Pediatric Gastrostomy and Gastrojejunostomy



Pediatric Gastrostomy and Gastrojejunostomy


Bairbre Connolly



Introduction


Nutrition is vitally important for children’s growth and development. Ensuring adequate nutrition in the at-risk child (because of disease or disability) is a challenge. If oral feeding is not possible, adequate, or safe, alternative methods are required. Nasogastric (NG) or nasojejunal (NJ) tubes are suitable for temporary feeding requirements (<3 months). Longer-term requirements can be achieved through tubes placed surgically (open, laparoscopic), endoscopically (percutaneous endoscopic gastrostomy [PEG]) or radiologically (antegrade, retrograde).1-5 There are a wide variety of tube types, each with inherent advantages, disadvantages, complications, and required maintenance procedures.1,2,3,6,7 This chapter describes an approach to enterostomy access in children, focusing on those aspects most pertinent to the pediatric age group and emphasizing how they differ from adults.



Indications


Children referred for gastrostomy (G) or gastrojejunostomy (GJ) frequently require lifelong feeding support. Growth, development, and maturation are important factors to take into consideration when deciding to place a G/GJ tube in a child.8,9 The underlying diagnoses most commonly encountered include (1) neurologic impairment such as congenital, developmental, or acquired brain abnormalities (e.g., cerebral palsy), (2) gastrointestinal problems (e.g., severe gastroesophageal reflux, absorptive problems), (3) generalized problems (e.g., genetic/chromosomal abnormalities or “syndromes”), and (4) organ-specific conditions (e.g., severe complex cardiac diseases, end-stage renal failure, cystic fibrosis, high metabolic states, catabolic states such as oncologic diseases with severe mucositis/esophagitis, etc.).8,1014 Achieving specific weight or growth milestones is a prerequisite to undergoing certain surgeries or transplant; enteral nutrition is a means to promote this growth. Within any of these diagnostic categories, individual patients may have more than one clinical indication for their G/GJ, such as failure to thrive, recurrent aspiration, inadequate caloric intake, gastroesophageal reflux disease, swallowing dysfunction, special dietary requirements, or medications (e.g., human immunodeficiency virus [HIV]-infected patients receiving highly active antiretroviral therapy [HAART]).15,16


A child with any of the above indications/diagnoses and associated severe gastroesophageal reflux disease is unlikely to tolerate G feeds. A surgical antireflux procedure combined with gastrostomy is one approach.17,18 In the medically fragile child with significant comorbidities, a GJ tube may be a more suitable option. Referral preferences depend on institutional practices, local expertise, and the like. There is a major difference for families between maintaining a child on G feeds (bolus feeds, shorter feeding hours) compared to GJ feeds (more continuous feeds, longer hours), so it is often worthwhile to try G feeds initially, despite reflux. Removal of the NG tube alone may alleviate reflux and facilitate tolerance of G feeds. If, however, gastroesophageal reflux remains problematic, the radiologic G tube can be readily converted to a GJ tube.19,20 A GJ tube does not provide protection against aspiration of oropharyngeal secretions from above or gastric secretions from below. GJ tubes are also indicated in children with duodenal or gastric outlet issues (e.g., superior mesenteric artery syndrome, duodenal trauma, etc.).



Contraindications


There are few absolute contraindications to placing a G or GJ tube. They include uncorrectable severe coagulopathy, unfavorable abnormal anatomy where there is no safe percutaneous route to the stomach (such as may occur in severe scoliosis) post congenital diaphragmatic hernia repair or anterior abdominal wall defect surgery (e.g., omphalocele).21 Intestinal obstruction is a contraindication unless placed for decompression (e.g., severe motility disorders).


Relative contraindications include coagulopathy requiring correction, clinical instability, or critical comorbidities. Ascites may require interim drainage until the G-tube tract is healed. Neonates with esophageal atresia without a tracheoesophageal fistula (i.e., a gasless abdomen) can undergo a radiologic G tube, but it requires sonographically guided needle puncture of the stomach to inflate the stomach with air, since an NG tube cannot be passed from above.22 Dilated gas-filled colon anterior to the stomach can be deflated by aspirating the luminal gas using a 27G needle, T-piece and Luer-Lok syringe.5,23 Placing a G tube in the presence of a ventriculoperitoneal (VP) shunt may be associated with a risk of ascending ventriculitis.2426 Temporally distancing the G tube insertion as much as possible from the VP shunt insertion (>1 month), and physically separating it from the shunt tubing in the abdominal wall and the peritoneum may help to reduce this chance of infection.2427



Assessment


In children, there are significant psychosocial factors that have to be addressed a priori because they have major impact on parents/caregivers in their relationship with the child and acceptance of a feeding tube.9,28,29 The importance of these factors should not be underestimated, and parental expectations must be realistic and informed.7,28,30 Assessment requires a comprehensive multidisciplinary approach to ensure that a G/GJ tube is medically indicated and that the parents support the decision, are in agreement to proceed, and are thoroughly educated regarding what caring for a child with a G tube entails (i.e., site care and tube maintenance).7,28,30 This involves discussions among the patient’s family, referring physician, an expert in gastrostomies (specialist pediatrician or nurse practitioner), a dietitian, an occupational therapist, and interventional radiology (IR).



Technique


General Aspects of Pediatric Interventional Radiology Procedures


There are important differences between interventional procedures in children and adults.31 Dosages of drugs and intravenous (IV) fluids must be calculated tightly on a per kilogram basis. Temperature preservation and monitoring is crucial in the small child who is prone to hypothermia; body warmers such as Bair Huggers (Arizant Healthcare Inc., Eden Prairie, Minn.), plastic coverings, chemical blankets, and hats are required.31,32 The IR suite must be equipped with different sizes of pediatric devices (e.g., BP cuffs, endotracheal tubes, pediatric resuscitation cart, etc.). Sedation should be performed either by anesthesiologists or persons trained in pediatric sedation and airway rescue (Pediatric Advanced Life Support [PALS] certification). Radiation protection is especially important in children. Dose-reduction strategies include low pulse rate fluoroscopy (e.g., 4 or 7 pulses/s), limited use of magnification and alternate use of postprocessing zoom, removal of the grid (vendor specific in children < 20 kg), last image hold techniques, and so forth.3335 Protection of the operator is also important, given patients’ small size, the operator’s proximity to the beam, and potential hand exposure.36



Preprocedure


The process of obtaining informed consent from parents/substitute decision maker is time consuming. Ideally it is obtained after family education and prior to the day of the procedure, rather on entry to the IR suites. Procedural risks include bleeding, injury to bowel or abdominal viscera, and inability to reach the stomach (≈1%). Postprocedural risks include infection/peritonitis (≈2%-3%), tube dislodgement, retention anchor suture (RAS) problems, any specific problems secondary to their comorbidities or underlying diagnosis, and common site and maintenance issues.7,37,38 Procedural mortality is rare.


For fasting, a commonly used rule of thumb in children is the “2-4-6-8 rule” (2 hours for clear fluids, 4 hours for breast milk, 6 hours for formula, and 8 hours for solids). Avoidance of prolonged fasting and hydration with IV or oral (PO) clear fluids containing dextrose is important to avoid hypoglycemia. Adult guidelines suggest checking full blood cell count and coagulation prior to gastrostomy, but this is not routine in pediatric practices.39



Procedure Techniques


The technique described here is the percutaneous retrograde method we currently practice. A preprocedural time out (±the aid of checklist) is conducted, including need for and dose of antibiotics, glucagon, and dextrose-containing IV fluids; date of last menstrual period (where applicable); radiation protection strategies; any additional procedures to be performed; and any patient-specific precautions (e.g., metabolic issues, allergies, medications, skin issues, etc.).40,41


Most frequently, G and GJ tubes are placed under IV sedation or anesthesia, although placement is possible using local anesthetic only. The inferior margin of the liver, spleen, and left costal margin are identified with ultrasound and marked on the skin with a safe skin marker. The lateral edge of the rectus muscle and the position of the superior epigastric artery may also be outlined. Dilute barium may be infused rectally to outline the transverse colon. The abdomen is then prepped and draped in the usual fashion. Prophylactic antibiotics are given (30 mg/kg IV cephazolin). Glucagon IV (0.2-0.5 mg) may be given to achieve gastric atony and pyloric constriction.42,43 An NG tube is inserted and secured.



Gastrostomy


A combination of ultrasound and fluoroscopy is used. Air is introduced into the stomach through the NG tube. Once tense, a site is chosen, ideally lateral to the rectus muscle and 2 cm or more from the lower costal margin to allow for growth. Alternatively, the puncture can be in the midline or perhaps (least favored by the author) through the rectus muscle and sheath. Local anesthetic (Xylocaine 1%, 0.5 mL/kg; or bupivacaine 0.25%, 1 mL/kg) is infiltrated down to the peritoneum. A small skin incision is made. The stomach is punctured using an 18G needle preloaded with a single pediatric RAS (Cook Medical, Bloomington, Ind.), using a short, sharp, fairly vertical stab, and confirmed with contrast. The RAS is deployed into the stomach with a 0.035-inch straight short guidewire. It is our practice currently to use only one RAS; others may choose to use any number from none to four. The needle is removed over the wire, and slight tension is maintained on the end of the thread with a small forceps for gastropexy. The tract is dilated over the wire using the appropriate-sized dilator and holding additional tension on the RAS thread. The dilator is then exchanged for a pigtail catheter. The position is confirmed with contrast injection (±additional air in stomach via NG) in posteroanterior, lateral, and various oblique projections to document that it is intragastric (gastric rugae outlined with contrast, rotation of the pigtail freely in the gastric lumen, movement of the NG) and clear of other bowel loops (steep craniocaudal x-ray projection showing tube separate from colon). The thread of the RAS is wound around a small roll of gauze until it is gently taut and secured. The NG tube and G tube are secured and put to gravity drainage. Colonic barium is drained via the rectal tube, which is then removed.



Gastrojejunostomy


When placing a GJ tube, some interventionalists may omit the use of barium and glucagon. However, both can be used without interfering with the safe and successful insertion of a GJ tube. The initial steps are as outlined for gastrostomy. The RAS is deployed with a long 0.035-inch floppy-tipped wire (e.g., Bentson [Cook Medical]) and the needle removed. Using a directional catheter (e.g., 5F JB1 [Cook Medical]) advanced directly over the wire, it is directed to the pylorus and negotiated through the duodenum and into the upper jejunum. The catheter is then removed, the tract dilated to the required size, and the GJ then placed over the wire. The retention mechanism is secured, the GJ position confirmed with contrast, the NG put to straight drainage, and the GJ tube is capped off.



Antegrade Gastrostomy Tube Placement


This “push-pull” method is favored by some centers; insertion is more complicated but has the advantage of greater tube security and less risk of dislodgement.44,45 Access to the stomach is obtained through the mouth with a wire and snare. The esophagus must be patent. The stomach is punctured from outside, aiming for the open snare in the stomach. The wire is snared and exteriorized through the mouth. The G tube is pulled down through the esophagus using a loop mechanism that draws the tube and its bumper into the stomach and out the abdominal wall antegradely. The external bumper is then advanced snug to the abdominal wall. The tube is trimmed to length.4446


Dec 23, 2015 | Posted by in INTERVENTIONAL RADIOLOGY | Comments Off on Pediatric Gastrostomy and Gastrojejunostomy
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