Nasogastric and Feeding Tube Placement

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Chapter 40

Nasogastric and Feeding Tube Placement

Leonard E. Samuels

Nasogastric (NG) intubation is commonly used to evaluate or treat bowel obstruction, ileus, or gastric hemorrhage, preoperatively or postoperatively, or to administer food or medication into the gastrointestinal (GI) tract. Patients with long-term feeding tube complications and those requiring replacement or other manipulation of tubes are frequently seen and treated in the emergency department (ED).

Properties of NG and Feeding Tubes

Polypropylene is the material most commonly used for Levin and Salem sump NG tubes (Fig. 40-1), but it is too rigid for long-term use as a feeding tube. Polypropylene tubes are less likely to kink than others but are more capable of creating a false passage during placement. Latex (rubber) tubes are moderately firm, require greater lubrication for passage, are relatively thick walled, and induce a greater foreign body reaction than do tubes made of other common materials. Latex, especially in latex balloons, deteriorates more rapidly than other material does.¹ Foley catheters are primarily latex, although silicone Foley catheters are available for patients with latex allergies. Silicone tubes are thin walled, pliable, and nonreactive; however, the walls of silicone tubes are weaker and may rupture if fluid is introduced into a kinked tube.² Polyurethane tubes are nonreactive and relatively durable. Rigidity varies from manufacturer to manufacturer, depending on the thickness of the tube. A stylet may aid in the passage of polyurethane and silicone tubes, but it increases rigidity and the potential for tissue dissection, especially with tubes that have a small distal end-bulb.³ Some feeding tubes have weights, which are usually made of tungsten and are nontoxic if released into the GI tract.

Figure 40-1 Salem sump tube. This tube contains a second lumen that allows venting during continuous suction. 1, Pigtail extension (blue) of the air vent lumen; 2, connector for attachment of the suction lumen to the vacuum line; 3, gastric end with suction eyes; 4, insertion depth markers.

NG Tube Placement

Review Box 40-1 Nasogastric tube placement: indications, contraindications, complications, and equipment.

Indications and Contraindications

The simplest NG tube is the Levin tube, which has a single lumen and multiple distal “eyes.” The advantage of the Levin tube is its relatively large internal diameter (ID) in proportion to its external diameter. The theoretical disadvantage is that a Levin tube should not be left hooked up to suction after the initial contents of the stomach have been drained because the suction will cause the stomach to invaginate into the eyes of the tube and thereby blocking future tube function and potentially cause injury to the stomach lining. Levin tubes are therefore rarely used in the ED. The Salem sump tube is preferred over the Levin tube for chronic use as a drainage device because it has a separate (blue-colored) channel that vents the distal main lumen to the atmosphere (Fig. 40-2). This vent helps prevent excessive vacuum from forming at the tip of the tube. Note that both intermittent suction and wall unit vacuum can exceed the venting capacity of the second lumen, so the vacuum setting should be less than 120 mm Hg.

Figure 40-2 Diagram of the Salem sump tube. A, General design. B, Diagram of the double-lumen principle for suction. (A and B, Courtesy of the Argyle Division of Sherwood Medical, St. Louis.)

The major indication for NG tube placement and suction is to aspirate the stomach contents in patients with gastric outlet or intestinal obstruction, gastric or bowel distention, prolonged ileus, or gastric, esophageal, or bowel perforation. Draining the dilated stomach of excessive contents lessens the chance of vomiting and possibly aspiration and provides marked relief of symptoms in patients with intestinal obstruction. The presence or anticipation of depressed mentation potentially justifies NG tube placement to protect the airway, especially if the stomach is full or vomiting is uncontrolled. Bag-valve-mask ventilation often distends the stomach with air, and a postintubation NG tube can improve ventilation, prevent vomiting, and increase patient comfort.

Trauma patients may need an NG tube as part of the evaluation for GI injury or to decompress the stomach before surgery or peritoneal lavage. A radiopaque NG tube may help delineate transdiaphragmatic hernia of the stomach after trauma. A deviated NG tube is a nonspecific sign of traumatic aortic rupture. An NG tube may be used to instill air into the stomach for documentation of a suspected gastric perforation by enhancing visualization of free air under the diaphragm on an upright chest film. In patients unable to swallow, an NG tube may be passed to administer medications or oral contrast material for a computed tomography (CT) scan.

For the evaluation and treatment of upper GI bleeding, indications for NG tubes differ among clinicians, and practices vary widely. Clinical judgement prevails as the best arbitrator, but the true clinical value of an NG tube in patients with GI bleeding is probably less than traditionally promulgated. Although insertion of an NG tube may prompt earlier endoscopy, the procedure has not been demonstrated to improve clinical outcomes.⁴ NG aspiration can help localize bleeding in only a minority of patients with GI hemorrhage. Patients who vomit a significant amount of proven bloody material have had upper GI bleeding; they do not need an NG tube for diagnosis. Such patients are best evaluated by endoscopy, although when a history of bleeding is suspected, stomach aspiration may have a role in diagnosis to confirm the presence of blood. In patients without hematemesis, NG aspiration uncovers less than half the patients with upper GI hemorrhage and thus cannot be used to unequivocally rule out upper GI bleeding. Even a rapidly bleeding duodenal ulcer may not produce blood in the stomach. Some contend that emptying a markedly dilated stomach of blood and stomach contents may reduce the rate of bleeding, but data are lacking. Patients with presumptive upper GI bleeding, which includes those with melena, those younger than 50 years old, and those with a hematocrit lower than 30, need upper endoscopy.^5,6 Patients passing clots or blood per rectum or those with known previous lower GI bleeding are usually experiencing lower GI bleeding.⁶ Except when frankly bloody fluid is obtained, a nasogastric aspirate is diagnostically unhelpful. Small bits of darkish material, bloody mucus, or positive Gastroccult or guaiac tests probably represent sequelae of the procedure, whereas a clear appearance and negative tests still miss most bleeding distal to the stomach. Patients with a bleeding pattern indicative of a Mallory-Weiss tear may need neither an NG tube nor endoscopy.

NG tubes can provide the earliest indication of high-volume esophageal or gastric bleeding. Although variceal rupture may potentially be caused by insertion of instruments into the esophagus, several studies suggest that passage of an NG tube is generally safe, even in patients with esophageal varices. Use of NG tubes for the evaluation and monitoring of upper GI bleeding should be judicious rather than universal.

Increasingly, the literature suggests that most other causes of vomiting are best controlled with medication. Postoperative ileus ends sooner and patients recover faster without an NG tube after various studied abdominal surgeries.⁵ NG tubes prolong the hospital stay, pain, and hyperamylasemia in those with mild to moderate pancreatitis.^7,8 Many patients are better off without an NG tube from the point of view of safety, comfort, and speed of recovery.

In an awake and alert patient with a preserved gag reflex, passage of a NG tube has not been demonstrated to result in significant pulmonary aspiration, even when vomiting occurs during passage. NG tubes are, however, contraindicated in patients with a special predisposition to injury from placement of the tube. Patients with facial fractures who have sustained an injury to the cribriform plate may suffer intracranial penetration with a blindly placed nasal tube.⁹ Severe coagulopathy is a relative contraindication to passage of an NG tube. In patients with a coagulopathy or significant facial or head trauma, an NG tube passed through the mouth may be a better alternative (Fig. 40-3). Patients who have esophageal strictures or a history of alkali ingestion may suffer esophageal perforation. Gagging will decrease venous return and increase cervical and intracranial venous pressure. Comatose patients may vomit during or after NG tube placement. Indwelling NG tubes predispose patients to pulmonary aspiration because of tube-induced hypersalivation, depressed cough reflex, or mechanical or physiologic impairment of the glottis.⁷ Aspiration is also quite common with nasoenteral feedings in debilitated patients, hence the use of a gastrostomy feeding tubes for this condition. An NG tube should be avoided when possible in patients who have undergone gastric bypass surgery or lap banding procedures.

Figure 40-3 A nasogastric (NG) tube may enter the cranium or facial soft tissues in patients with severe head or facial trauma. Those with a coagulopathy may experience significant bleeding from nasal or pharyngeal trauma during passage of an NG tube. In such cases, a standard NG tube inserted through the mouth (as shown above) may be a better alternative.

Extended irrigation of the stomach with water in a patient with upper GI hemorrhage can lower serum potassium levels,¹⁰ and animal studies suggest that cold water lavage can cause rather than control bleeding.^11,12 No study has shown irrigation to be effective in the control of bleeding,^13,14 and vigorous lavage with cold water may lower the body temperature. Erythromycin has been demonstrated to be effective in clearing the stomach for endoscopy,^15,16 and its success is better substantiated than irrigation.

Equipment

Passage of standard NG or feeding tubes can be messy and may be accompanied by coughing, retching, sneezing, bleeding, and spilled water or stomach fluid. For this reason, both the patient and clinician should be gowned; cleanup may be reduced if the bib area is covered with a towel and a supply of tissues or washcloths is available. For standard NG tube placement, a piston or bulb syringe (with a catheter slip-tip) should be available. NG feeding tubes should have a compatible 50- or 60-mL syringe (some are Luer compatible and others are slip-tip compatible).

Tape torn into 4-inch strips or a commercial NG tube holder (e.g., Suction Tube Attachment Device, Hollister, Libertyville, IL) should be handy for securing the tube after placement. Cotton-tipped applicators and tincture of benzoin may be helpful in securing the tube to the nose if the skin is greasy. Make sure that the feeding tube is designed for duodenal passage if this is desired—such tubes are usually longer than regular feeding tubes.

Procedure

Explain the procedure to the patient. Written informed consent is not standard. If the patient is alert, raise the head of the bed so that the patient is upright. Place a towel over the patient’s chest to protect the gown, and place an emesis basin on the patient’s lap.¹⁷ Position the tube (typically a 16- or 18-Fr sump) so that the insertion distance can be estimated, and mark the distance with tape or by noting the markers printed on the proximal end of the tube. A simple method is to measure the tube from the xiphoid to the earlobe and then to the tip of the nose. Then add 15 cm (6 inches) to this number (Fig. 40-4, step 5).¹⁸ It is a common error to fail to estimate the proper length of tube before passage, which can result in the tip of the tube positioned in the esophagus or coiled excessively in the stomach. Check the nares for obstruction. Assess patency by direct visualization, by gentle digital nasal examination, and by having the patient sniff while first one and then the other nostril is occluded. Pass the tube down the more patent naris.

Figure 40-4 Nasogastric tube placement.

Relief of Discomfort

Ameliorate the pain and gagging associated with tube placement by using vasoconstrictors, topical anesthetics, and antiemetics. Because patients rate NG tube placement as very painful, one of the most painful procedures performed in the ED, use these adjuncts whenever time and the clinical situation permit (Fig. 40-5). Spray topical vasoconstrictors, such as phenylephrine (0.5% Neo-Synephrine) or oxymetazoline (0.05% Afrin), into both nares at first in case one side proves to be problematic (see Fig. 40-4, step 2). The nares, nasopharynx, and oropharynx should all be anesthetized at least 5 minutes before the procedure. Gagging is reduced if the pharynx is anesthetized as well as the nose. Combinations of tetracaine, butyl aminobenzoate, and benzocaine (Cetacaine), nebulized or atomized (spray cans or bottles) lidocaine (4% or 10%), and lidocaine gels (2%) are most commonly used. Lidocaine preparations of 10% are most useful. Lidocaine may be nebulized and delivered by face mask with the equipment used to administer bronchodilators to asthmatics (see Fig. 40-4, step 3). This method has been found to be superior to lidocaine spray for reducing gagging and vomiting and increasing the chance of successful passage.^19,20 Cullen and coworkers concluded that nebulized nasal and pharyngeal lidocaine (4 mL of a 10% solution) reduces the discomfort associated with passage of an NG tube better than placebo does and without any lidocaine-related toxicity.²¹

Figure 40-5 Insertion of a nasogastric (NG) tube has been termed one of the most painful and unpleasant procedures performed in the emergency department, and it should not be used unless specifically indicated. Whenever possible, some form of topical anesthesia for both the nose and the pharynx should be used at least 5 minutes before passing an NG tube.

After a topical vasoconstrictor and anesthetic are administered, lubricate the tube with viscous lidocaine or lidocaine jelly.²² Lubrication and anesthesia of the nares can be facilitated by using a syringe (without needle) filled with 5 mL of an anesthetic lubricant, such as 2% lidocaine gel (Fig. 40-4, step 4). Simply putting anesthetic jelly on the tube just before insertion will not provide any anesthesia. Topical anesthetics are generally quite safe, but pay attention to the total dose of anesthetic administered to avoid toxicity.²³ Note that each milliliter of a 10% lidocaine solution contains 100 mg of lidocaine and can be absorbed systemically. In rare cases, topical benzocaine has caused methemoglobinemia even with the relatively small amounts used for endoscopy.²⁴

Although no standard exists and supportive data are sparse, some clinicians administer ondansetron (Zofran, 4 mg) or metoclopramide (Reglan, 10 mg) intravenously 5 minutes before passage of an NG tube to potentially reduce nausea and gagging and, secondarily, to improve the pain and prolongation of the procedure that gagging engenders. Metoclopramide may have additional benefits on the discomfort associated with NG tube insertion, unrelated to its antinausea effects. Ondansetron is preferred for nausea because metoclopramide can cause agitation or facial and tongue spasm, but these effects can be reversed rapidly with the administration of 25 mg diphenhydramine intravenously.

Under direct vision, not blind forcing, insert the tube gently into the naris along the floor of the nose under the inferior turbinate and not upward toward the nasal bridge (Fig. 40-6; also see Fig. 40–4, step 6). If mild resistance is felt in the posterior nasopharynx, apply gentle pressure to overcome this resistance. If significant resistance is encountered, it is better to try the other nostril because bleeding or dissection into retropharyngeal tissue may occur if force is used. Once the tube passes into the oropharynx, pause to help the patient regain composure and enhance the chance for cooperation with the rest of the procedure.

Figure 40-6 Endoscopic view of the nasal cavity before and after the application of oxymetazoline nasal spray. The nasogastric tube (NGT) is passed under the inferior turbinate, which is made more patent after the application of topical vasoconstrictors. The operator should actually look into the nose during insertion to properly guide the tube, not force it blindly. (From Thomsen T, Setnik G, eds. Procedures Consult—Emergency Medicine Module. Copyright 2008, Philadelphia, Elsevier Inc. All rights reserved.)

If the patient is alert and cooperative, a common option is to ask the patient to sip water from a straw and swallow while you advance the tube into and down the esophagus (see Fig. 40-4, step 7). This may facilitate passage of the tube. Once the tube is in the nasopharynx, flex the patient’s neck to direct the tube into the esophagus rather than the trachea. In an intubated, anesthetized, or paralyzed patient, two stacked positive pressure breaths lasting 1 to 2 seconds each via a face mask provide similar relaxation of the upper esophageal sphincter for a brief 4- to 5-second window, and this markedly increases successful tube placement.²⁵

Some gagging during the procedure is common and is not an indication to halt attempts at passage. Withdraw the tube promptly into the oropharynx if the patient has excessive choking, gagging, coughing, or a change in voice or condensation appears on the inner surface of the tube because this indicates the possibility of passage of the tube into the trachea. Inspect the tube by way of the mouth to detect coiling or respiratory passage. If the tube is lateral to the midline, this suggests correct position in the esophagus.²⁶ Once the tube is in the esophagus, advance it rapidly to the previously determined depth. Passing the tube slowly prolongs discomfort and may precipitate more gagging.¹⁷

Confirmation of Tube Placement

Before the NG tube is secured, confirm successful placement by nonradiographic means or by auscultation. Use more than one method when in doubt because all methods of confirmation have some possibility of error. Radiographic evaluation is the most definitive way to confirm the position of an NG tube, but it is not standard to routinely obtain radiographic confirmation.

A quick and simple method of confirmation is to insufflate air into the NG tube and auscultate for a rush of air over the stomach (see Fig. 40-4, step 8). If increased pressure is required to instill the air or if no sounds are heard, the tube may be malpositioned or kinked. Suspect an esophageal location if the patient immediately burps on insufflation.

If alert and cooperating, the patient will feel whether the tube is entering the trachea or lungs and can notify the inserter. Unfortunately, if the patient is comatose, struggling, or demented, the tube may pass into the lungs unrecognized. Insufflation is often insufficient to detect this type of malpositioning.³ The insufflation test is also unreliable in detecting a tube that has advanced past the stomach and into the small bowel.²⁷ In such patients, radiographic verification may be prudent.

Aspiration of stomach contents, especially if pH-tested, is more reliable and can be performed if positioning is in question. If the pH is less than 4, there is an approximately 95% chance that the tube is in the stomach and nonrespiratory placement is almost guaranteed.²⁸ Although aspirated fluid can occasionally be obtained from the lung or pleural space, the pH should be 5.5 or higher.²⁹ Approximately 4% of correctly placed tubes have aspirates with a pH higher than 5.5. Causes include duodenal reflux, antacids, H₂ blockers, or recent instillation of formula or medications.²⁹

If awake and cooperative, ask the patient to talk. If the patient cannot speak, suspect respiratory placement. Note that with small-bore tubes, patients may still be able to speak despite tracheal placement.³⁰

Once correct tube position is tentatively confirmed, secure the tube. If the patient requires abdominal or chest radiographs for other diagnostic purposes, place the NG tube before obtaining the films. An NG tube deviated to the right may occasionally be seen in patients with traumatic rupture of the aorta, but this is not a reliable indicator.

Securing the Tube

The NG tube is generally secured to the patient with tape attached to both the tube and nose (Fig. 40-4, step 10). A butterfly bandage (or tape on each side of the nose) that coils around the NG tube is a typical approach. The nose and tube should both be clean and prepared with tincture of benzoin if possible. If the tape should let go or require repositioning, both the tape and the tincture of benzoin must be replaced. It is wise to also secure the tube to the patient’s gown so that a tug on the tube will encounter this resistance before pulling on the tape securing the tube to the patient’s nose. A rubber band tied around the tube with a slipknot (Fig. 40-7) and pinned to the gown near the patient’s shoulder is effective. It is critical to ensure that the tube is secured in such a way that it does not press on the medial or lateral aspect of the nostril. Necrosis or bleeding can result if a tube is not secured correctly.

Figure 40-7 Attach the nasogastric tube to the patient’s gown with a rubber band and a safety pin so that a tug on the tube pulls the gown and not the tape holding the tube in the patient’s nose.

When a Salem sump is used, the blue pigtail must be kept above the level of the fluid in the patient’s stomach or the stomach contents may leak back through the vent lumen. If a patient needs to ambulate with a sump tube in place, fit the blue pigtail into the plastic connector at the end of the suction lumen. This creates a closed loop that should not leak.

Placement Issues

If the patient is intubated, deflate the balloon of the endotracheal (ET) tube briefly to allow passage of the NG tube. In a nonintubated unconscious patient, the NG tube is easily misplaced into the pulmonary tree. This complication may be missed during the procedure in cases in which the gag and cough reflexes are suppressed and the patient cannot talk. In addition, the absence of swallowing may prevent successful passage of the tube. In comatose or ventilated patients, several techniques have been studied to aid in passage of the NG tube. Using Magill forceps to grip the tube or stenting the end of the tube with a gum bougie passed into the most distal tube eye can help stiffen and control the tube. The combination and sequence of techniques used will depend on the clinician’s expertise, the equipment available, and the level of sedation.

If less traumatic strategies fail, an ET tube can be prepared with an ID that is slightly larger than the external diameter of the NG tube. Slit it along its lesser curvature from the proximal end to a point 3 cm from its distal end. Pass the NG tube through a naris into the oropharynx. Visualize the tip of the tube with a laryngoscope, grasp it with Magill forceps, and pull it out of the mouth. Pass the slit ET tube (generally 8 mm in ID) through the mouth into the esophagus.³¹ Alternatively, pass a 7-mm-ID slit ET tube directly through the nose into the esophagus.³² Passage into the esophagus is facilitated by the stiffness of the larger ET tube and does not require active swallowing. Thread the tip of the NG tube into the ET tube and advance it into the stomach (Fig. 40-8). Remove the slit ET tube from the esophagus. When the distal part of the ET tube is visible, slit the unslit 3-cm distal part with scissors. Remove the ET tube, and the NG tube will remain in place.³³ Advance any slack tubing with forceps or pull it back nasally, depending on the final depth required for the NG tube. The technique can also be performed by passing the slit ET tube nasally, which saves the trouble of orally advancing or nasally retracting any slack in the tubing.^33,33 Make sure that the NG tube can pass into the 7-mm-ID tube and that the ET tube is well lubricated inside and out.

Figure 40-8 Diagrammatic representation of separation of the nasogastric (NG) tube from the guiding endotracheal (ET) tube through the slit in the guiding ET tube. The NG tube has first been passed through the nose and is pulled out through the mouth. The tip of the tube is then threaded into the guiding ET tube to ensure passage down the esophagus. The guiding ET tube is removed from the esophagus before being separated from the NG tube. Note the previous placement of another ET tube in the trachea (partially shown) to avert passage of the guiding ET tube into the trachea. (Modified from Sprague DH, Carter SR. An alternate method for nasogastric tube insertion. Anesthesiology. 1980;53:436.)

In a particularly passive, intubated, sedated, unconscious, or toothless patient, guiding the NG tube with fingers into the pharynx is occasionally successful (Fig. 40-9A).³⁴ Displacing the larynx forward by manually gripping and lifting the thyroid cartilage can aid in inserting the tube,³⁵ as can simple jaw elevation. A soft nasopharyngeal airway, well lubricated, is at times easier to pass nasally than an NG tube, and then the lubricated NG tube can be passed through it. In addition, it affords some protection to the nasal mucosa if multiple attempts at passing the NG tube are necessary or if it is particularly important to minimize bleeding or trauma. Cooling an NG tube increases its rigidity, and coiling it can increase the curvature of the tube, both of which may help pass the tube. Alternatively, the NG tube and larynx can be visualized with a laryngoscope, endoscope, or the GlideScope (Fig. 40-9B).³⁵ Under laryngeal visualization, manipulation and lifting of the jaw and neck flexion can help align the tube for passage under direct vision into the esophagus.

Figure 40-9 A, Passage of a nasogastric (NG) tube through the nose of an intubated patient can be difficult. An endotracheal tube is in the trachea via the mouth. Place the second and third fingers in the posterior pharynx. Depress the tongue with the fingers. Guide the NG tube down the esophagus by passing it through the second and third fingers, which are in the posterior pharynx. Importantly, place the thumb under the jaw and pull the jaw forward. B, In this intubated patient, a video laryngoscope (GlideScope, Verathon, Bothell, WA) can be used to manipulate the larynx and visualize the passage of the nasogastric tube.

Ultimately, if all other methods fail, place a flexible fiberoptic bronchoscope or esophagoscope into and through the esophagus under direct visualization.³⁶ Thread a guidewire into the stomach. Place the NG tube over the guidewire into the stomach and then remove the guidewire.³⁷

Complications

Complications of standard NG tube placement are similar to the problems noted with placement of an NG feeding tube. The complications related to tube misplacement are discussed in that section. In addition, clinicians placing an NG tube in a patient with neck injuries should be cautious of potentiating cervical spine injuries with excessive motion during passage (especially in association with coughing and gagging in an awake patient). Furthermore, passage of an NG tube in an awake patient with a penetrating neck wound may exacerbate hemorrhage should coughing or gagging result. Particularly serious forms of tube misplacement are pulmonary placement (Fig. 40-10) and intracranial placement (Fig. 40-11). In confusing cases, a CT scan will clarify most misplacement issues (Figs. 40-12 and 40-13). NG tubes, when in place for prolonged periods, are a common cause of innocuous gastric bleeding and gastric erosions.

Figure 40-10 A, Levin tube inadvertently placed in the right main stem bronchus; an alveolar infiltrate consistent with early pneumonia is also shown. B, Proper position of the nasogastric (NG) tube (arrow) is best verified with a radiograph. (A, From Johnson JC. Letter to the editor: back to basics for morbidity-free nasogastric intubation. JACEP. 1979;8:289; B, from Thomsen T, Setnik G, eds. Procedures Consult—Emergency Medicine Module. Copyright 2008, Philadelphia, Elsevier Inc. All rights reserved.)

Figure 40-11 Anteroposterior and lateral skull radiographs demonstrate intracranial insertion of a nasogastric tube in a patient with multiple skull fractures. (From Johnson JC. Letter to the editor: back to basics for morbidity-free nasogastric intubation. JACEP. 1979;8:289.)

Figure 40-12 A, In this scout view of a thoracic computed tomography scan, the tip of the nasogastric tube descends only to the level of the T7 vertebrae (arrow). The stomach is overinflated with air (asterisk). B, An axial image from the neck reveals that the nasogastric tube is coiled multiple times in the pharynx (arrows) and thus never reached the stomach. Also seen is an endotracheal tube (ETT) and oropharyngeal airway (OPA).

Figure 40-13 This axial computed tomography (CT) scan at the superior thoracic level demonstrates tracheal placement of a nasogastric tube (NGT). The NGT is seen twice in the esophagus (small red arrows), which suggests that it first descended and then coiled and ascended in the esophagus. It then coiled again, turned downward, and ultimately came to rest in the trachea (large red arrow) anterior to the endotracheal tube (yellow arrow). Luckily, no oral contrast media was injected through the NGT before the CT scan.

Tension gastrothorax can develop in patients with an intrathoracic stomach. It can occupy much of the left hemithorax and thus displace the heart and lungs and cause a clinical syndrome identical to tension pneumothorax. Even though successful passage of an NG tube will relieve tension gastrothorax, the high pressures of a tension gastrothorax often develop because torsion of the stomach in the chest prevents egress of air; such torsion may also prevent ingress of the therapeutic NG tube. The condition is rare enough that further emergency therapy is based on case reports rather than substantial series. Relief of tension gastrothorax has been accomplished by transthoracic puncture of the stomach with a 16-gauge catheter-over-the-needle device inserted into the second intercostal space in the midclavicular line and then removing the needle. The catheter was left in place attached to intravenous tubing with the distal end under a water seal.³⁸ A single 16-gauge puncture of the stomach is unlikely to leak and cause pleuritis; such punctures have long been used for placement of percutaneous endoscopic gastrostomy (PEG) tubes. Inserting a chest tube into the stomach is not advisable because gastric fluid may leak into the pleural space. Once the tension on the stomach is relieved, it may be possible to pass the NG tube to prevent reoccurrence of the problem. The stomach, no longer tense and wedged in the chest, can twist to allow the tube to pass. Surgical correction of the condition permitting intrathoracic herniation of the stomach is the definitive treatment to prevent recurrence of tension gastrothorax.

Replacement of Nasoenteric Feeding Tubes

Indications and Contraindications

The most common indication for replacement of a feeding tube in the ED is unintentional removal of a preexisting feeding tube. In one prospective study, 38% of tubes were removed unintentionally. Although some of these tubes had fallen out or had been coughed out, more than half were pulled out by the patient.³⁹ Tube rupture, deterioration, or clogging may also necessitate replacement. Management of a clogged or nonirrigating feeding tube is discussed in the later section on clogged feeding tubes.

Feeding Tube Site

Three major classes of enteral feeding tubes are in common use and are classified according to the site of insertion. Tubes can enter through the nares (a cervical ostomy) or the abdomen (an abdominal ostomy). Enteral tubes are often categorized by the location of the tip of the tube. Tubes may terminate primarily in the stomach, such as a gastrostomy (G) or PEG tube (Fig. 40-14). They may terminate in the jejunum (J tube) (Fig 40-15) or in both the stomach and the small intestine (a PEG-J tube). To confuse the issue, some tubes enter the stomach and terminate in the stomach (G tube) or in the proximal part of the small bowel (J tube), whereas others enter the GI tract directly through the wall of the small bowel (J tube). Practically speaking, almost all gastric tubes are PEG tubes. They are placed endoscopically with local anesthesia and without a surgical incision. J tubes that enter the small bowel directly are inserted surgically under general anesthesia, require a surgical incision, and result in a surgical scar at the insertion site. Gastric feeding results in better digestion than intestinal feeding does. Jejunal feeding reduces reflux and aspiration.⁴⁰ Normally, about 20% of the gastric antral contents pass into the duodenum, with 80% refluxing back into the body of the stomach for further mixing, so proximal duodenal feeding is of limited benefit in preventing aspiration.^41,42 If the feeding tube is placed in the antrum of the stomach or in the small bowel, enteral feeding solution passing into the small bowel may not be tolerated and can result in diarrhea and paradoxical decreased nutrition.^41,42

Figure 40-14 Placement of a percutaneous endoscopic gastrostomy tube. A, Under conscious sedation, pass a lighted endoscope into the stomach. Indent the skin with a finger to determine the optimal puncture site where the stomach and abdominal wall are closest, with no bowel between. B, Fill a syringe with saline and advance it percutaneously to the selected entry point until the tip of the needle is seen entering from the gastric lumen through the endoscope. If air is aspirated and no needle tip is seen, the needle is in the bowel, not the stomach. C, Push and pull the scope/snare/feeding tube combination into position. D, Pull the head of the feeding tube into contact with the gastric mucosa. E, Use an external bolster or crossbar to keep the tube snug against the skin and gastric wall, but not so tight that it causes ischemia of the intervening tissue.

Figure 40-15 Formation of a Witzel tunnel and final permanent placement of a jejunal catheter. (From Wiedeman JE, Smith VC. Use of the Hickman catheter for jejunal feedings in children. Surg Gynecol Obstet. 1986;162:69.)

Procedure

The clinician should explain the procedure to the patient before passage of the tube. Replacement of a nasoenteric feeding tube requires greater time and effort if the patient is uncooperative or has a physically obstructing lesion. It is generally advisable to restrain the hands of demented, impaired, or otherwise uncooperative patients. Prepare the nares before passage of the tube similar to the procedure for primary NG tube placement. If a feeding tube stylet is used, lubricate and insert it into the feeding tube before introducing it into the naris. Tube stylets can be lubricated with water-soluble jelly. If using the Dobhoff, Entri-Flex (Biosearch), or another tube with preapplied lubricant, you may need to activate the lubricant with a 5-mL flush of water. Never allow the stylet to protrude beyond the end of the feeding tube because these stiff, small-diameter wires have the capacity to scratch the esophagus and allow the creation of a false passage. The stylet may lock into position on the tube at the proximal end and should be properly secured.

When the patient is uncooperative or cannot drink, introduce 5 to 15 mL of water into the mouth or into the proximal end of the feeding tube with a syringe; this may induce swallowing and facilitate passage of the tube. Although the patient may not swallow for several minutes, wait for swallowing because this may mean the difference between a coiled or pulmonary tube placement and successful passage.

Confirmation of Placement

Auscultatory confirmation of tube placement can be misleading, so confirm proper placement of the tube with a radiograph before feeding.³ However, radiographic confirmation of tube placement may also be misleading. In viewing the radiograph, it is particularly important to study the area around the carina. An esophageal tube shows at most a mild change in course, whereas a tracheally placed tube usually deviates significantly as it travels into the right or left main stem bronchus. The end of an NG tube may appear to be in the stomach yet may actually be in the left lung behind and below the top of the diaphragm.⁴³ When a stylet has been used for passage, leave it in the feeding tube for the radiograph because the tube’s course is not always visible without it. The stylets of most tubes are designed to allow insufflation and aspiration while in place. Even when stomach entry is certain, the intestinal location may be misleading on a radiograph. A nasoenteric tube may lie completely to the left of midline and yet have its tip in the duodenum, or it may occupy a position overlying the right side of the abdomen yet not have entered the duodenum. A contrast-enhanced study is necessary to ascertain duodenal position when pulmonary placement has been ruled out.^44,45

Examine the radiograph also for the presence of mediastinal air or pneumothorax, which may suggest pulmonary or esophageal puncture. An esophageal puncture should be evaluated with endoscopy and may require surgery, depending on the size of the rent.

The end-bulb of many nasoduodenal tubes will pass into the duodenum after positioning the patient in the right decubitus position for an hour. Some researchers recommend pretreatment with metoclopramide to enhance gastric emptying.46–48 One investigator found that metoclopramide enhances duodenal passage of nasogastrically placed feeding tubes in diabetic but not in nondiabetic patients.⁴⁴ Gastric antral motility in diabetics is often impaired; metoclopramide helps restore normal synchronized activity in these patients but has little effect on emptying in subjects with normal antral function. The usual dose of metoclopramide is 10 mg administered intravenously. Also, 3 mg/kg of erythromycin lactobionate given intravenously over a 1-hour period works similarly and may be effective even if metoclopramide fails.⁴⁹ Endoscopy or fluoroscopy may be necessary if positioning and metoclopramide are not successful.

Complications

Pulmonary intubation is an uncommon but well-known and potentially fatal complication of insertion of nasal feeding tubes (see Fig. 40-10A). Coughing and respiratory distress are the most common symptoms of respiratory passage of an NG tube, but there may be relatively few apparent symptoms in a demented or comatose patient.⁵⁰ Decreased mentation and an absent cough reflex are predisposing factors for unrecognized nasopulmonary intubation with NG tubes.³ Misplacement is far more likely in patients with ET or tracheostomy tubes, conscious or not, perhaps because tracheal stimulation by a misplaced tube is less likely to be appreciated or communicated. A small end-bulb (e.g., 2.7 mm in diameter) can slip past a tracheal high-volume, low-pressure cuff and easily pass to the periphery of the lung.^3,50–54 Pneumothorax may result when an NG tube dissects into or is withdrawn from the pulmonary parenchyma.⁵⁵ Bloody aspirate from a tube should heighten awareness of possible tissue damage.

A clogged or nonfunctional NG tube may be difficult to remove. Fluoroscopy may allow careful insertion of a guidewire or stylet into an in situ tube to facilitate removal. Fluoroscopy may also identify the mechanical problem interfering with removal of the tube. Segments bent double are probably the most common cause. Knots, though uncommon, do occur. Do not use excessive force to remove an NG tube because serious injury to the patient may result.

Premature removal of an NG tube is the most frequent complication of the use of feeding tubes. For long-term use or frequent removal of an NG tube by a patient, a gastric feeding tube will probably be inserted. To help prevent removal by an uncooperative patient, secure the NG tube to a loop anchor passed in the same naris. The anchor works by aversive stimulation of the soft palate and nose with distraction of the NG tube rather than by mechanical stabilization of the tube.

Sax and Bower recommend a technique for creating a separate NG tube anchor.⁵⁶ Cut a soft weighted nasoenteric tube approximately 12 inches from the top. Pass a heavy (2-0) silk suture through the tube to exit the side hole. Insert the guidewire with care because it must not protrude from the inserted end. Sedate the patient if uncooperative. Insert the tube through the anesthetized naris into the nasopharynx, grasp it with Magill forceps, and pull to remove it through the mouth (Fig. 40-16A). Trim excess tubing without cutting the silk suture. Make a closed loop by tying the silk suture in front of the nose. Leave the loop long enough that it does not apply continuous pressure to the nose or palate while at rest. Pass the nasal feeding tube through the same nostril and secure it to the loop (Fig. 40-16B). This anchor is simpler to construct and more comfortable than anchors that pass through the opposite nostril.⁵⁶

Figure 40-16 Placement of a nasogastric (NG) tube anchor to secure a companion NG or feeding tube in an uncooperative patient who repeatedly pulls out the feeding tube. A, Using forceps, grasp the tube in the pharynx and pull it out through the mouth. This will serve as an anchor tube. B, Tie the ends of the short anchor tube together to form a loop, and tie the companion NG or feeding tube to the anchor loop.

Complications of properly placed nasoenteric tubes include nasopharyngeal erosion, esophageal reflux, tracheoesophageal fistula, gagging, rupture of esophageal varices, and otitis media.⁵⁷ One survey of nasogastrically fed patients found that the most distressing features of having an NG tube for feeding were deprivation of tasting, drinking, and chewing of food; soreness of the nose; rhinitis; esophagitis; mouth breathing; and the sight of other patients who were eating.⁵⁸

Checking feeding tolerance is difficult with small-gauge feeding tubes. Aspiration of tubes to check for residuals is not recommended with tubes 9 Fr in size or smaller. Aspiration is likely to clog the tubes because they collapse under pressure and relatively small particles can occlude the tube. For the same reasons, the residual is likely to be inaccurate.⁵⁹

Patient or Nursing Instructions

To maintain patency of the catheter, small tubes should be flushed with 20 to 30 mL of tap water at least two to three times daily and after the administration of medication.45,59 Water is a more effective irrigant than cranberry juice.⁶⁰ Medications should be in liquid form or be completely dissolved or they may clog the tube. Methods of dealing with a clogged tube are discussed subsequently. The tube should be anchored to the nose and face in such a way that it is not in contact with the skin at the nasal opening. This reduces tube discomfort and prevents necrosis of the alae, nares, and distal septum. Patients who exhibit a tendency to pull on their tubes need adequate restraints. Patients receiving tube feedings should have their head elevated to at least 30 degrees above the horizontal.⁵⁹

Pharyngostomy and Esophagostomy Feeding Tubes

Cervical pharyngostomy and cervical esophagostomy have both been developed relatively recently. Cervical esophagostomies are generally performed at the time of cervical or maxillofacial operations. Malignant growths in the proximal part of the esophagus, head, or neck are the primary indications for esophagostomy. Cervical esophagostomies may eventually evolve into a permanent sinus, thereby allowing the feeding tube to be removed between meals. Such tubes are unlikely to be replaced in the ED, but the concept of these feeding tubes is illustrated in Figure 40-17. Complications of pharyngostomy and esophagostomy include local soft tissue irritation, accidental extubation because of excessive length of the external tube, pulmonary aspiration from vomiting, arterial erosion with exsanguination, and esophagitis or stricture of the esophagus from reflux.

Figure 40-17 A, Pharyngostomy feeding tube. B, Pathway for an esophagostomy or pharyngostomy feeding tube.

Gastroenterostomy and Jejunostomy Tubes

A nursing home patient with a nonfunctioning or displaced feeding tube represents a common ED scenario. The clinician cannot always determine the location of the original feeding tube by simply looking at a patient who arrives in the ED for replacement of the tube. Nevertheless, the emergency clinician should attempt to ensure that the terminal end of a replaced tube is in the same viscus as the original was. External inspection may or may not reveal where a feeding tube should terminate. Contrast-enhanced studies and fluoroscopy usually provide such information (Fig. 40-18). Gastrotomy tubes are available in various types (Fig. 40-19). Tubes are kept in place by either a modified end (such as a mushroom tip) or an inflatable balloon. A de Pezzer (mushroom) tube, a Corflo tube, or a Foley G tube is designed only for intragastric termination. Some tubes have two lumens, one terminating in the stomach for decompression and the other in the small bowel for feeding. These can be confused with tubes that have two entrances to one lumen (one for continuous feeding and the other for medications) and tubes that have a second lumen leading to an inflatable balloon. An original tube is not usually a Foley or balloon-tipped tube. An original PEG tube is pictured in Figure 40-20. Note that on cross section this original long tube has no balloon or port to inflate a balloon but has a mushroom end that is removed by traction.

Figure 40-18 A, Without old records, the exact type and positioning of this nonfunctioning feeding tube are unknown. The operative scar on the abdominal wall suggests an implanted tube, not a simple gastric tube. B, Injection of contrast material before removal of the tube demonstrates the tip of the tube ending in the small bowel, not the stomach. C, If the tube has been removed and questions remain about the type of tube and circumstances of placement, a new tube is best placed under fluoroscopy with guidewire assistance.

Figure 40-19 A, Various types of gastrostomy tubes. 1, Silicone catheter (American Endoscopy, Bard Interventional Products, Billerica, MA). 2, Polyurethane catheter with a collapsible foam flange (to collapse, the tube should be cut) (VIASYS MedSystems, Wheeling, IL). 3, Latex catheter with a movable external bolster and an internal mushroom or de Pezzer–type flange on the end (American Endoscopy, Bard Interventional Products, Billerica, MA). 4, Balloon (Foley) catheter (Wilson-Cook Co., Winston-Salem, NC). B, A user-friendly gastrostomy tube is supplied by VIASYS MedSystems (Wheeling, IL). The CORFLO-DUAL GT gastrostomy tube is packaged with lubricant, a prefilled syringe for inflating the balloon, and an extension set. The color-coded inflation valve indicates tube size (12 to 24 Fr). The silicone tube uses a retention balloon and a movable bolster. Note that the retention bolster is designed to prevent inward migration of the tube and not to be an anchoring device sutured to the skin. C, A gastric balloon jejunal feeding tube enters the stomach and delivers feedings into the jejunum.

Figure 40-20 A, This type of tube serves as the original percutaneous endoscopic gastrostomy (PEG) device. It has a mushroom head, not a balloon. B, When replaced, a balloon-type tube (upper tube) is used in place of the original mushroom tip tube (lower tube). C, This original tube is leaking because the mushroom tip has been pulled out of the stomach lumen and is lodged in the soft tissue of the abdominal wall. D, If the tube tract has matured (at least 2 weeks after placement), it may be removed by traction/countertraction. Significant force may be required, and be prepared for a pop and splattering of gastric contents. E, It is easy to determine whether there is a balloon at the end of a PEG tube that cannot be removed. Simply cut the tube, and if there is no additional port or channel to inflate the balloon (F), it must be the type of tube that can be removed by traction.

Foley catheters are not ideal as long-term feeding tubes. They clog easily, and the balloon disintegrates in stomach acid. They may be used temporarily but should be replaced with specialized feeding tubes when feasible (Fig. 40-21). A call from a nursing home indicating that a tube has been pulled out should be answered by the advice that a Foley catheter be used immediately to keep the stoma open. Always inflate the balloon with saline and use a bolster to prevent migration of the tube. The clinician has a few options when faced with the task of replacing a feeding tube. Unfortunately, old records or nursing home personnel rarely give specific information that is helpful to the emergency clinician. If only a stoma exists, one may request that the nursing home describe or send the prior tube to the ED. If no surgical scar is seen at the stoma site, the tube is almost certainly a G tube or a G tube that terminated in the jejunum. When in doubt, pass a Foley catheter without balloon inflation, tape it to the skin, and refer the patient to a consultant or the original referring clinician. Some type of tube must be placed to stent the stoma, or the stoma will quickly close (in a matter of hours) and the patient might require a more complicated procedure to regain access. The only real concern of placing a gastric tube into the jejunum is that the balloon will produce intestinal obstruction if it is fully inflated.

Figure 40-21 G-tube replacement (with a Foley catheter).

If the tube is nonfunctioning yet still in place, the clinician must make a judgment regarding the risk versus benefit of removal and replacement versus an attempt at unclogging the tube (see the subsequent discussion on unclogging). The major concern is that a new tube may be misplaced (i.e., into the peritoneal cavity). If it appears that a skin incision was used to place the tube, it is unlikely that the patient has an easily removable tube. If the patient has signs of a complication (e.g., infection, ileus, intestinal obstruction), surgical consultation is warranted. Note that a migrated tube, with the balloon or tube obstructing the gastric outlet, is a common cause of gastric distention, persistent vomiting, or signs of intestinal obstruction. This is easily remedied (see procedural description in “Complications” and Fig. 40-22).

Figure 40-22 A, Whenever possible, use a formal feeding tube instead of a Foley catheter. B, A common dilemma. This patient had persistent vomiting after tube feedings and gastric distention. The tube had simply migrated distally (note the comparison of the new tube and positioning of the indwelling one) because the bolster was too far proximal. Withdrawing the tube and repositioning the bolster alleviated the problem.

Most PEG tubes do not have sutures joining the stomach with the abdominal wall, so there is potential for a replaced tube to end up in the peritoneal cavity. Adhesions, however, usually keep the stomach appropriately positioned, but only after the tract has matured. Nonoperative tube replacement techniques are safe only through an established tract between the skin and the bowel. Catheter replacement should not be attempted in the immediate postoperative period. A simple gastrostomy takes about a week to form a tract.⁶¹ A stable tract may take 2 or 3 weeks longer to form if healing is compromised.

Poor nutrition is the most common element compromising wound healing in patients requiring a feeding tube. A Witzel tunnel may take up to 3 weeks after the operation to mature sufficiently for safe nonoperative tube replacement (see Fig. 40-15).

Equipment for Replacing a Dislodged Tube

Equipment for replacing a feeding tube through a matured site includes gloves, a stethoscope, a feeding tube, an external bolster, lubricant, a basin, and a syringe that fits the tube. Tincture of benzoin, tape, and absorbent dressing material may be used to dress the wound, although many are better left undressed.⁶² Some feeding tubes require special plugs or connectors. Others need to be pinched with a clamp when not in use to prevent leakage. Some tubes are placed with the aid of accompanying guidewires or stents.

The easiest tube to replace is one that has been removed in the ED or dislodged for only a few hours (Fig. 40-23). The stoma closes quite quickly, so replacement is best done as soon as possible. Gently probe the stoma site with a cotton-tipped applicator to determine patency and direction of the tract. In selected cases, a hemostat can gently dilate the opening to accept a replacement tube. Do all such attempts carefully to avoid creating a false tract. Use local anesthetic around the stoma if exploration causes pain. Bleeding is common. After the tube is passed, restrain the hands to avoid removal of the tube by uncooperative patients.

Figure 40-23 A, The feeding tube was dislodged at 11 pm, and by 9 am the stoma was too tight for easy replacement of the tube. It was accomplished under fluoroscopic guidance, always the best option in questionable cases. B, The stoma opening and direction of the tract can be investigated by gently probing the site and tract with a Q-tip; in this case it easily entered the stomach. C, This tight stoma was carefully dilated with a hemostat under local anesthesia. A false passage can easily be created, and this area usually bleeds readily. D, To give a Foley catheter sufficient rigidity to aid in passage, the end of a Q-tip was inserted in the side port of the distal end of the catheter, and traction was applied to the catheter. E, If a de Pezzer catheter is used, an endotracheal tube stylet distends the flange for passage, and the tip re-forms once in the stomach. F, This patient removed her recently replaced feeding tube, with the balloon inflated, while still in the emergency department awaiting transfer. This could have been avoided if her hands were restrained.

Removal of a Transabdominal Feeding Tube

A feeding tube may need to be removed because it is irreversibly clogged, leaking, or broken; persistently develops kinks; is too large or too small; causes a hypersensitivity reaction; is associated with an abscess; or is not the appropriate length for feeding into the desired viscus. Before a new transabdominal feeding tube is inserted, remove the old tube. Most, but not all tubes can be removed without endoscopy. It is imperative to know whether the tube in place is safe to remove before attempting to remove it. Standard de Pezzer or mushroom catheters that have been modified with bolsters or rings at the time of endoscopic or surgical insertion may no longer be safe to remove with traction. Tubes are occasionally secured with sutures or rigid internal bumpers or stays. It is rare, however, to encounter a tube that cannot be removed with traction/countertraction. Modest force may be required. Use a hand for countertraction, and be prepared for a pop and splattering of gastric contents (Fig. 40-24). This causes the tube and end mushroom to narrow, and the tube should come out easily. The inner crossbar, if present, may remain in the stomach when the rest of the feeding tube complex is removed by traction. The crossbar will pass in stool, and obstruction from it has yet to be reported in adults. In small children, obstruction is a possibility, and the crossbar should be removed by endoscopy.^63,64

Figure 40-24 Gentle, firm traction using the flat part of the opposite hand for countertraction will remove most percutaneous endoscopic gastrostomy tubes, even those with internal mushroom bumpers. Modest force may be required, and be prepared for a sudden pop and splattering of gastric contents.

Recently placed feeding tubes may need to be left in until a tract has formed (1 to 3 weeks, depending on the procedure), even if the tube is nonfunctional.

A simple Foley catheter G tube is the easiest to remove. Deflate the Foley balloon and the tube should slide right out. If the Foley balloon cannot be deflated, cut the tube to allow the balloon to deflate. Do not cut the catheter so close to the abdomen that it will be impossible to maintain a grip on it for removal by traction if the balloon still does not deflate. The balloon may also be punctured to cause it to deflate. To puncture a Foley balloon, apply traction on the catheter to draw the balloon up against the ostomy (Fig. 40-25). Using the taut feeding tube as a guide, pass a small-gauge needle along the tube to puncture the balloon. It may be necessary to try again on the other side of the catheter because the balloon may be inflated asymmetrically and contact with the needle may be established on one side and not the other. Be careful to not track away from the ostomy into the patient’s abdominal wall or to cause separate punctures of the stomach. Allow a minute for the balloon to deflate before making another attempt at removal by traction. Large, nondeflating balloons should probably be punctured, whereas small balloons may be removed with traction.

Figure 40-25 A, If a Foley balloon will not deflate, use traction to bring the balloon against the abdominal wall. Gently pass a small needle along the course of the catheter while puncturing the balloon as many times as necessary. Wait a few minutes for the fluid to egress. B, Once the balloon is deflated, it can be withdrawn. Note the encrusted condition of this long-standing Foley catheter used as a percutaneous endoscopic gastrostomy tube. C, Occasionally, the wire from a central line kit can clear the inflation lumen and allow deflation. D, If the valve mechanism malfunctions, cut the catheter and attempt to drain the balloon by placing a needle in the inflation channel and flushing and withdrawing fluid.

If it is not possible to pull the inner bolster or mushroom out through the ostomy, cut the tube at the skin, push the remaining short stump into the stomach, and rely on later rectal passage. Although obstruction or impaction is infrequent, it can occur, and this alternative has the potential to be problematic in children or patients who have had previous impaction, potential for bowel obstruction, or stool-passing problems. Rigid or large internal mushrooms and bolsters, the very kind that cause the most difficulty with percutaneous removal, are also more likely to cause difficulty with rectal passage. In no case should a device be released into the gut with a long length of tubing attached. Remember that double-part tubes may have an additional length of tubing for duodenal or jejunal feeding that extends far past the inner bolster. Korula and Harma reported successful intestinal elimination of 63 of 64 gastrostomy tubes that were cut at the skin entrance and advanced into the stomach through the stoma.⁶⁵ These cases included tubes with internal bumpers, and success occurred regardless of the nature of the patient’s underlying medical disorder, age, or method of original tube placement. However, no patient had suspected obstruction or potential for obstruction (e.g., no previous radiotherapy, inflammatory bowel disease). The one lodged tube required endoscopic removal from the pylorus. In most cases, passage of the tube was documented by sequential radiographs, with a mean interval of 24 days until passage (range, 4 to 181 days).

Some clinicians and surgeons strongly condemn cutting off the tube at the skin, even when the risks posed by the procedure are very low. It is always advisable to contact the patient’s private clinician before cutting the tube. In some cases, endoscopic retrieval of the tube remnant is preferred over allowing rectal passage, and the tube should not be cut until just before or during endoscopy to ensure that migration does not occur before endoscopy.

Securing a Transabdominal Feeding Tube

If a bolster is used, no additional means of securing the tube is necessary if the patient is not prone to pulling it out. Some clinicians tape tubes to the skin rather than using a bolster or use special adhesive devices designed to control the tube and prevent ingress, such as the Drain/Tube Attachment Device (Hollister, Inc., Libertyville, IL) or Flexi-Trak (ConvaTec, Skillman, NJ). Tape is particularly vulnerable to problems because the stress that the tape places on the skin as the tube pulls on the tape can lead to skin damage. Strong adhesive tape can also damage the skin on removal. Tape that is not sufficiently adhesive can let go, particularly if it gets wet. Because tape is less durable, home or nursing home caregivers who are less skilled may retape the tube (Fig. 40-26). If the tape is replaced at home, it may be placed under too much tension and cause thinning of the abdominal wall at the stoma. If too much slack is allowed, the tube may get pulled in. Strong tape can also damage the tube during tape changes if it comes to adhere too strongly to the tube. Special adhesive devices or bolsters are preferred.

Figure 40-26 Tape is best avoided to minimize skin maceration. If needed, this is a simple but less secure technique for securing a gastrostomy tube to the skin.

Verification of Placement

There is no universally agreed-on standard with regard to performing a confirmatory contrast-enhanced study for all easily replaced feeding tubes. Some clinicians verify position routinely with a contrast-enhanced radiograph, whereas others use the clinical criteria outlined earlier. The authors advocate radiographic verification in the majority of cases, a procedure easily performed and interpreted in the ED. Routine use of postplacement contrast-enhanced radiography to confirm proper placement should be mandatory when the tube tract is immature (i.e., <1-month duration),⁶⁶ when passage of the replacement catheter has been difficult, when the clinician is unable to aspirate intestinal contents, or when the patient is unable to communicate any symptoms that might occur with tube misplacement. Peritoneal infusion of feeding solution can be fatal.

The position of the G tube may be checked by air insufflation and aspiration of gastric fluid, as is done with nasoenteric tubes. Air should enter the stomach without resistance and should produce immediate borborygmi. Gastric fluid should return with aspiration. It may be necessary to insert a small volume of water to obtain good return. Water pooling in soft tissue may be aspirated back through a misplaced catheter. Good tube placement is indicated when more fluid returns with aspiration than was originally placed into the catheter.

Correct tube placement is easy and readily verified radiographically with a small amount of contrast material passed into the tube (Fig. 40-27). Use a catheter-tipped syringe to introduce water-soluble contrast solution (e.g., diatrizoate meglumine–diatrizoate sodium [Gastrografin]) into the tube. Barium is contraindicated because of the potential for peritoneal contamination. Inject 20 to 30 mL of water-soluble solution to document the intraluminal tube position. Take a supine abdominal film 1 to 2 minutes after instillation of dye to optimize visualization of the gut. Because the film must be obtained quickly, it is easiest to perform the injection in the radiology suite, followed by a radiograph in only a few minutes. If the contrast material does not flow freely into the tube, the procedure should be terminated immediately and the position of the tube questioned. With proper positioning, contrast material will outline the part of the gut containing the tube (e.g., stomach with a G tube). An irregular or rounded blotch with wispy edges or streamers suggests peritoneal leakage. In questionable cases, injection of dye can be performed under fluoroscopy.

Figure 40-27 A, Although this feeding tube seemed to be replaced easily in an uncommunicative nursing home patient, gastric contents could not be aspirated; therefore, a contrast-enhanced study was performed. B, Note the free flow of contrast material throughout the abdomen, especially outlining the liver (arrows). This film indicates placement of the feeding tube into the peritoneum. Placing food through this tube could be disastrous. It is prudent to routinely obtain a contrast-enhanced study after replacement of a percutaneous endoscopic gastrostomy tube in the emergency department. Instill 20 mL Gastrografin/10 mL saline into the tube and take a radiograph in 3 to 5 minutes. C, Contrast-enhanced study demonstrating correct placement of a feeding tube. Note the outline of the gastric rugae and the characteristic mucosal folds of the small intestine.

Complications

Viscus puncture, viscus–abdominal wall separation, and creation of a false tract with subsequent misplacement of the tube are risks associated with dilation procedures. Complications of gastrostomy include wound infection around the catheter, performance of an unnecessary laparotomy for suspected leakage, gastrocolic fistula, pneumatosis cystoides intestinalis, bowel obstruction, peritonitis, and hemorrhage.⁶⁴ Jejunostomies can cause most of these complications, as well as other types of fistulas and small bowel obstruction from adhesions or volvulus around the jejunostomy site.^48,67 The most common complications of gastrostomy and gastroenterostomy are local skin erosion from leakage, wound infection, hemorrhage, and dislodgment of the tube.⁵⁹ Peritonitis and aspiration are the most critical complications of gastrostomy feedings.^59,67 Jejunostomies are less prone to stomal leakage and cause less nausea, vomiting, bloating, and aspiration than do gastrostomies.^68,69

Dislodgment of G and J tubes is most common in the 2 weeks after creation of the ostomy.⁷⁰ Extrusion of the G tube is usually caused by excessive tension applied to the tube. Only gentle contact of the gastric and abdominal walls is desirable. Uncooperative patients should be restrained, and mittens are often particularly helpful. Sutures and large mushrooms or balloons do not prevent purposeful removal of the G tube by an uncooperative patient.

A small amount of drainage is to be expected at the tube entry site. Local leakage of gastric juices may macerate and irritate the skin, which can predispose the site to local infections and abscesses and encourage the development of small granulomas.68,71 Granulomas are particularly common in children. They can be treated with silver nitrate at the time of dressing changes. Any dressing used around the entry site of an enteral nutrition tube should absorb fluid and not encourage persistent moisture.⁶² An unusually large stoma may promote a leak. Although insertion of a larger tube or firmer traction on the tube might be transiently effective, these measures often result in further enlargement of the stoma. Rigid gastrostomies promote leakage by widening the stoma as they pivot. Insertion of a soft, pliant feeding tube through the widened stoma is often easy and allows later contraction of the stoma.¹ If these techniques are ineffective, temporary removal of the feeding tube may allow the stoma to shrink. Large amounts of drainage around the stoma site may occur with high residual volumes.⁷² The residual should be checked and feedings withheld until residuals are less than 100 mL. Feeding residuals should be checked every 4 hours when a patient is receiving continuous-drip feeding.⁷³

Pneumoperitoneum after percutaneous gastrostomy is neither unusual nor dangerous. Benign pneumoperitoneum may be present as long as 5 weeks after PEG.64,72 Pneumatosis cystoides intestinalis can occur through the defect in the bowel wall created for the enterostomy tube. Though often clinically insignificant, its occurrence suggests air under pressure in the small bowel. NG suction and diet change generally permit resolution of the problem. Catheter or feeding tube removal is not usually required.⁷⁴

Clinically significant pulmonary aspiration can occur with G-tube feeding. Methods of checking for silent pulmonary aspiration include assessing tracheal aspirates with a glucose oxidant reagent strip or placing methylene blue in the formula and monitoring tracheal aspirates for pigmentation.57,75,76

A Foley balloon accidentally inflated in the small bowel or esophagus can lead to perforation or obstruction.⁷⁷ Carefully inflate the balloon soon after it has entered the stomach to prevent perforation of the viscus. A G tube may migrate in the stomach and obstruct the gastric outlet. This complication is manifested clinically by vomiting and high residuals of feeding solution. Volvulus and jaundice may also occur as a result of balloon migration. To correct inward migration, first deflate the balloon. Pull the tube back just deep to its final position. Reinflate the balloon and pull it the rest of the way back into position.²⁹ The external bolster should be repositioned or one made and positioned, or inward migration will probably reoccur.^63,72 If the balloon is not deflated before repositioning, the bowel in which it is wedged may be drawn back with it, thereby preventing relief of the obstruction and possibly precipitating intussusception.

A gastrocolic fistula is usually manifested as copious diarrhea. Once it is confirmed, treatment consists of removal of the G tube. Later creation of a gastrostomy in a different location may be possible. The patient may require hospital admission for nutritional support and monitoring of fluid and electrolyte status.

An external bolster that is snugged down too tightly might result in a short stoma and embedding of the internal bolster in the abdominal wall. An abscess may result. Overly tight external bolsters should be loosened. The correct position is 1 cm from the external surface of the abdomen.

Clogged Feeding Tubes

Clogging, leaking, fracture, and kinking are problems common to all feeding tubes. Whenever feasible, replace nonfunctioning or leaking tubes with new ones. Although it may be only a temporary solution, it is prudent to attempt to unclog a tube before it is replaced, especially if the tube has a complex placement or the clinician is unsure how the tube is secured internally. Large G tubes are the least likely to clog. G tubes at least 28 Fr in size can tolerate home blenderized foods and viscous feeding solutions. Isosmotic feeding solutions are tolerated by fairly narrow tubes and cost one sixth of what elemental feedings cost. Isosmotic feedings will clog needle catheters.⁴⁶ When tube lumens are 14 Fr or smaller, all pills and the contents of all capsules should be dissolved in water to prevent obstruction of the tube.⁶²

Kinking is a frequent cause of tube blockage during the immediate period after reinsertion. Withdrawing the tube a few centimeters usually relieves the kink and obstruction. A persistently recurring kink requires removal of the tube and insertion of a fresh tube.

Accumulated feeding solution or medication precipitates are very difficult to clean or remove. Milking a pliant tube backward may remove some of the cheesy precipitates. Guidewires or stylets may clear the proximal portion of a clogged tube lumen but are unsafe to use in subcutaneous areas of the lumen because they can puncture the tube and injure the patient or create a leak in the tube. Bionix Medical Technologies supplies tube decloggers in two lengths and several diameters for clearing clogs in G and J tube (Fig. 40-28). After selecting a declogger shorter than the feeding tube, insert it gently into the tube until the end of the screw hits the clog and then rotate it clockwise to bury the end in the clog. Next, slide the declogger up and down to break up and dislodge the clog. Insertion, rotation, and sliding might have to be repeated several times until the dislodged material can be flushed into the patient with saline or water. Gravity alone should be sufficient to allow fluid to pass through the feeding tube into the patient and is a better test of successful declogging than is passage of fluid with a syringe. Theoretically, the pointed screw end of the declogger can puncture the tube, or if a declogger is put in that is too long, it may puncture the bowel or stomach directly. According to the company, no cases have been reported.

Figure 40-28 A and B, The Bionix tube declogger. Note: Two lengths and several diameters are available. Caution must be observed any time that the screw end of the declogger passes from view because the potential exists to extend or puncture out of the tube and into the patient. (A and B, Redrawn courtesy of Bionix Medical Technologies. Bionix Enteral Feeding DeCloggers are a registered trademark of Bionix Medical Technologies. www.BionixMed.com. Accessed June 21, 2012.)

Fogarty arterial embolectomy catheters can be used to unclog J and G tubes.⁷⁸ Insert the soft tip of the Fogarty catheter into the feeding tube and advance it while monitoring the insertion distance to avoid penetrating farther than the length of the feeding tube. Premeasure the allowable length of insertion. A No. 4 embolectomy catheter is suitable for a 10- or 12-Fr feeding tube, and a No. 5 embolectomy catheter is suitable for a 14-Fr feeding tube. When the catheter meets an obstruction, inflate the balloon. This usually opens the obstruction sufficiently for passage of the catheter. Once the Fogarty has been manipulated to a point just proximal to the internal feeding opening, withdraw it while gently inflating and deflating the balloon intermittently. Do not withdraw the catheter while the balloon is inflated because the catheter and feeding tube tend to move as a unit. Repeat this procedure several times if necessary. Once declogging is successful, inject contrast material to confirm the position and integrity of the tube.⁷⁸

Irrigation with carbonated beverages and high-pressure irrigation with small-volume syringes have also been recommended as techniques for unclogging feeding tubes. Although irrigation seems like a straightforward and simple solution, these techniques are generally ineffective; furthermore, the possibility exists for dangerous tube rupture with internal leakage. Broviac catheters are especially prone to tube aneurysms, which can rupture under pressure.⁷¹ Tubes unclogged by forceful irrigation or by deep luminal probing should be radiographed after injection of contrast material to check the integrity of the tube.