vascular access overview
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Safe with most
medications
Silicone central venous
catheter (eg, Hickman,
Broviac)
Long termLess
thrombogenic
Decreased
infection rate
Safe with most
medications
Increased cost
Requires surgical insertion
Implantable vascular-access
device (ports)
Long or permanentLow visibility,
improved body
image
Lowest rate of
infection
Increased cost
Requires surgical insertion
Intraosseous Emergency accessRapidly and
easily inserted
Lowcomplication
rate
Safe with
resuscitation
medications
Not for long-term use
Potential for osteomyelitis
Venous cutdown Emergency access;
possibly long term Direct exposure
to vein
Increased rate of
dislodgement and infection
Requires incision
The decision to obtain vascular access can be a major challenge to the physician. Factors, such as the patient's
age and size, the availability of venous access sites, and even the anticipated length of use complicate the
decision. The length of anticipated use, which ranges from short-term or temporary to long-term and even
permanent, must be considered when the decision is made to obtain access because this may affect the choice
of catheter. For example, though peripheral vascular catheters can be used for a variety of indications, such as the
administration of IV fluids and numerous medications, they cannot be used for chemotherapy or total parenteral
nutrition (TPN). Finally, though obtaining vascular access is generally a safe procedure, it is not without
complications, some of which can be life threatening.[3]
For patient education resources, see the Circulatory Problems Center, as well as Venous Access Devices.
Indications
Indications for obtaining vascular access in children are numerous. In general, vascular access can essentially be
divided into 2 broad categories: peripheral and central venous. Peripheral, short-term catheters are safe for giving
many IV medications (eg, antibiotics), for providing maintenance IV fluids, and for blood sampling for laboratory
tests. However, numerous fluids and medications (eg, hyperosmolar solutions, resuscitative drugs) cannot be
given through peripheral catheters because of local and venous irritation. Children who require long-term treatment
(eg, antibiotics), emergency medications (eg, inotropes, medications to manage cardiopulmonary arrest),
chemotherapy, and TPN require central venous access.[4]
General indications for central access include administration or facilitation of the following:
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Total parenteral nutrition
Chemotherapy
Venous access in chronically ill children who require repeated venous punctures for blood sampling and
medication
Long-term antibiotics (eg, longer than 34 wk)
Emergency access (eg, to manage cardiopulmonary arrest or trauma)
Critical-care monitoring (eg, of pulmonary wedge pressure) and medications (eg, inotropes)
Types of Catheters
Peripheral Catheters Percutaneous peripheral catheters
Peripheral venous catheters are the most commonly used catheters in most hospital settings. They are relatively
safe and easy to insert. Improvements in technology have produced catheters with small calibers, resistance to
bacterial colonization, and lowered rates of thrombotic complications. They can be used for a variety of indications
and are safe with a variety of commonly administered medications.
The dorsal veins of the hands are excellent choices for catheterization, and they should be the first choices when
placing peripheral catheters. The dorsal veins of the foot are excellent first choices in neonates and infants, but
should be avoided in older children (eg, toddlers) if possible because catheters placed here are painful and difficult
to maintain without becoming easily dislodged. Superficial scalp veins (frontal, superficial temporal, posterior
auricular, and occipital veins) are also convenient access points in neonates, but shaving of the surrounding hair isrequired, and the catheters can be difficult to maintain. Care must also be taken when scalp veins are used to
avoid inadvertent cannulation of the temporal artery or 1 of its branches. Although other veins, such as the median
antecubital, basilic and median cephalic veins are relatively large and easy to cannulate, these sites should be
reserved as second choices in case a PICC or venous cutdown is required.
The greater saphenous vein is another excellent choice in the pediatric population because of its large size and
consistent anatomy. These veins can often be cannulated with ease without direct visualization or palpation. With
a sound knowledge of the anatomy, the femoral vein is another potential site for vascular access. However,
because of concerns with infection and thrombotic complications, this site is generally used only in emergency
situations. Extreme care must be taken when femoral lines are inserted to avoid damage to the femoral nerve or
artery. These lines are best used for short-term access because of their proximity to the groin. Once inserted,
care should be taken to keep the insertion site as clean as possible to minimize the risk of line infection. Finally,the external jugular vein may be used to gain vascular access (see the image below).
Percutaneous external jugular vein access. Note that the head is in the dependent position to allow for f illing of the vein.
External jugular veins can be difficult to cannulate because the infant must often be restrained and placed in a
dependent position to allow the veins to be visualized. In addition, catheters are difficult to stabilize here and
frequently become dislodged; these disadvantages preclude their routine use.
When placing peripheral catheters, the physician may use tourniquets, transillumination, or heat lamps to facilitate
their insertion. Infants and small children may also benefit from the application of local anesthetic agents (eg,
lidocaine and prilocaine [EMLA] cream) to the insertion site to minimize pain and discomfort during catheter
placement. When using topical anesthetic creams, one must plan in advance to allow at least 1 hour for the cream
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to provide the desired effect. Care should also be taken in selecting an anesthetic agent, as some may cause
vasoconstriction of the vessel, making insertion more difficult.
When placing a peripheral catheter, the physician should always anticipate the need for adequate restraint.
Parents and nursing staff can help minimize movement of the child during catheter placement. After the peripheral
catheter is placed, adequate stabilization should be used to prevent its dislodgement. Tape and an arm board
might be applied to the extremity. A "flashback" of blood into the catheter tubing may not occur in infants, leading
the physician to assume that the catheter is improperly placed. In such a case, the catheter should be flushed
with sterile normal sodium chloride solution. Infiltration of surrounding tissues with this solution indicates improper
placement.
Peripheral venous cutdown catheters
Peripheral access can be gained by using a surgical venous cutdown. In the past, this method was frequently
used in children in whom access was difficult or in emergency situations. However, this technique has fallen out of
favor because of its related morbidity, relatively short patency, and technical difficulty. This technique still has a
limited role in emergency situations when other peripheral and intraosseous attempts fail. The cutdown approach
poses virtually no risk of pneumothorax or hemothorax and allows for direct visualization of the vein. The exposed
veins are often of small caliber, which limit the size of the catheter that can be used. In addition, the distal end of
the vein is typically ligated; therefore, the vein is precluded from use as future vascular access.
The saphenous vein is usually the primary choice for surgical venous access, but the antecubital and femoral
vessels can also be use. The course of the saphenous vein anterior to the medial malleolus of the tibia makes it apopular choice for cutdown access (see the image below).
Saphenous vein cutdow n. Note the relationship of the saphenous vein to the medial malleolus. A linear incision is made perpendicular to
the vein.
To perform a saphenous cutdown procedure, a sterile field is prepared with the lower extremity immobilized and
the foot turned laterally. After 1% lidocaine is subcutaneously injected over the vein, an incision is made
perpendicular to the vein. Careful blunt dissection of the subcutaneous tissue with a hemostat is used to isolate
the vein. Silk sutures are then looped around the vein: 1 proximal and 1 distal. The distal loop may be used to
ligate the vein. Gentle tension is then applied to the proximal vessel loop, and a venotomy is made with a number
11 blade in a parallel fashion to avoid transition of the vessel (see the image below).
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Saphenous vein venotomy. A venotomy is made during saphenous vein cutdow n w ith a number 11 blade (or iris scissors). Care must be
taken to avoid complete transection of the vein. The venotomy should be made parallel w ith the vein to avoid this complication.
The cannula is then inserted into the vein and secured in place by tying the proximal loop. Care must be taken to
avoid occluding the cannula (see the image below). The wound is closed with sutures and dressed. In infants and
newborns, the saphenous vein can be accessed at the level of the femoral junction in the proximal thigh.
Insertion of the saphenous vein catheter. After the vein is located and venotomy performed, the catheter is inserted into the vein. Use of
the proximal suture loop can facilitate catheter placement.
Although peripheral catheters are commonly used, they are all limited to short-term usage, small-to-moderate
infusion volumes, and solutions of a low osmolarity. The most common complication of peripheral catheters is their
dislodgement or occlusion, which leads to extravasation of fluids into the extravascular tissues. If this occurs, the
catheter should be removed. Extravasation of infusates, especially those of a hypertonic or irritative nature, can
have dire consequences, such as tissue necrosis and compartment syndrome.
Intraosseous Catheters
Intraosseous catheters were commonly used in the past. Their use has declined with advances in IV catheters and
alternative access techniques. However, the intraosseous catheter still has a major role in life-threatening
emergency situations when other access methods fail and when time is of the utmost importance. Pediatric
resuscitation guidelines from the American College of Surgeons Advanced Trauma Life Support (ATLS) manual
recommend the use of intraosseous access when "venous access is impossible due to circulatory collapse or for
whom percutaneous peripheral venous cannulation has failed on two attempts" in children aged 6 years or
younger. In addition, ATLS guidelines recommend that intraosseous access should be established in the newborn
if umbilical venous access cannot be rapidly achieved.[5, 6]
Intraosseous vascular access is based on the anatomic presence of noncollapsible veins in the medullary sinuses
in the bone marrow (see the image below). This venous network drains directly into the central venous circulation
by means of emissary veins, resulting in rapid and almost immediate absorption. A variety of drugs (including
resuscitation drugs), crystalloid solutions, and even blood products may be given rapidly by means of the
intraosseous route. The large bore of these catheters enable the administration of blood without lysing RBCs.
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Venous drainage of the bone marrow . The venous netw ork of the bone marrow is used for intraosseous puncture to obtain vascularaccess.
Achievement of intraosseous vascular access is simple, rapid, and consistent when known anatomic landmarks
are used (see the image below).[6] In infants and small children, the proximal tibia is the primary choice for
insertion. In older children and adolescents, the sternum can be accessed. Other sites for insertion include the
distal tibia, distal femur, distal radius, and os calcis. As with all catheters, intraosseous catheters should not be
placed in an already injured limb. For placement in the proximal tibia, the anatomic landmarks must first be
recognized. With a large-bore (16- or 18-gauge) bone-aspiration needle, the insertion is made 1-3 cm below and
just medial to the tibial tuberosity by advancing through bone into the marrow space. Correct placement is
confirmed with the aspiration of marrow and with the easy infusion of fluid.
Low er-extremity anatomy for intraosseous vascular access. The intraosseous needle is placed approximately 1-3 cm below the tibial
tuberosity.
Complications are rare with intraosseous vascular access, but they have been reported. The most commonreported complication is osteomyelitis, but this is rare (< 1%). Other complications include fracture, compartment
syndrome, leakage at the insertion site, and failure of infusion due to bending of the needle or occlusion of the
needle with bone marrow. Intraosseous catheters are not recommended for long-term use and should be removed
within 1224 hours after their insertion.
Peripherally Inserted Central Catheters (PICC)
Peripherally inserted central catheters, or commonly referred to as PICC lines, have become increasingly popular
in patients who require intermediate- to long-term venous access. They have become the most popular vascular
access in patients in the neonatal intensive care unit (NICU).
PICC lines share attributes of both peripheral and central venous access and are readily inserted at the bedsideunder strictly sterile conditions (as for all centrally placed vascular catheters). PICC lines are composed of
biocompatible materials and come in a variety of sizes. Large PICCs can have multiple lumina.
Careful attention must be paid to choosing a suitable vein. The saphenous vein or the veins of the antecubital fossa
(basilic, brachial, cephalic vein) are those most commonly used in clinical practice. After a suitable vein is located
(by using ultrasonographic guidance if necessary), [7] the PICC line is inserted into the peripheral vein by using a
peel-away introducer needle. When the vein is successfully cannulated, the catheter is the advanced to a desired
length into a large central vein. Correct positioning of the PICC line is then confirmed with a chest radiograph.
PICC lines are suitable for a number of indications, including TPN, blood sampling, and administration of nearly all
medications. They can be used in both the hospital and home setting, a feature that makes them a popular choice
for outpatient therapy. PICC lines offer many advantages in the pediatric population, including lowered overall cost
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and risks compared with surgical vascular-access methods. In addition, they have a solid record of efficacy.
Although no evidence suggests that PICC lines decrease the risks of infection or thrombotic complications, they
virtually eliminate the problems of pneumothorax, air embolization, and cardiac arrhythmias. PICC lines are less
likely than traditional peripheral vascular-access methods to become dislodged, and they can be easily removed
when treatment is stopped or when complications, such as infection or phlebitis, occur.
Because of their often-small lumen, one disadvantage of using PICC lines is an increased occlusion rate. Another
concern is overusage that potentially exhausts upper-extremity venous-access sites. This may have serious
implications in chronically ill patients, especially those with renal failure who may eventually require arteriovenous
fistulas for dialysis access.
Central Venous Catheters
Central venous catheters (CVCs) offer many advantages over peripheral lines. They offer a reliable method of
infusing large volumes of fluid; they can be maintained long term; and they allow for the administration of blood
products, TPN, antibiotics, and chemotherapy drugs. In addition, they are frequently used for critical-care
monitoring (eg, monitoring of central venous pressure).[8]
Percutaneous Polyethylene Catheters
A variety of veins are suitable for polyethylene catheters, including the subclavian, internal jugular, and femoral
veins. Like PICC lines, polyethylene catheters can be readily placed on an elective basis or in an emergencysituation. They can usually be placed with only local anesthetic, depending on the child's age and
cooperativeness, by using the Seldinger technique. A variety of CVCs are available with either single or multiple
lumens.
After a suitable vein is located, a sterile field is prepared. For the Seldinger technique, the patient is posit ioned
appropriately in the Trendelenburg position to access the subclavian and internal jugular veins or in a flat to reverse
Trendelenburg position to access the femoral veins. Local anesthetic (1% lidocaine) is injected locally. Young
children may require light, monitored sedation. The syringe and needle are then passed subcutaneously in the
direction of the vessel with constant negative pressure applied to the syringe; this point cannot be stressed
strongly enough.
When venous blood returns to the syringe, needle advancement is stopped. Should no blood return, the needle is
completely withdrawn, and another attempt is made. Attempts to adjust the needle in the tissue pose a risk of
damaging the surrounding tissues, including the vein, artery, and nerve. When blood is aspirated, the syringe is
removed, and the guidewire is advanced through the needle into the vein. The guidewire should pass easily. If
resistance is met, do not attempt to advance the wire further. In this case, the wire should be carefully withdrawn;
the syringe should be reattached to the needle, and a further attempt is made to aspirate blood. If no blood is
aspirated, the needle is withdrawn, and a further attempt is undertaken. If blood is aspirated, the needle can be
carefully rotated 90, and a second attempt at passing the wire is made.
Difficulty in passing the guidewire should alert the physician to obtain additional help, including radiographic
guidance if necessary. Care must also be taken to maintain control of the guidewire at all times. If the guidewire
meets no resistance, it is inserted a few centimeters into the vein. Pay careful attention to the ECG monitor, if
available, to detect and avoid cardiac arrhythmias. After the guidewire is in place, the needle is carefully removed
to avoid dislodging the wire. A small incision is made in the skin at the insertion site. This incision should be nobigger than the width of the catheter to be inserted.
Many CVC kits contain dilators, which can be used with extreme caution. Again, these should pass without
resistance. The catheter is then threaded over the wire and into the vessel. This is a critical point where strict
control of the wire must be maintained to avoid losing it in the vein. After the catheter is in place, each lumen
should be aspirated to prevent an air embolism. Blood should be easily withdrawn from all lumina. The lumina are
then flushed with heparinized sodium chloride solution; the catheter is secured to the skin with more than 1
suture. The insertion site is covered with a sterile dressing.
The subclavian vein is the preferred route for central venous access (see the image below). However, careful
attention must be paid when CVCs are inserted in this position, and the physician must have thorough knowledge
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of the central venous anatomy to minimize potential complications. The subclavian vein site is well tolerated by
children, it is easy to dress and monitor, and it has good patency.
Percutaneous subclavian vascular access. Anatomic landmarks should be clearly identified before vascular access is attempted. The
needle is guided tow ard the sternal notch.
The subclavian vein is accessed by means of the infraclavicular approach at a point inferior and lateral to the
midclavicular bend. The needle is inserted toward the suprasternal notch by guiding the needle posteriorly at an
angle of approximately 30 to the chest wall. In children younger than 1 year, the subclavian vein arches
superiorly. This variation must be taken into account when vascular access is obtained in this population. When
the internal jugular veins are assessed, the right jugular is preferred because of its straight descent into the right
atrium and because of the decreased risk of injury to the thoracic duct, which is near the left internal jugular vein.
Likewise, thorough understanding of the anatomy is required to minimize complications when the jugular vein is
accessed (see the image below). Care must be taken to avoid injury and cannulation of the carotid vessels when
this approach is chosen. Numerous complications can occur when a CVC is placed. These are discussed in
Complications below.[9]
Percutaneous internal jugular venous access. The anatomic landmarks and the carotid artery must be c learly identif ied before venous
access is attempted. The carotid artery lies medial to the vein. The needle is inserted at the apex of the triangle formed by the 2 heads of
the s ternocleidomastoid muscle.
Silicone CVCs
Like polyethylene central catheters, silicone catheters (eg, Broviac or Hickman catheters) are percutaneously
placed into a central vein, but they are tunneled a distance from the insertion site. For this reason, they are the
preferred percutaneous catheter for long-term treatment needs, such as TPN or chemotherapy. Silicone catheters
are more pliable and less traumatic to veins than polyethylene catheters. In addition, they have an attached cuffnear the proximal end, which is often impregnated with antibiotics. Taken together, the tunneled feature and cuff
improve stability of the catheter and decrease the risk of infection. Evidence suggests a lowered rate of thrombotic
complications with silicone catheters because of their increased pliability, but this assertion has not been
conclusively demonstrated in clinical trials. Various silicone catheters are available with both single and double
lumina.
Because of the tunneled feature, silicone catheters require surgical insertion. The subclavian, internal jugular, and
femoral veins can be used.[10] In neonates, the external jugular and saphenous veins can also be selected. The
catheter is advanced under fluoroscopic guidance to ensure correct placement. The extravascular portion of the
catheter is then tunneled under the skin to an exit site, which is usually on the anterior chest wall. Once inserted,
they are sutured in place, flushed with heparinized sodium chloride solution, and covered with an appropriate
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dressing.
Implantable Vascular-Access Devices
Implantable vascular-access devices, or ports, have become the device of choice for patients who require long-term
or even permanent access. Ports eliminate many of the problems associated with CVCs, such as infection,
restriction of daily activities, altered body image, and the need for frequent dressing changes. Central venous lines
with implantable subcutaneous ports (or reservoirs) are an excellent and often preferred means of vascular access
in pediatric patients with cancer. These catheters have excellent durability, as they can often be accessed more
than 100 times, and the overlying skin acts as a protective barrier for infection. These types of catheters improvethe cosmetic appearance, they allow for regular activities, and they do not require frequent dressing changes or
special handling.
A number of devices are commercially available (eg, Port-A-Cath, Mediport) with either single- or double-lumen
injection ports. The device consists of an injection port made from a durable, hard protective shell (eg, titanium)
with an overlying silicone diaphragm, which is surgically implanted in the subcutaneous tissue (commonly the
anterior chest wall). The injection port is connected to a silicone catheter, which is placed into the vein by using
the Seldinger technique or direct cutdown. Like silicone venous catheters, ports are tunneled a distance from the
vascular-access point. Because of the size of the port, children must usually weigh >10 kg to be good candidates
for port placement.
To access the port, a Huber needle (a special side-holed needle) is used to puncture the diaphragm. The needle
does not damage the diaphragm and allows the device to be used repeatedly for long-term access. After the
surgical site heals, the port requires no local care or dressings. The major advantage of ports is a substantially
lowered rate of infection compared with other access devices. One disadvantage to ports is that they require
surgical insertion and removal when treatment ceases or complications arise.
Other Vascular-Access Sites
Umbilical Vascular Access
The umbilical vein can be used as an access site in neonates during the first few days of life. After the first few
days of life, surgical cutdown may be required to access the umbilical vein. Like other venous-access sites,
umbilical venous access can be used for blood sampling, fluid and drug administration, and even monitoring ofcentral venous pressure (see Table 2). Two umbilical arteries are present in the umbilical stump, and these may
be used to monitor arterial blood pressure, sample blood, and administer fluids and drugs.
Table 2. Indications for Catheterization of the Umbilical Vein or Umbilical Artery (Open Table in a new window)
Use of the Umbilical Vein Use of the Umbilical Artery*
IV access in low-birth weight infants
Emergency IV access for resuscitation, medications, and
fluids
Blood sampling
Monitoring of central venous pressureExchange transfusion in the newborn
Continuous blood-pressure
monitoring
Exchange transfusion in the
newborn
Arterial blood gas samplingInfusion of resuscitation drugs
Infusion of maintenance solutions
* Umbilical-artery catheterization should not be used when peritonitis, necrotizing enterocolitis, omphalocele, or
gastroschisis is present.
The umbilical cord usually contains 3 vessels: 1 umbilical vein and 2 arteries. The umbilical vein is usually the
largest of the 3 vessels with a thin wall, and it is located the 12-o'clock posit ion. To access the umbilical venous,
the child must be supine and restrained. A sterile field is then created around the umbilicus. A silk suture is
looped around the base of the umbilical stump (see the image below).
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Umbilical vein catheterization. A, Umbilical tape or silk suture is looped around the base of the umbilicus, and the distal umbilical stump is
removed. B, The umbilical vein is located (usually in the 12-o'c lock position), and the lumen is exposed. C, The catheter is advanced into
the lumen. D, After a satisfactory position is achieved, the catheter is secured in place.
The distal stump is then incised off, and the vessels are quickly occluded to prevent excess blood loss. After the
vessel is located, a cannula is passed directly into the vessel, and the tip is advanced to a point above the celiac
axis for umbilical-artery lines. For venous access, the catheter tip should go into the umbilical vein and into the
inferior vena cava. The catheter tip should be at the level of the inferior vena cava next to the diaphragm. A plain
abdominal radiograph is used to confirm placement.
Miscellaneous venous sites
On rare occasions, the veins commonly used for vascular access are not available. In these instances, other
venous-access points must be sought. Veins that can be used for such circumstances include the azygous,
hemiazygous, intercostal, and hepatic veins; the inferior vena cava; and other unusual collateral vessels. Use of
the azygous and hemiazygous veins requires formal thoracotomy, which limits their potential. Intercostal veins can
usually be accessed without formal thoracotomy. The inferior epigastric and lumbar veins can be accessed with a
surgical cutdown procedure. Before access to these sites is attempted, the physician should consult an
interventional radiologist. Radiologic intervention may assist in locating the most suitable veins for access.
Arterial Vascular Access
Arterial cannulation is required to assess blood gases and to continuously monitor blood pressure, especially in
critically ill patients. A number of sites are available, including the radial, axillary, femoral, posterior tibial, and
dorsalis pedis arteries. Because of poor collateral flow, the brachial artery should not be used. Likewise, the
temporal artery should not be used because of the risk of thrombotic complications. The radial artery is most
frequently used because of ease of access at this point.
Before the radial artery (or any other artery) is cannulated, an Allen test is performed to assess for adequate
collateral flow, and the results should be clearly documented in the patient's chart. An Allen test for the radial
artery is performed by occluding both the radial and ulnar arteries at the wrist. One of the arteries (not the one
chosen for cannulation) is then released, and the patient's hand is checked for return of blood flow; the hand
should remain perfused. A successful result on the Allen test demonstrates collateral flow between the arteries.
After the artery is located, the field is sanitized, and the index and middle fingers of the operator's nondominant
hand are placed on the artery to asses the pulse wave (see the image below).
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Arterial cannulation of the radial artery. Tw o fingers are placed at the wrist to locate and help visualize the course of the artery. The
artery is then cannulated after collateral flow is assessed (Allen test).
In this way, the operator can mentally visualize the course of the artery. The needle is then inserted into the artery.
After the needle is withdrawn, pressure must be applied to promote hemostasis and to prevent hematoma
formation. Simply placing a bandage at the site without direct pressure is unacceptable.
Complications
Overview
Complications for vascular access can be divided into acute (during the insertion period or shortly after) or long
term (see Table 3). The physician should have a thorough knowledge of the anatomy and of the potential
complications from the procedure to identify and quickly treat any complications that may arise. In addition, the
physician should have working knowledge of the vascular-access device to be used to avoid confusion and
potential mishandling of the catheter. Finally, a thorough preoperative evaluation should be undertaken. It should
include a review of the results of coagulation studies and attention to the placement of previous vascular-access
devices. Informed consent should be obtained and documented on the patient's chart.
Table 3. Complications of Inserting Catheters for Vascular Access (Open Table in a new window)
Acute Long Term
Pneumothorax
Vascular damage (eg, perforation, dissection)
Air embolism
Aberrant catheter placement
Damage to the thoracic duct
Cardiac complications (eg, cardiac irritation, cardiac
perforation)
Local tissue trauma or damage (eg, bleeding into
surrounding tissues, nerve injury)
Infection and sepsis
Thrombotic complications (eg, DVT,
pulmonary embolus)
Phlebitis of the cannulated vessel
Superior vena cava syndrome
Catheter dislodgement and migration
Note. DVT = deep vein thrombosis.
Acute Complications
Pneumothorax is the most common acute complication with central venous access, with reported rates of up to
4%. For this reason, an upright chest radiograph (or lateral decubitus image if the patient cannot sit upright)
should be obtained after central venous access is attempted. The physician should personally view the image after
the procedure and obtain radiologic interpretation if necessary.
Small (< 10%), uncomplicated pneumothoraces usually do not require immediate evacuation unless evidence of
compromised ventilation is present. Small pneumothoraces require monitoring to ensure that they resolve
satisfactorily. Small pneumothoraces usually resolve spontaneously at a rate of approximately 1% per day. Failure
for a small pneumothorax to resolve, enlarging pneumothorax, or ventilatory compromise is an indication for
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evacuation (eg, with a thoracostomy tube). Of note, central venous lines that surgeons placed in the operatingroom rarely result in pneumothorax or bleeding complications.
Other complications are listed in Table 3, but this list is by no mean exhaustive. Apart from the strategies
described above, other measures to reduce complications include proper patient positioning, adequate assistance
(eg, for restraint), holding positive pressure ventilation during needle insertion, and radiologic (eg, fluoroscopic)
guidance.
Long-Term Complications
The risk of long-term complications from vascular access increases with the duration of catheterization. The most
common long-term complications include infection, thrombosis, catheter occlusion, and, in some cases, catheter
migration (see Table 3). Migration may cause the catheter to malfunction. In some cases, it can lead to perforation
of the vessel wall.
Infection
Infection is the most common complication of long-term vascular access. The incidence of infection varies
depending on the type of catheter, the location of placement, and the patient population. As a rule, any central
venous line that is used for long-term access is prone to become infected at least once. Despite speculation that
certain types of catheters are associated with high infection rates, the literature does not support these claims
except in the case of implantable vascular-access devices. Numerous clinical factors have also been implicated incatheter-related infections. These include the patient's age. Rates of infection are highest in the neonatal
population and in patients with short-bowel syndrome, neutropenia, or other chronic illnesses.
Catheter infection is suspected in patients with a vascular-access device when they have a fever and when an
identifiable bacterium is isolated from blood samples and the catheter device. Erythema surrounding the catheter
exit site may represent only skin irritation. Therefore, it is important to attempt to determine if the catheter is truly
the source of infection. Attempts may be made to salvage the catheter by empirically administering antibiotics
through the catheter. In critically ill children, the most prudent advice is to remove the catheter and to attempt
vascular access at a point away from the infected area. However, limitations in the venous access sites available
in chronically or critically ill children should be considered before a catheter is removed.
In most children, removing the infected catheter eliminates the source of infection. Empiric antibiotics may not be
warranted unless the child has signs of sepsis. Commencing broad-spectrum antibiotics is generally warranted incritically ill children after appropriate cultures are obtained. The physician should consult local infection control and
antibiotic policies before commencing antibiotics. If antibiotics are started, they should cover coagulase-negative
Staphylococcus bacteria because these are most frequently identified as the organisms responsible for CVC
infection.
Antibiotics should be continued for at least 48 hours or until cultures results are available. After 48 hours, the
patient's clinical condition should be reassessed, and the antibiotics are discontinued if they are no longer needed
to prevent antimicrobial resistance. Tenderness, induration, erythema, and, occasionally, purulent drainage at the
exit site may represent a subcutaneous tunnel or port-pocket infection. This type of infection usually requires
removal of the venous access device and treatment with IV antibiotics as necessary. As a rule, most catheter-
related infections can be successfully treated with IV antibiotics without line removal. However, line removal and
appropriate anti-microbial therapy are often needed to manage infections caused by fungal microorganisms orgram-negative bacteria.
Preventing catheter-related infection should be a high priority for all healthcare workers. Prevention includes strict
hand-washing protocols, aseptic techniques for handling the catheter, and meticulous care of the catheter site.
Infection rates decrease when specific catheter-care protocols are in place and when well-trained nursing staff
handle the catheters.
Thrombosis
Venous thrombosis is another frequent complication of long-term venous access. Several etiologic factors are
implicated in thrombosis of vascular-access devices, including the type, size, and location of the catheter, as well
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as the patient's underlying condition. Large catheters with multiple lumina likely disturb the surrounding blood flow,
leading to thrombosis.
Catheter-associated thrombi may range from small accumulations of fibrinous material in or around the catheter to
large, potentially fatal thrombi. Clinically significant thrombosis can result in total occlusion of the vessel,
thromboembolism (eg, clot in the right atrium or a pulmonary embolism), or superior vena cava syndrome. Patients
with suspected venous obstruction should undergo venography, echocardiography, or spiral CT to locate the
thrombus. In general, children with clinically proven vascular thrombosis should be treated with anticoagulants (eg,
heparin for 7-10 d). Evidence suggests a strong association between thrombosis and infection. Again, all
healthcare workers must exercise extreme vigilance when a vascular-access device is being used.
When catheter patency is reduced because of partial thrombosis, streptokinase, tissue-type plasminogen
activator, urokinase, or heparin have all been used with success. Evidence supports the prophylactic use of
urokinase to flush the catheter; this technique improves catheter patency. Central vascular-access devices should
be flushed regularly (eg, with heparinized sodium chloride solution, urokinase) to help reduce the incidence of
thrombotic occlusion. Chronic vascular thrombosis and occlusion is not unusual in children who have had several
previous central lines. For this reason, vascular ultrasonography and/or angiography may be helpful before central
lines are inserted in these children.
Summary
The requirement for vascular access is common among children in the hospital setting. This requirement mayrange from short-term or temporary needs to long-term or even permanent access. A variety of vascular-access
options are available to the physician who cares for children to meet the required treatment needs.
The indication for and duration of vascular access should be carefully considered before placement is attempted to
help minimize the number of attempts and the trauma to the child and their family. The physician should have a
thorough knowledge of the anatomy, confidence in undertaking the procedure, and awareness of the likely
complications associated with each type of access.
After the catheter is in place, careful handling and strict aseptic technique are required during the care and
maintenance of the line to reduce the risk of infection. Careful vigilance is required to prevent both acute and long-
term catheter-related problems.
Contributor Information and DisclosuresAuthor
Shawn D Larson, MBChB Assistant Professor of Surgery, Division of Pediatric Surgery, Department of
Surgery, University of Florida College of Medicine
Shawn D Larson, MBChB is a member of the following medical societies:American College of Surgeons,
American Pediatric Surgical Association,Association for Academic Surgery, and Society for Surgery of theAlimentary Tract
Disclosure: Nothing to disclose.
Coauthor(s)
Andre Hebra, MD Chief, Division of Pediatric Surgery, Professor of Surgery and Pediatrics, Medical University
of South Carolina College of Medicine; Surgeon-in-Chief, Medical University of South Carolina Children's
Hospital
Andre Hebra, MD is a member of the following medical societies:Alpha Omega Alpha,American Academy of
Pediatrics,American College of Surgeons,American Medical Association,American Pediatric Surgical
'
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, , ,
Group, Society of American Gastrointestinal and Endoscopic Surgeons, Society of Laparoendoscopic
Surgeons, South Carolina Medical Association, Southeastern Surgical Congress, and Southern Medical
Association
Disclosure: Nothing to disclose.
Ramanathan Raju, MD, MBA, CPE, FRCS, FACS Medical Director and Director of Medical Education,
Coney Island Hospital; Clinical Professor of Surgery, New York College of Osteopathic Medicine, Associate
Clinical Professor of Surgery, SUNY Health Sciences Center
Ramanathan Raju, MD, MBA, CPE, FRCS, FACS is a member of the following medical societies:American
Association for the Advancement of Science, American College of Angiology, American College of Critical Care
Medicine,American College of Phlebology,American College of Physician Executives,American Society of
Abdominal Surgeons,American Trauma Society,Association for Academic Surgery,Association for Surgical
Education, International College of Surgeons, International College of Surgeons US Section, New York
Academy of Sciences, New York County Medical Society, Royal College of Surgeons of England, Society of
Critical Care Medicine, and Society of Laparoendoscopic Surgeons
Disclosure: Nothing to disclose.
Steve Lee, MD Physician in Plastic, Reconstructive, and Hand Surgery, Plastic Surgery, PLLC
Steve Lee, MD is a member of the following medical societies: American College of Surgeons andAmerican
Society of Plastic Surgeons
Disclosure: Nothing to disclose.
Specialty Editor Board
Jonah Odim, MD, PhD, MBA Senior Medical Officer, Transplantation Immunology Branch, Division of Allergy,
Immunology, and Transplantation, National Institute of Allergy and Infectious Diseases, National Institutes of
Health
Jonah Odim, MD, PhD, MBA is a member of the following medical societies: American College of Cardiology,
American College of Chest Physicians,American College of Physician Executives,American College of
Surgeons,American Heart Association,American Society for Artificial Internal Organs,American Society of
Transplant Surgeons,Association for Academic Surgery,Association for Surgical Education, Canadian
Cardiovascular Society, International Society for Heart and Lung Transplantation, National Medical Association,
New York Academy of Sciences, Royal College of Physicians and Surgeons of Canada, Society of Critical Care
Medicine, and Society of Thoracic Surgeons
Disclosure: Nothing to disclose.
Mary L Windle, PharmD Adjunct Associate Professor, University of Nebraska Medical Center College of
Pharmacy; Editor-in-Chief, Medscape Drug Reference
Disclosure: Nothing to disclose.
John Myers, MD Director, Pediatric and Congenital Cardiovascular Surgery, Departments of Surgery and
Pediatrics, Professor, Penn State Children's Hospital, Milton S Hershey Medical Center
John Myers, MD is a member of the following medical societies: American Association for Thoracic Surgery,
American College of Cardiology,American College of Surgeons,American Heart Association,American
Medical Association, Congenital Heart Surgeons Society, Pennsylvania Medical Society, and Society of
Thoracic Surgeons
Disclosure: Nothing to disclose.
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, , , , ,
Pediatrics, New York University School of Medicine
Daniel Rauch, MD, FAAP is a member of the following medical societies:Ambulatory Pediatric Association,
American Academy of Pediatrics, and Society of Hospital Medicine
Disclosure: Baxter Honoraria Consulting
Chief Editor
Mary C Mancini, MD, PhD Professor and Chief of Cardiothoracic Surgery, Department of Surgery, LouisianaState University School of Medicine in Shreveport
Mary C Mancini, MD, PhD is a member of the following medical societies: American Association for Thoracic
Surgery,American College of Surgeons,American Surgical Association, Phi Beta Kappa, Society of Thoracic
Surgeons, and Southern Surgical Association
Disclosure: Nothing to disclose.
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