasound gel directly on the patient. Of note, avoiding air bubbles in the gel layer between the probe and the probe cover is extremely important since air will cause shadowing, resulting in large areas of nonvisualization in the ultrasound field of view.

Historically, central venous access was obtained by incision and dissection to expose the target vessel. In this technique, a venotomy is performed with or without distal ligation of the vein, and the CVL is placed through the venotomy. If the distal vein will not be ligated, a lateral venotomy with a purse-string suture of 7-0 Prolene is used to secure the catheter. The common anatomic targets of cutdowns are the external jugular vein, facial vein, internal jugular vein just above the clavicle, and the proximal greater saphenous vein. The greater saphenous vein still has some utility in critically ill infants requiring emergent access; however, cutdown techniques have been largely replaced by percutaneous access and IO placement in emergent settings. Despite this, it remains an important and indispensable technique under certain circumstances.

Accessing the vascular lumen via needle venipuncture is the first step in the Seldinger technique. As mentioned, a 21- or 22-gauge micropuncture needle should be used in children. With the landmark technique (without ultrasound guidance), a syringe is used with gentle suction applied so that successful luminal access is confirmed by the return of blood. When using ultrasound, we recommend not using a syringe. We find that this hinders the fine touch of the needle, and the suction applied by the syringe can cause vascular collapse and vasospasm within the small vasculature. With the landmark technique, once blood is seen coming into the syringe, the syringe is taken off carefully without needle movement, and a wire is advanced through the needle and into the lumen of the vessel. The wire should not be forced and should slide effortlessly into the vessel. Ultrasound, if used, can provide a visualization of needle tip entry into the vessel. Once the needle tip is seen in the lumen of the vessel and the vessel wall is no longer tented (the needle has pierced through the wall and not just pushed the wall over), the wire is advanced through the needle and into the vessel. For peripheral access, once the needle is noted to be in the lumen of the vessel, the needle is advanced some distance further (approximately 1 cm) down the barrel of the vessel lumen under ultrasound guidance. This ensures that the needle has not tented the vessel wall, the needle-catheter interface has not dragged the vessel wall into the lumen, and the intraluminal location of the needle or catheter tip has been achieved. This strategy has been shown to reduce extravasation risk during peripheral intravenous access.

With the needle well into the vessel lumen, the wire is advanced, and as noted earlier, the wire should pass smoothly without resistance. If resistance is met, ultrasound or fluoroscopy should be employed to confirm proper wire placement and guide advancement.

Once the wire is in place, maintaining control of its position is critical. Dilators are often passed over the wire to expand the tract to the necessary size. Preferably, serial dilation should be performed under fluoroscopy. Once the tract is appropriately dilated, the catheter is advanced over the wire. The proper position is confirmed with ultrasound or fluoroscopy, and the catheter is secured at the skin. A small angle on the cut of the catheter and a spinning motion as the catheter is passed through the skin can help successfully guide the catheter to traverse the subcutaneous tissue and enter the vein smoothly.

A modification to Seldinger’s technique can be applied with silastic catheters, which are sometimes difficult to place directly over a wire. In this situation, a combination peel-away introducer sheath and dilator is placed over the wire into the vein lumen. The wire and dilator are removed simultaneously, leaving the introducer in place. A finger is quickly placed over the opening of the introducer to prevent backbleeding or an air embolus. The silastic catheter can then be advanced through the introducer into the lumen of the vessel. The introducer can then be split and peeled away, leaving the catheter in place.

Before the widespread use of ultrasound, anatomic landmarks were the most common way to obtain central venous access. Ultrasound has improved the accuracy, ease, and safety of central access, but knowing the anatomy is still important to perform these procedures safely and successfully. The key anatomic landmarks for the common sites of access are as follows:

• Internal jugular vein : The right IJ vein provides a more direct route to the heart than the left. In general, lines function better on the right than the left. If performing the procedure solely with landmarks the needle is inserted into the skin at just below the confluence of the sternal and clavicular heads of the sternocleidomastoid and directed inferiorly towards the ipsilateral nipple at a 30 degree angle to the skin.

• Subclavian vein : Puncture is made just below the clavicle approximately two-thirds of the distance from the manubrium to the lateral clavicular head. At a 30 degree angle from the skin, the surgeon directs the needle medially and slightly cranially just above the sternal notch. If the clavicle is struck, the surgeon should push down on the needle to approach from a lower plane and take a shallower approach to avoid lung injury. Ultrasound can help to easily access the supraclavicular subclavian vein. When ultrasound is placed parallel and rests on the superior edge of the clavicle, the confluence with the IJ and the brachiocephalic can be seen by tilting the transducer. The infraclavicular subclavian can also be accessed with ultrasound, but the vessel is deeper and must be accessed laterally near the deltopectoral groove.

• Femoral vein : Once the femoral artery is palpated just below the inguinal ligament about one-third of the way from the pubic tubercle to the anterior superior iliac spine (ASIS), the femoral vein sits just medial of that position. The skin is punctured well below the inguinal ligament with the needle directed toward the umbilicus at a 30 degree angle to the skin. It is important to be aware of a variation in the neonate, where the femoral vein lies posterior to the artery rather than medially. This is especially true near the inguinal ligament ( Fig. 7.3A and B ). Using ultrasound, the needle can be carefully walked down just past the artery; then, with gentle lateral traction, the side of the needle can push the artery over, and the tip of the needle will be directly over the vein. The needle can then be advanced into the vein ( Fig. 7.3C ). Note that this technique takes a reasonable amount of ultrasound skill.

  

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