Chapter 34. Nutritional Access Devices

Nasogastric tubes (NG tubes) and nasojejunal tubes (NJ tubes) can be placed at the bedside or under fluoroscopy. These tubes are used as an initial or temporary feeding tube. Generally, the smallest size enteral tube should be chosen, and the tube should be replaced only when necessary. If long-term feedings are anticipated, tubes should be polyurethane or silicone to reduce the frequency of tube replacement and minimize trauma. Use of weighted tubes should be avoided to decrease the risk of bowel perforation.

Gastrostomy tubes (G tubes), transgastric-jejunal tubes (GJ tube), and jejunal tubes are feeding tubes placed using endoscopic techniques, surgery, or interventional radiology. These types of tubes are used when long-term feeding is necessary. The commonly used enteral feeding devices are summarized in eTable 34.1.

Gastrostomy tubes are commonly used in patients who require prolonged enteral nutritional support. Some patients can tolerate prolonged use of nasogastric feedings and avoid a gastrostomy; however, patients who will require tube feedings for more than 2 to 3 months should be considered for gastrostomy tube placement to avoid complications and trauma with the replacement of nasogastric tubes.1 This is particularly important with infants and young children, who may develop a severe feeding aversion exacerbated by nasogastric tube irritation of the nasal passages and oropharynx. Placement of a gastrostomy tube will facilitate progression of oromotor development in some of these children even though they still depend on tube feedings for their nutrition.

Gastrostomy tubes are frequently placed by percutaneous endoscopic gastrostomy (PEG), a fairly simple procedure typically performed under general anesthesia in children. The principal contraindications to placement of a PEG tube are overlying organs (eg, liver, colon), ascites, a coagulopathy, and failure to transilluminate the stomach, often resulting from a major portion of the stomach lying above the costal margin. PEG tubes have been successfully placed in patients who have undergone prior abdominal surgical procedures, including those with indwelling ventriculoperitoneal shunts, and in patients with various deformities, including intestinal malrotation or severe scoliosis. Complications of PEG tube placement include infection (which is decreased by prophylactic antibiotics before placement), pneumoperitoneum, transient fever, pain, bleeding, gastric ulceration from direct erosion of the gastric mucosa by the internal portion of the gastrostomy tube, ileus, gastric separation, gastric fistula, gastrocolic fistula, and tube extrusion. Removal of PEG devices for replacement with a standard gastrostomy tube usually is not performed for 2 to 3 months after placement to allow complete healing and maturation of the gastrostomy. Several tubes are available for use in a gastrostomy, ranging from skin-level, low-profile “buttons” to standard gastrostomy tubes (similar to Foley catheters). The choice of tube depends on the patient’s and caretaker’s preferences and tolerance of the tube by the patient. The skin-level, low-profile buttons are generally preferred in ambulatory, active children.

Awareness of the tube types, equipment, and resources (eg, nursing, nutritional, pharmaceutical, and home care companies) available in the local area is increasingly important for the pediatric practitioner because of the increased administration of outpatient nutritional support. Increased numbers of children with chronic disorders and efforts to decrease length of hospital stay have increased the use of nutritional support devices in the outpatient setting. In most settings, an ostomy nurse, pediatric surgeon or pediatric gastroenterologist manages the routine care of the variety of feeding tubes, as well as any complications that arise.

Care and management of enteral feeding tubes is summarized in Table 34-1.2 A detailed guide to troubleshooting and managing complications of enteral feeding is provided in eTable 34.2. These include local infections (Fig. 34-1), expansion of the size of the ostomy opening with leakage around the tube (Fig. 34-2), development of granulation tissue around the ostomy (Fig. 34-3), inadvertent removal of the tube, movement of the tube (eg, causing pyloric obstruction), and aspiration of gastric contents.

Peripheral intravenous access is usually insufficient to provide adequate nutrition to patients because the nutrient concentrations must be limited to prevent thrombophlebitis. Central venous line (CVL) access is essential for those patients requiring long-term and short-term intravenous nutrition. A CVL is a line whose catheter tip lies in the subclavian vein, superior/inferior vena cava, or right atrium. The type of CVL is determined by the medical diagnosis and length of therapy. Insertion sites may include jugular, subclavian, femoral, antecubital, and umbilical veins. These lines may be tunneled or nontunneled and may have 1 or more lumens. Line placement can be done in the operating room, radiology suite, or at the bedside.

Tunneled CVLs (Broviac-Hickman, Cook, Groshong) are placed through a subcutaneous tunnel away from the vein insertion site. These lines have a Dacron cuff to provide stability to line and function as an antimicrobial barrier. Both placement and removal of tunneled CVLs are usually performed by a surgeon or radiologist. Children requiring prolonged total parenteral nutrition require a tunneled CVL.

Nontunneled CVLs are generally placed directly into a jugular, subclavian, or femoral vein. These lines are typically placed in the hospital setting at the bedside for use while the patient is in the hospital. Since they do not have a Dacron cuff, they are sutured into place and can also be removed at the bedside.

Peripherally inserted central catheters (PICC lines) are chosen for short-term intravenous therapies lasting weeks or months. Generally, they are placed in an arm or a leg and threaded to a central vein or right atrium. These lines can be placed at the bedside or in interventional radiology.

Implanted ports (Port-A-Cath, Med-I-Port) are tunneled lines implanted beneath the skin that contain a single or double reservoir pocketed between the subcutaneous layers and sutured in place. Placement is done in the operating room or radiology suite. Access to the reservoir is obtained with a noncoring needle. These ports are ideal for patients needing repeated but intermittent therapies such as chemotherapy. They need special care only when accessed.

The care and management of CVLs requires that staff and families be educated and comply with vigilant care protocols.3 These involve sterile technique in handling the catheter, minimizing opening or disconnection of the catheter tubing (associated with a higher rate of infection), and dressing changes (every 2–3 days unless otherwise indicated). Exercise, including swimming, is allowable once the catheter track matures, but the dressing should be removed following the activity, the skin cleansed and dried, and a new dressing applied. To avoid complications associated with the infusion, appropriate preparation and infusion of the nutrient solution is critical. This also requires the caretaker (and patient) to be aware of any problems with the pumps or other equipment involved.

Should a catheter be torn or broken, repair kits are available for each of the long-term right atrial Silastic catheters to allow splicing a new extension onto the catheter protruding from the skin.4 However, if the catheter breaks beneath the surface of the skin, it must be removed and a new catheter placed, often in a new site. Other CVL problems and their management are shown in Table 34-2.

Fever or other signs or symptoms of infection always must be treated seriously. In patients with right atrial (central) catheters, fever demands immediate evaluation, and hospitalization is indicated to observe and treat a patient for presumed sepsis if no obvious source for the fever is found. Full physical examinations are performed, and laboratory screening, including complete blood counts and blood cultures (both through the line and by peripheral vein), are obtained. In most cases, and in all infants and young children, antibiotics are started until the culture results are available. Depending on the clinical setting, antibiotics may be discontinued and the patient observed for further evidence of infection if cultures are negative after 72 hours. Repeat blood cultures often are drawn through the catheter 48 to 72 hours after the antibiotics are stopped.

Monitoring is performed both in the home and during frequent clinic visits throughout the treatment period. It is important, particularly when treating patients with central lines in place, to train families to notify the physician or a member of the nutrition support team whenever unusual or abnormal symptoms or signs occur. This will help to decrease potential morbidity and mortality associated with these therapies.