Chapter 16

Nutrition-Related Access Procedures

Because most critically ill patients in intensive care units (ICUs) are unable to maintain their nutritional needs with oral intake or take their medications orally, ICU clinicians use several means to deliver nutrition and medications to such patients. When necessary, enteral access allows both the short- and long-term delivery of nutrients and medications into the gastrointestinal (GI) tract. This chapter reviews the current procedures related to successfully placing nutrition-related access into the stomach or proximal small bowel. It describes the appropriate access choice given certain patient clinical scenarios, operator competence, access to advanced technology, cost considerations, and safety.

Background

According to several multicenter clinical trials, enteral rather than parenteral nutrition is the preferred means of nutrient delivery for patients with intact and functional GI tracts. Enteral nutrition is associated with better clinical outcomes compared to parenteral (intravenous [IV]) nutrition, including a decreased risk of sepsis. Further, since the inception of total parenteral nutrition (TPN) in the late 1960s, no situation remained in which a patient could not be fed. In addition to its high daily cost (relative to enteral feedings), TPN was complicated by serious infectious and metabolic side effects that undermined the beneficial effects of nutrient repletion in many patients. Consequently, creative ways of restoring upper gut function were designed, based on semi-elemental diets and novel feeding tube systems.

The utilization of specific protocols and acceptance of increased gastric residual volumes has allowed most ICU patients to be fed safely and early by nasogastric tube. However, nasogastric feeding is unsuitable for patients at a high risk for aspiration (e.g., those with severely compromised gastric emptying as a consequence of partial obstruction or ileus). These patients require postpyloric tube placement with simultaneous gastric decompression, often via double-lumen nasogastric decompression and jejunal feeding tubes (i.e., so-called “G-J tubes”).

In general, for patients whose enteral access is anticipated for more than four weeks, a more secure and long-lasting type of GI access, such as a gastrostomy or jejunostomy tube, should replace temporary GI access by naso- or oral GI tube or small bore nasoenteral tube. These long-term tubes may be placed by a variety of methods: percutaneously, endoscopically, or by open or laparoscopic surgery. Long-term solutions that have the potential for easy removal include procedures that use percutaneous endoscopic gastrostomy (PEG) tubes, PEG with jejunal extension (PEG-J), and direct percutaneous endoscopic jejunostomy (DPEJ). Together, these advances in enteral access have improved patients’ outcomes and led to a 70% to 90% reduction in the demand for TPN.

Indications

Primarily, long-term enteral feeding tubes are indicated for patients who are intubated for respiratory failure or who have impaired swallowing caused by neurologic conditions (either organic or medication induced); head or facial trauma; luminal obstruction from malignancy or other strictures; motility issues such as gastroparesis; and hypercatabolic states such as cystic fibrosis, extensive burn injury, and Crohn’s disease. Enteral tubes can also be used for hydration and medication administration. Furthermore, PEG tubes may be chosen for gastric decompression in the setting of severe gastroparesis or non operable intestinal obstruction.

Jejunal feeding tubes are primarily used to provide postpyloric nutrition with the aim of decreasing the risk of aspiration of gastric contents or when obstruction or motility issues precludes gastric feeding.

Contraindications

Absolute Contraindications

For nasal or oral access devices, the following are considered absolute contraindications: an actual or suspected basilar skull fracture, nasopharyngeal or esophageal obstruction or recent esophageal surgery or resection, maxillofacial trauma, uncontrollable coagulopathy, large esophageal varices, tracheal-esophageal fistula, nasal stenosis, or nasal mass.

Absolute contraindications for surgical access placement include the following: mechanical obstruction of the GI tract (unless the procedure is indicated for decompression), active peritonitis, uncorrectable coagulopathy, or bowel ischemia.

Relative Contraindications

Relative contraindications to enteral access include GI bleeding, hemodynamic instability, ascites, respiratory compromise, morbid obesity, and certain anatomic alterations. GI bleeding from peptic ulcer disease with a visible vessel or from esophageal varices is associated with a high rate of recurrent bleeding and therefore the decision to attain access and initiate enteral nutrition is recommended to be delayed for 72 hours. Patients bleeding from angiodysplasia, gastritis, or stress gastropathy are at less risk for recurrent bleeding and therefore do not require a delay in seeking access or initiating feeds.

Preprocedure Assessment

Anticoagulant and Antiplatelet Therapy

The American Society for Gastrointestinal Endoscopy (ASGE) and the Society of Interventional Radiology (SIR) issued recommendations regarding the management of anticoagulation or antiplatelet therapy for patients undergoing enteral access procedures (see Table 16.1). The ASGE defines a low-risk procedure as one that includes routine use of endoscopy or fluoroscopy without any percutaneous incision or puncture made. A high-risk procedure includes any enteral access technique that involves an incision or establishment of a fresh stoma (i.e., all new PEG tube insertions). Risk also relates to the probability of a thromboembolic event occurring should the anticoagulation or antiplatelet therapy be stopped before the procedure.

TABLE 16.1

Summary of Recommendations of the Society of Interventional Radiology (SIR) and the American Society for Gastrointestinal Endoscopy (ASGE)

FFP, fresh frozen plasma; INR, International Normalized Ratio; LMWH, low molecular weight heparin.

Low-risk procedure: does not involve an incision; moderate-risk or high-risk procedure: incision or creation of a fresh stoma (see text and sources for details).

^∗SIR regards initial gastrostomy placement as a moderate-risk procedure

^{^}Consider postponing elective procedure in patients with high thromboembolic risk

Modified from Nikolic B, et al: Consensus guidelines for periprocedural management of coagulation status and hemostasis risk in percutaneous image-guided interventions. J Vasc Interv Radiol 23:727–736, 2012 and American Society for Gastrointestinal Endoscopy Standards of Practice Committee. Management of antithrombotic agents for endoscopic procedures. Gastrointestinal Endoscopy 70:1060-1070, 2009.

Antibiotic Prophylaxis

Patients undergoing gastrostomy placement are often at increased risk for infection secondary to poor nutritional status, advanced age, comorbidities, and immune compromise. The incidence of peristomal infection following percutaneous transoral tube placement ranges from 5.4% to 30%. A first-generation cephalosporin or some other similar agent that covers typical cutaneous organisms is recommended. Specific antibiotic prophylaxis is not indicated for these techniques in patients already receiving antibiotics for other reasons.

Technical Considerations

Nasoenteric feeding tubes (NETs) are made of silicone or polyurethane. They are commonly 12 or 14 Fr in diameter and 15 to 170 cm in length (Table 16.2). NETs may be placed unassisted at the bedside or with endoscopic or fluoroscopic guidance. They are designed with various features that assist in successful placement, including removable stylets or guide wires, weighted tips, radiopaque markers, magnets, and suture loops. Double-lumen NETs, through which both the stomach and small intestine can be accessed, are also available.

TABLE 16.2

Summary of Nutrition-Related Access Devices and Procedures