Enteral nutrition is the act of receiving nutrients through the gut, either orally or through an enterai access device (EAD). The use of EADs for enterai nutrition delivery has long been practiced in the hospital and the nursing home setting. Recently, the number of patients receiving home enterai nutrition (HEN) through EADs in the United States has progressively increased. The absolute numbers remain difficult to determine.
HEN has become a growing segment of the home care arena. In 1992, Medicare estimates noted that there were approximately 73,000 HEN patients resulting in an average yearly expenditure of $136 million.1 Today's expenditure estimates are very difficult to obtain, not only from the Medicare population but also for the Medicaid and private insurer populations. General consensus is that the HEN population continues to grow at a rapid rate, both in numbers and in dollars spent.
There are many common patient disease groups that make up the majority of the HEN population. This includes patients with neurologic dysfunction, upper GI cancers, anorexia, and failure to thrive. These patients, by and large, have difficulty with transfer of food from the oral cavity to the stomach. A review of the available data from 1987 to 1991 gives an excellent sample of the types of patients that were sent home receiving enterai nutrition.2 The majority of these patients had a primary cancer as the cause of their poor oral intake. The second most common group was patients with swallowing disorders, such as patients with cerebral vascular accident or with a neuromuscular dysfunction. The remainder of this group comprised a small minority of these HEN patients.
The management of HEN requires decisions that are made early on by physicians regarding enterai access, enterai formula, route of formula delivery, monitoring, complication management, and appropriateness for therapy. Careful attention must be given to each of these decisions in order to prevent complications and to ensure favorable outcomes.
EADs are the foundation for providing enterai feeding. Knowledge of these devices is imperative in order for patients to receive safe, effective enterai nutrition. In general, EADs can be broken down into 2 categories: short-term access (nasal or orally placed feeding tubes) and long-term access (percutaneous or surgically placed feeding tubes).
NASOENTERIC TUBE ACCESS
Nasoenteric tube access placement techniques have been developed for the bedside, for use with endoscopy, for use with fluoroscopy, or for placement during surgery. These techniques all have their indications, benefits, and risks. The final position of the tip of an enterai access tube is either the stomach for gastric feedings, or the jejunum for small bowel feedings. A patient who is intolerant of gastric feedings, such as a patient with gastroparesis, or a patient who has had their stomach surgically removed, will receive small bowel feedings.
Bedside nasoenteric tube placement is the most common enterai access technique used in the hospital. However, it is the least common enterai access for use in the home or long-term care environment. Either a nasogastric (NG) or nasojejunal (NJ) tube may be placed. There is very limited use of NJ tubes in the home setting because of difficulty maintaining the end of the tube in the small bowel, and therefore it will not be discussed further.
There are many techniques available for passing bedside NG tubes. Typically, an 8- to 12-Fr NG tube is passed into the stomach after the tube has been lubricated, the head is flexed, and the patient ingests sips of water to assist in passing the tube into the stomach.3 Many clinicians promote bedside auscultation with a stethoscope for confirmation of an adequate position of the NG tube. However, this can be misleading as inappropriate tube locations such as in the lung, in the pleural cavity after perforation, or coiled in the esophagus may be misinterpreted as in proper position by bedside auscultatory techniques. For this reason, every patient should have an abdominal radiograph to confirm proper position of a NG or NJ tube before initiating feedings.4
It is not unusual to be faced with a patient who is comatose and therefore unable to assist with the passage of an NG tube. In these instances, the tube can again be passed at the bedside after tube lubrication and head flexion. Auscultation of the abdominal cavity and a radiograph must be done to confirm proper tube location.
Complications of NG tube placement have been reported in up to 12% of patients5 (Table I). Early identification of these complications is important in preventing interruptions in tube feeding regimens.
The decision to use an NG tube also should warrant some very specific instructions regarding its care. The lumen of these tubes is much smaller (10-12 Fr) than a percutaneous endoscopie gastrostomy (PEG) tube (20-24 Fr), and therefore they are prone to occlusion and clogging. These tubes should be flushed after every tube feeding and medication instillation. Only liquid medications, or completely dissolved medications, should be placed through an NG tube in order to reduce the chances of tube occlusion. Care should be taken to stop tube feedings during infusion of medication such as theophylline or potassium chloride, products that are known to coagulate tube feedings and obstruct the NG tube. In general, NG tube size does not limit the type of tube-feeding formula ordered. Collier et al6 have shown that the use of a fiber-containing formula is quite safe, even through a 5-Fr feeding tube. However, the addition of a protein powder supplement to tube-feeding formulas does promote clogging in smaller-diameter NG tubes (<10 Fr).
Fixation of the NG tube to the patient's head is important for preventing NG tube migration and dislodgement. Many of these fixation devices contain an adhesive bandage that is placed across the nose. The NG tube is connected to the bandage with either an attached clip or additional adhesive. Some clinicians prefer to tape the tube to the patient's forehead. There are no randomized trials comparing different methods of NG tube fixation. Some new bridling techniques or suturing the tube to the patient's nose are discouraged because of the high risk for nasal mucosal ulc ation and tissue damage.
PERCUTANEOUS ENDOSCOPIC ENTERAL ACCESS
If a patient will require enterai access for > 1 month, endoscopie percutaneous procedures are preferred over nasoenteric access. These procedures include PEG, percutaneous endoscopie gastrojejunostomy (PEG/J), and direct percutaneous jejunostomy (DPEJ). All of these procedures require the use of conscious sedation or deep anesthesia and can be performed in the endoscopy or radiology suite, in the operating room, or at the bedside in the hospital. In comparison to nasogastric access, PEG has been shown to be a more reliable enterai access tube allowing patients to receive more calories per day because of a reduction in tube dysfunction.7
PEG
PEG was developed by Gauderer et al8 in the early 1980s. This procedure has become the standard of care for obtaining gastric access. Compared with surgical gastrostomy, PEG insertion is associated with reduced costs and morbidity. Prospective evaluations of PEG placement have found this procedure to be associated with few procedure-related complications.9 However, PEG is usually performed in patients with numerous comorbid diseases. Because of this, the survival of patients after PEG tube placement at 1 month is often only close to 40%. In 1 study, there was a reported 48% mortality at 7 days after PEG placement if the patient had prior aspiration episodes, a urinary tract infection, or was older than 75 years. This was compared with a reported 4% mortality at 7 days if none of the aforementioned risk factors were present.10
PEG outcome data. PEG may be used successfully in many disease states, but most commonly for diseases associated with dysphagia. Outcome data for PEG placement for some of the more common processes are as follows:
CANCER PATIENTS. One area of oncology in which PEG tubes are of proven benefit is in patients with head and neck cancer. The benefit of PEG tubes in this setting was illustrated in a retrospective study that had 40% (32/88) of patients receiving a PEG tube before chemotherapy and radiotherapy. The majority of these patients received home enterai feedings. Those who received a PEG lost an average of 3.1 kg compared with 7 kg of weight loss for those without a PEG. The same PEG group had significantly fewer hospitalizations for dehydration and malnutrition and had no interruption in treatment of their cancer compared with the group that did not receive PEG.11
STROKE. Data support the use of PEG tubes in those with dysphagia-associated central nervous system disorders. In 1 study, the authors reported a 1-, 8-, and 48-month survival of 78%, 35%, and 27%, respectively, after PEG placement, when the most common indication was a hemispheric stroke.12 Approximately 50% of those patients discharged from the hospital with a PEG tube poststroke will receive HEN. Most of the remaining patients will be managed in a long-term, stepdown, or rehabilitation center setting.
DEMENTIA. Dementia is a frequent disorder of the elderly and a common patient population referred for PEG. Approximately 36,000 elderly patients with dementia receive a PEG each year.13 However, the benefit of providing enterai nutrition in these patients is less clear.14 No large, randomized trials have demonstrated a difference in survival in demented patients with or without a PEG, although these trials are very difficult to construct ethically. A recent, retrospective analysis suggested there was no difference in mortality among dementia patients who did or did not receive a PEG tube.15 However, this study did not address whether the use of PEG tubes in this population for hydration and medication delivery would be appropriate. The use of PEG tube feedings for dementia patients at home or in the long-term care facility remains common.
PEG design. The PEG tube itself consists of an internal bolster, the tube lumen, an external bolster, and a feeding adaptor (Figure 1). The internal bolster prevents the PEG tube from being accidentally dislodged or "falling out" of the patient. Most internal bolsters made today are soft and designed to fold up such that these tubes can be removed with external traction (externally removable). It generally will take 8-10 lbs of external pull pressure to remove the tubes. Combative patients may also remove their own PEG tubes. Often, these combative patients will need to wear protective mittens or have an abdominal binder placed over the PEG tube site to prevent them from removing their own PEG tubes.
PEG kits are commercially available from multiple manufacturers. The most common sizes for adult patients are from 16 Fr to 24 Fr. Most tubes are made of silicone, although there are some tubes constructed out of polyurethane.
PEG postprocedure care. After initial placement, the external bolster of the PEG tube is maintained 1-2 cm from the anterior abdominal wall to avoid tissue compression and wound breakdown (Figure 2). The wound should be cleaned daily with hydrogen peroxide, and a clean dressing should be applied over the external bolster. A notched sponge or "tracheostomy" sponge is placed over the external bolster, around the tube. Dressings should not be placed under the external bolster. This will lead to extra pressure on the PEG tube wound, promoting the development of wound leakage and wound infection.
PEG tubes start to degrade or malfunction after 1-2 years, usually from yeast implantation in and degradation of the PEG tube wall/6 Once a PEG tube malfunctions, degrades, or is no longer needed, it can be removed at the bedside with a traction pull force of approximately 8-10 lbs. These PEG tubes are labeled "traction removal."17 Some PEG tubes have a stiff internal bolster and can be removed only with an endoscope. They are labeled as "endoscopie removal." Although there is an associated increase in cost with the use of endoscopie removal PEG tubes because of the need for a repeat upper endoscopy to accomplish the removal, they may be safer in patients who are confused or combative and at risk for pulling their PEG tube out after initial placement. Some authors have suggested cutting the PEG tube at the abdominal wall and allowing the internal bolster to pass through the GI tract. Unfortunately, there have been reported cases of these internal bolsters becoming retained in the small intestine, leading to a small bowel obstruction.
PEG tube replacement. Replacement PEG tubes are broadly divided into 2 categories: replacement gastrostomy tubes or low-profile devices. Replacement gastrostomy tubes usually have a balloon-type internal bolster (Figure 3). These balloon tubes can be inserted blindly through the gastrostomy site into the gastric lumen. The balloon is inflated to serve as the internal bolster. An external bolster is slid down the external tube against the abdominal wall to keep the PEG tube from migrating. There are also PEG tubes with a distensible internal bolster (Figure 4). The internal bolster is stretched with a stylet and pushed blindly through the gastrostomy site. The stylet is removed and the internal bolster assumes its previous shape. One must be careful to know the direction of the gastrostomy tube tract so that damage or rupture of the gastrostomy tract does not occur with the use of the stylet.
PEG tubes may also be replaced with low-profile gastrostomy devices (Figure 5). These devices provide a skin level access to the gastric lumen. The internal bolster may be a balloon-inflatable design or a distensible internal bolster that requires a stylet for placement. These devices come in predetermined lengths. The gastrostomy tract length must be measured in order to choose the correct length low-profile device. In order to access the device for feeding or gastric decompression, an access tube must be used to engage a valve in the top of the low-profile device. Although these tubes are cosmetically appealing, the small internal diameter of the access tubing and the valve make them more prone to valve and access tube occlusion. They are also more costly than standard balloon gastrostomy replacement tubes.
After replacement of a PEG tube with a bedside replacement PEG tube, appropriate placement within the gastric lumen must be confirmed. This can be done by a combination of auscultation of the stomach for air rapidly infused by a syringe through the PEG tube and visualization of gastric contents aspirated by an attached syringe. In questions of tube misplacement, a contrast fluoroscopic study through the PEG tube should be obtained. This is especially important when the originally placed PEG tube has been in position for 1 month or less. Early PEG tube removal may result in the stomach separating from the abdominal wall because the PEG tube tract has not completely formed. In these cases, blind, bedside PEG tube replacement may result in the replacement PEG tube being inadvertently positioned into the peritoneal cavity.
PEG complications. Complications of PEG arise more frequently in patients with comorbidities such as poor wound healing, aspiration, or coagulopathy.18-20 The most common complication is peristomal wound infection.9,18 Excessive tightening of the external bolster against the abdominal wall can cause tissue ischemia, wound leakage, and necrotizing fasciitis.21 Peristomal wound infections are often treated for 7 days with an oral antibiotic such as cephalexin in order to cover skin-related microorganisms. The infected area should also have twice-daily topical cleansing with or without antibiotic ointment. The tube should be removed in cases of worsening infection.
Major reported complications are rare and include hematoma, peritonitis, necrotizing fasciitis, gastric or colonie perforation, hepatogastric, and gastrocolic or colocutaneous fistulas. 9,19,20,22 A colocutaneous fistula is the inadvertent placement of a percutaneous feeding tube through the colon before it enters the stomach. Often, this does not become evident until the patient has their original PEG tube exchanged for a replacement tube. The replacement tube tip goes through the abdominal wall and into the colon but does not find its way from the colon into the stomach. If the enterai feedings are restarted, the patient will develop diarrhea as the tube feeding is now being infused directly into the colon. In cases of colocutaneous fistula, the tube should be removed, and the patient's condition should be monitored for appropriate closure of the fistulous tract. If the tract does not heal, surgery is warranted to repair the fistula.
A recent retrospective study by Silver et al23 focused on the experiences of older patients receiving HEN. The majority of these patients had gastrostomies. Most of these patients relied upon their families for help and had little other nursing or dietitian intervention. Onethird of the patients reported tube clogging or leaking, and one-third reported G-tube displacement. More input from a clinician regarding home enterai access care would be important in order to prevent these frequent tube-related complications.
Minor reported complications include peristomal leakage, pneumoperitoneum, fever, ileus, cutaneous or gastric ulceration, and tube extrusion or migration.9,19,22,24,25 Peristomal leakage may be resolved by holding tube feedings for a few days to reduce gastric drainage, making sure that the external bolster is not tight against the abdominal wall and protecting the patient's abdominal wall surface from the effects of acid and bile by using a skin barrier cream.
PEG tube obstruction. PEG tubes are less likely to occlude compared with nasoenteric tubes because of their larger size. However, obstructed PEG tubes may be cleared with the use of warm water and a syringe. In some cases, pancreatic enzymes mixed in a bicarbonate solution can also be effective.26 There are no data to support the use of juices, soft drinks, or meat tenderizers to unclog a PEG tube. Commercially available PEG tube cleaning brushes are also available. Flushing the PEG tube between feedings and with medication instillation will reduce the possibility of PEG tube occlusion.
PEG/J
In those patients in whom small bowel feedings are desired, endoscopic, percutaneous, small bowel access may be obtained by 2 methods. The first method, PEG/J, places a jejunal feeding tube through an existing PEG into the small bowel using an over-the-guidewire endoscopy method. After PEG placement, the patient is re-endoscoped, and a 9- or 12-Fr jejunostomy tube (J-tube) is passed over a guidewire, through the existing PEG, and into position in the small bowel (Figure 6).27 This PEG/J system allows for gastric decompression and small bowel feeding concurrently. The PEG tubes are 20-24 Fr, and the J-tubes are 9-12 Fr in size. The average longevity of the J-tube within the PEG/J system is 3-6 months.27,28
Another available gastro/jejunostomy system consists of a single tube, with a larger gastric tube molded over a smaller jejunal feeding tube. The gastric portion of the tube remains in the stomach for decompression or medication instillation. A balloon internal bolster serves as the anchoring device for the system. The jejunal portion of the tube extends down into the small intestine for feeding or instillation of liquid medications.
PEG/J management. The management of PEG/J tubes is similar to that of PEG tubes. Jejunal tubes need to be flushed aggressively to avoid clogging. Reported clogging rates of J-tubes have ranged from 3.5%35%.29,30 Semidissolved medications, bulking medications such as Metamucil (Proctor & Gamble, Cincinnati, OH), and checking J-tube residuals all lead to an increased incidence of J-tube occlusion.31 Medication may be administered through the gastrostomy tube, the larger-diameter tube. The gastrostomy tube may also be used for decompression in those with gastroparesis or gastric outlet obstruction.
Complications of PEG/J. Complications of PEG/J tubes include those already discussed for PEGs. In addition, the J-tube may experience retrograde migration or luminal dysfunction secondary to kinking or clogging. Tube migration occurs most commonly in those patients who have persistent vomiting or in instances where the J-tube was not positioned properly through the PEG tube. In instances of J-tube dysfunction, a new J-tube may be placed through the PEG into the small bowel with the use of endoscopy or fluoroscopy.
DPEJ
The second method of endoscopie jejunal access, DPEJ, directly places a J-tube into the small bowel using an endoscope, similar to the PEG technique. Good success with this procedure has been reported by Shike et al.32,33 There were some minor complications reported, including local site infection, but no reported cases of peritonitis nor bowel infarction. Because of the larger diameter of DPEJ tubes (18-24 Fr), they are less likely to occlude than the J-tubes in PEG/J systems (9-12 Fr). In addition, the J-tube does not migrate back into the stomach, as seen with the PEG/J system.
DPEJ tube management. Immediately after DPEJ placement, it may be helpful to leave the J-tube undamped for 1-2 hours so as to decompress the small bowel from the substantial amount of air that is insufflated during the procedure. Otherwise, the management is similar to that of PEG and PEG/J tubes.
DPEJ complications. Complications and technical failures have been reported in 3 retrospective series on DPEJ outcomes. Technical failure rates for placement ranged from 12% to 28%. Complications included bleeding, abdominal wall abscesses, colonie perforations, peristomal infections, enteric ulcers, and enteric leakage. Tube-related malfunctions similar to those with PEG tubes have also occurred.33-35
SURGICAL KNTERAL ACCESS
Surgical enteral access was the standard of care for many years. These procedures included gastrostomy, gastrojejunostomy, and jejunostomy. These procedures may be performed via a standard open technique or with laparoscopic guidance. In recent years, the advent of PEG, PEG/J, and DPEJ has relegated the surgical access techniques to patients who are in the operating room for another surgical procedure or patients for whom endoscopie or radiologie enterai access is technically impossible. Multiple studies have compared surgical gastrostomy to PEG. These studies have shown either a cost savings, an operative time savings, or a reduction in morbidity with PEG.36,37
Surgical jejunostomy is a procedure in which a tube is placed into the lumen of the proximal jejunum. The first person to accomplish this procedure was Bush in 1858 in a patient with a nonoperable cancer.38 In 1891, Witzel first described the most well-known technique for jejunostomy, which has subsequently undergone a number of modifications.39 The decision to place a surgical jejunostomy follows the same decision analysis as the decision to place any jejunal feeding tube. Typically, patients who are intolerant to gastric feedings, patients at high risk for aspiration of tube feedings, or patients in whom the stomach is either diseased or surgically absent will receive a surgical jejunostomy. Surgical jejunostomy is a common procedure in trauma patients. In a review by Myers et al, patients received surgical jejunostomies as an additional technique during major abdominal surgery in 95% of cases, and as the sole surgical technique in 5% of cases.29
In the standard jejunostomy, a laparotomy is performed and a proximal jejunal loop is identified. An 8-to 12-Fr silicone or rubber catheter is inserted through the abdominal wall and into the jejunum. The tube itself is sutured to the abdominal wall to keep it from migrating. Complications with this standard technique include wound infection, wound breakdown, tube occlusion, and tube dislodgment. Holmes et al30 reported a complication rate of 10% and a mortality rate of 1.4% in trauma patients receiving a surgical jejunostomy directly related to the procedure. There is limited published information regarding the outcome of surgical jejunostomy in HEN patients.
Needle catheter jejunostomy (NCJ) involves the placement of a 5- or 7-Fr catheter into the jejunum via a submucosal tunnel. It was hypothesized that this technique would have fewer complications compared with standard jejunostomy as the entrance to the jejunum was much smaller in comparison. However, the small size of the NCJ makes it prone to early occlusion and dislodgement. These catheters must be flushed aggressively. Medications, other than those available in liquid form, should not be infused via an NCJ because of its small diameter. In general, NCJs are not used for HEN.
Laparoscopic placement of J-tubes and G-tubes was developed in the early 1990s. Initially, it was proposed that these procedures were associated with less morbidity and operative stress than standard surgical jejunostomy and gastrostomy. However, it was later determined that these laparoscopic techniques did not significantly add any advantage compared with standard surgical gastrostomy or jejunostomy with relation to operative time or associated procedure morbidity.
FLUOROSCOPIC PERCUTANEOUS ENTERAL ACCESS
Percutaneous gastrostomy and gastrojejunostomy placement with fluoroscopic guidance has continued to gain acceptance since their introduction in the early 1980s.40,41 These procedures are usually performed by radiologists in the fluoroscopy suite. After topical anesthesia to the abdominal wall and occasional conscious sedation, the inferior margin of the liver is identified by ultrasound and marked on the patient's abdominal skin surface. An NG tube is passed into the stomach for insufflation. After gastric insufflation, the stomach is punctured with an introducer catheter that is pushed through the abdominal wall. Some radiologist will attach the stomach to the anterior abdominal wall with T-fasteners, whereas others will not. A guidewire is placed into the stomach through the introducer. The puncture site is serially dilated over a guidewire to a size of 10-14 Fr. A gastrostomy tube is passed over the guidewire into the stomach or into the small intestine if a gastrojejunostomy tube is desired.
This fluoroscopic approach to enterai access has excellent reported technical success.42 These procedures can be performed with minimal sedation. The major criticism of these procedures focuses on related complications. The majority of these complications involve either inadvertent puncture of contiguous abdominal organs or separation of the abdominal and gastric wall during gastrostomy tract dilation. This separation of the abdominal and gastric wall may lead to gastric leakage peritonitis.
Enteral Access Outcomes in HEN
Outcome studies of HEN patients are small in number. A study by Wilcock et al43 focused on HEN complications in 19 patients over 1 year, which is a very small study population. Enteral stomal infections frequently resulted in a visit to the physician or the healthcare worker. The same was true for the onset of diarrhea. Flatulence, although a common complaint, rarely resulted in a physician visit. They reported 14 incidents where patients could not obtain their tube feeding from their home provider, 2 cases of equipment failure, and 10 cases where the feeding tube became obstructed. Only 1 of those problems resulted in a visit to a healthcare provider.
Shattner et al44 reported on HEN use in patients with dysphagia. This was a retrospective review over the course of 8 years. The patient's nutrition therapy was followed by a nutrition support team, who also monitored their outcomes. There were 82 patients with a mean age of 61. Most of them had head and neck cancer. Most of the patients were at home receiving gastric feedings; the minority of them were home receiving small-bowel feedings. Diarrhea occurred in approximately 20% of the whole group. Tube-site stomal infection or stomal irritation and leakage comprised somewhere between 6% and 7% of the patient group.
In a preoperative head and neck cancer study, preoperative enterai nutrition support was given to a group of patients with weight loss.45 Forty-six patients received an NG tube and 43 patients received a PEG. All received HEN training. Their pretreatment weight loss was approximately 12%. On follow-up, there were no significant HEN complications. The NG-tube-fed patients only had a 15% compliance rate with NG feedings. Those who were fed with a PEG had a 68% compliance with their home tube-feeding regimen. Because of nutrition compliance issues, the PEG-fed patients had a 30% reduction in their hospital stay compared with the NG-fed patients.
CONCLUSIONS
HEN has grown significantly in its use and in new technologies. In order to provide this therapy, enterai access needs to be established. Enterai access placement techniques may involve the nurse, radiologist, endoscopist, or surgeon. The patient's current disease state, comorbidities, medical therapy, life expectancy, expected time of need of their enterai access device, and home environment will help determine the appropriate enterai access technique for tube placement (Table II). Knowledge of all enterai access devices and techniques for placement is imperative in order to provide the safest and most effective route for enterai nutrition.
