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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
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