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50 Vascular Access in Children

Care should be taken not to injure the corresponding artery, especially Table 9.2: Advantages and disadvantages of different routes for central
during cutdowns. Once the vein is exposed, the artery should be clearly venous access.
palpated before any vessel is ligated. Complications from intraosseous
infusions are rare, but skin necrosis, compartment syndromes, and Access Advantages Disadvantages
osteomyelitis can occur. Arm veins Simple to access, veins Failure to achieve central
Central Venous Access visible, and palpable position
Not close to vital organs High incidence of
This section discusses the purposes of central venous access (CVA), the
Comfortable for patient thrombosis
techniques and devices tailored to the purposes, and the complications
Low maximum infusion
(both short- and long-term). For long-term central venous access, an rates
operating theatre and general anaesthesia with fluoroscopy are ideal,
Internal jugular Simple to insert Uncomfortable for patient
and will give the best results. The cost-benefit aspect of CVA in the
Direct route to central veins High rate of long-term
African setting is addressed in the final paragraph. complications
High flow-rate
Incidence/Prevalence in the African Setting Low risk of thrombosis Tunneling to chest wall
Percutaneously placed short-term central venous catheters (CVCs) Low risk of pneumothorax more difficult
have been the primary means of central venous access in critically ill
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children. Central venous access for administration of drugs or blood Subclavian/axillary Less patient discomfort Curved incision route
products can be required urgently in patients with severe trauma or Lower risk of long-term Difficult to access
complications
other life-threatening conditions. A chronic need for CVA will arise in Higher rate of pneumo/
patients with oncological or intestinal conditions and for total parental haemothorax
nutrition. About 5 million CVCs are inserted in the United States annu- Femoral High flow rate Higher rate of infection/
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thrombosis
2
ally. The role of the paediatric surgeon in CVA is to offer service to Good for dialysis
paediatric doctor colleagues, and the need for CVA will depend on the Easy insertion More discomfort for patient
type of paediatric (surgical) practice. Difficult in obese patients
The main patient categories are oncology, congenital intestinal
malformations, and short bowel syndrome, with lesser demands from
haematology (sick cell disease) and orthopedics (intravenous antibiotics
for septic arthritis and osteomyelitis). Devices and facilities for CVA are
expensive, so the applicability also depends on financial considerations.
Applications and Indications
The indications of central venous access include:
• rapid infusion of intravenous fluids and blood products;
• frequent blood sampling/blood transfusions;
• administration of substances that are likely to damage peripheral
veins, such as cytotoxics or hyperosmolar parenteral nutrition (PN);
• long-term administration of drugs (antibiotics) or blood products,
obviating the need for repeated venepunctures in children;
• central venous pressure and haemodynamic monitoring of acutely
ill patients; and
• haemodialysis.
Clinical Considerations
Need for emergency central venous access
In patients with life-threatening conditions, the need for CVA is obvious Courtesy: Bard Access Systems.
Figure 9.4: A double-lumen Hickman catheter.
at presentation. Although large-bore peripheral cannulas may be used
for initial access in the emergency room, CVA will be required as soon
as the patient is admitted to the intensive care unit (ICU). Four routes Types of Catheters
are available for transcutaneous insertion of a central venous catheter: A typical catheter for long-term use (such as seen in Figure 9.4) has the
1. cephalic or basilic veins in the arm; following essential features:
• Is manufactured from soft silicon rubber or polyvinyl chloride
2. internal jugular vein;
(PVC).
3. subclavia vein; or
• Is chemically inert, nonthrombogenic, flexible, and radio-opaque.
4. femoral vein.
The advantages and disadvantages of these routes are summarised • May have single-, dual-, or triple-lumen, which allows simultane-
in Table 9.2. ous infusion or infusion of incompatible solutions.
Long-term Use of Central Venous Access • Has a Dacron cuff (e.g., SureCuff ), which has a matrix that
®
Long-term CVA is mainly required for administration of cytotoxics expands after insertion and into which subcutaneous fibrous tissue
and/or parenteral nutrition. The techniques of insertion and the devices grows for good anchorage.
are different from those used in emergency CVA.
®
• Is a VitaCuff , which incorporates an antimicrobial collagen sponge
designed to prevent infection.