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52 Vascular Access in Children
Percutaneous insertion into internal jugular vein For long-term central venous access, either the transcutaneous
The internal jugular vein (IJV) is the most frequently chosen site for (Seldinger) route described above or the open approach can be
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insertion of central venous catheters. The right IJV is commonly used used. The open approach allows the use of smaller veins that can be
because most practitioners are right handed, and the right vein is wider sacrificed, such as the external jugular vein in the neck, the cephalic
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than the left and has a more direct route to the superior vena cava and vein in the deltopectoral fossa, the great saphenous vein, or the
the right atrium. The right lung is also lower than the left so that injury epigastric vein in the groin. The open approach requires an “entrance”
to the lung is less, and the thoracic duct is on the left side. The risk of site where the catheter is inserted into the vein, and an “exit” site where
pneumothorax is less with IJV cannulation. If there is carotid artery the catheter exits the chest wall, with a tunnel between the two. If the
injury, manual compression can easily control the haemorrhage. open approach is used for large veins (internal jugular or femoral), a
For the cannulation, a sandbag is placed behind the patient’s purse-string suture should be put in the anterior wall of the vein and the
shoulders, and the head is turned to the contralateral side. The patient catheter inserted in the centre.
is placed in the Trendelenburg position, and the field cleaned with Complications of Central Venous Access
antiseptic solution. The carotid artery is palpated and gently pushed Catheter clotting and other complications cost the health care system
away at the level of insertion. The vein is approached at 30° to the in the United States about one billion dollars annually. Prevention of
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sagittal plane at the medial border of the sternomastoid midway complications such as those described in the following subsections is
between the thyroid cartilage and the hyoid bone in the direction of the best way to “manage” CVCs.
the ipsilateral nipple. If the syringe is aspirated during insertion, the
vein should be entered within 2–4-cm depth. The Seldinger technique Haemorrhage/haematoma
is then followed. Easier cannulation is now advisable with ultrasonic Brisk bleeding may occur with CVA, especially if the adjacent artery
guidance by using a handheld Doppler probe. 19–21 This not only reduces is injured. Pressure for a few minutes should control the bleeding.
the number of needle passes to locate the vein, but also decreases the Pressure may be difficult to apply if the subclavian artery is injured.
risk of injury to the carotid artery. 21,22 Catheter-related sepsis
Percutaneous insertion into subclavian vein In general, CVA has great advantages but requires special facilities,
The subclavian vein (SCV) may be preferred for central venous access carries significant risks of complications, and is associated with con-
if, for example, the patient has a cervical spine injury, or if the line is siderable financial costs. The insertion of a foreign body with direct
for long-term use (e.g., dialysis, feeding) and this site may be more access to the circulation can be considered a cordial invitation to
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comfortable for the patient. The risk of long-term complications is microorganisms to invade the patient. Oncologic patients receiving
lowest with SCV cannulations. cytotoxics that depress the bone marrow are particularly at risk of sep-
The SCV is the continuation of the axillary vein and originates at the sis. Line infection is therefore the most frequent complication leading
lateral border of the first rib. The SCV passes over the first rib anterior to early removal of the system. Infection may occur either at the time
to the subclavian artery, to join with the internal jugular vein at the of insertion or later during changes of connections. Catheter-related
medial end of the clavicle. The external jugular vein joins the SCV at infection rates vary from 3% to 60%. 24,25 The infection can be at the
the midpoint of the clavicle. exit site, in the tunnel, or catheter-related. Exit-site infections are usu-
The patient is placed supine in the Trendelenburg position. The head ally due to Staphyloccoccus epidermidis, and can usually be managed
is turned to the contralateral side (if C-spine injury has been excluded). by local wound care. Tunnel or pocket infection relates to suppuration
The Seldinger technique is adopted. in the subcutaneous tunnel relating to the foreign body. The port will
The needle is introduced 1 cm below the junction of the middle and need to be removed with antibiotic treatment. Catheter-related sepsis
medial thirds of the clavicle. The needle is directed medially, slightly (especially in patients receiving parenteral nutrition) is the most serious
cephalad, and posteriorly behind the clavicle towards the suprasternal of the catheter-related sepsis.
notch. The needle is slowly advanced while gently withdrawing the Depending on the clinical condition of the patient, a trial treatment
plunger. When a free flow of blood appears, the Seldinger approach with broad spectrum antibiotics (e.g., amoxicillin, metronidazole, and
is followed, as detailed previously. The catheter tip should lie in the gentamicin) should be started in all children with fever and a CVC in
superior vena cava above the pericardial reflection. A chest x-ray situ. Fifty percent or more of the CVC can be salvaged with this policy.
is done to confirm position and exclude pneumothorax. A major If the clinical condition does not improve after 24 hours, removal of
disadvantage of this route is that if there is injury to the subclavian the CVC should be considered. A layer of glycoprotein (the glycocalix)
artery, direct pressure cannot be easily applied to control bleeding. forms on the silastic wall of the catheter, which harbours bacteria that
are protected from antibiotics. The use of ethanol both as prophylactic
Percutaneous insertion into femoral vein and therapeutic modalities in patients with repeated CVC infections has
The femoral route is useful in emergency situations or the patient is been proposed.
coagulopathic, but incidences of infection and thrombosis are the If the catheter is removed due to sepsis, either the tip of the catheter
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highest in this technique. can be rolled on to a plate for culture 26,27 or the lumen of the catheter
The long saphenous vein joins the popliteal vein to form the femoral can be flushed with a nutrient broth (the Cleri technique), which is
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vein, which accompanies the femoral artery in the femoral triangle. To then cultured. The blood through the catheter can also be sampled and
access the vein, the artery is first felt by palpation. Then, keeping a cultured before removal. Kite and others have proposed using a
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finger on the artery, a needle attached to a 10-ml syringe is introduced at small brush to sample endoluminal organisms without removal of the
45 degrees, 1.5 cm medial to the femoral artery pulsation, 2 cm below catheter. Due to the risk of bacterial embolisation, this method has not
the inguinal ligament, until blood is aspirated. The Seldinger technique gained routine use, especially in the intensive-care setting. The risk of
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is then continued as described above.
infection can be reduced by strict adherence to a protocol and reduction
Insertion of catheter for long-term use of the number of caretakers that manipulate the line.
The main difference between long-term and short-term catheters is the Thrombosis
application of tunnelled catheters in the former situation, which allows long- The second commonest complication is thrombosis with or without
term (months or even years) use. The central venous access can either be an obstruction of the catheter. It is thought that thrombosis starts at the site
external silastic catheter (Broviac or Hickman) or an internal device, where of the venepuncture and then migrates along the catheter to eventually
the catheter is connected to a subcutaneous reservoir or port (Port-a-Cath). 23