Placement of nasoenteral feeding tubes using magnetic guidance: retesting a new technique

OBJECTIVE: To study a new technique of intubating the small bowel using a newly developed nasoenteral feeding tube fitted with a magnet in its tip and guided for placement with an external magnet. METHODS: The study was performed in medical and surgical wards of a university-affiliated Department of Veterans Affairs hospital on 42 patients referred by their attending physicians for tube placement. The newly designed feeding tube was inserted per nares into the stomach using traditional technique. As the tube was advanced, movement of the hand-held steering magnet was designed to guide the tip of the magnetic nasoenteral tube along the lesser curvature of the stomach, through the pyloric sphincter, and into the duodenum. Portable abdominal radiography confirmed the anatomic location of the tube tip. RESULTS: Fifty-one intubations were performed on 42 subjects. In 45 intubations (88%), tubes passed into the duodenum. Twenty-seven (53%) met criteria for optimal placement in the second portion of the duodenum or distally. Six of 11 tubes (55%) that were not optimally placed were advanced to the distal duodenum on repositioning. Median procedure time for the initial intubations was 30 minutes (interquartile range 15-40). Median procedure time for last 10 intubations improved to 13 minutes (interquartile range 5-20). No complications were related to the procedure. CONCLUSIONS: Enteral feeding tube placement using external magnetic guidance is a promising, novel technique which is deserving of further study.     

Placement of Nasoenteral Feeding Tubes Using Magnetic Guidance: Retesting a New Technique

Objective: To study a new technique of intubating the small bowel using a newly developed nasoenteral feeding tube fitted with a magnet in its tip and guided for placement with an external magnet.

Methods: The study was performed in medical and surgical wards of a university-affiliated Department of Veterans Affairs hospital on 42 patients referred by their attending physicians for tube placement. The newly designed feeding tube was inserted per nares into the stomach using traditional technique. As the tube was advanced, movement of the hand-held steering magnet was designed to guide the tip of the magnetic nasoenteral tube along the lesser curvature of the stomach, through the pyloric sphincter, and into the duodenum. Portable abdominal radiography confirmed the anatomic location of the tube tip.

Results: Fifty-one intubations were performed on 42 subjects. In 45 intubations (88%), tubes passed into the duodenum. Twenty-seven (53%) met criteria for optimal placement in the second portion of the duodenum or distally. Six of 11 tubes (55%) that were not optimally placed were advanced to the distal duodenum on repositioning. Median procedure time for the initial intubations was 30 minutes (interquartile range 15–40). Median procedure time for last 10 intubations improved to 13 minutes (interquartile range 5–20). No complications were related to the procedure.

Conclusions: Enteral feeding tube placement using external magnetic guidance is a promising, novel technique which is deserving of further study.     

7 g weighted versus unweighted polyurethane nasoenteral tubes--spontaneous transpyloric passage and clinical performance: a controlled randomised trial

A proportion of patients requiring enteral nutrition is at increased risk of regurgitation or pulmonary aspiration of enteral diet as a result of gastric atony or paresis. The positioning of the distal end of an enteral feeding tube beyond the pylorus into duodenum or jejunum may reduce this risk. It has been postulated that by suitable lengthening of feeding tubes and by altering the distal end tip profile or by the addition of a weight, spontaneous passage of a tube through the pylorus after pernasal insertion may be achieved. In a recent controlled trial we were unable to demonstrate any advantage to a) modifying the tip profile or b) the addition of a 2.4 g weight. This prospective controlled clinical study examined the difference between an unweighted polyurethane tube which had performed optimally in the previous study and a new 7 g weighted tube similar in all other respects. In both cases less than 50% of tubes had passed spontaneously through the pylorus when assessed at 24 h, with no significant difference in performance (p = 0.38). When comparing overall length of time that each tube remained in situ, there was similarly no significant difference between the 7 g weighted and unweighted tubes (p = 0.277). We conclude that the addition of a 7 g weight to a suitably lengthened enteral feeding tube confers no advantage on either incidence of spontaneous transpyloric passage or in prolonging tube usage. If post-pyloric feeding is indicated for a patient, positioning by either fluoroscopic or endoscopic techniques should be undertaken.     

Noninvasive verification of nasogastric tube placement using a magnet-tracking system: a pilot study in healthy subjects

BACKGROUND: Fluoroscopic verification of nasogastric (NG) feeding tube placement is inconvenient and involves radiation exposure. We tested whether the position of an NG tube can be assessed reliably by a recently introduced magnet-tracking system. METHODS: A small permanent magnet was attached at the end of an NG tube and its position was monitored using an external sensor array connected to a computer. NG tube trajectory, spontaneous movements of the magnet, and its position relative to the lower esophageal sphincter (LES) and xiphisternum were assessed in 22 healthy subjects and compared with esophageal manometry. In 12 subjects, localization of the magnet was also compared with fluoroscopy. RESULTS: Magnet-tracking displayed NG tube tip movement reproducibly as it moved vertically in the esophagus and then laterally into the stomach. Compared with manometry, the accuracy and sensitivity of magnet tracking for localization of the NG tube tip, above or below the diaphragm, were 100%. Compared with fluoroscopy, the accuracy of NG tube localization by magnet tracking was 100%. With the magnet in the stomach, but not in the esophagus or LES, low amplitude displacements at a frequency of 3 per minute, consistent with gastric slow wave activity, were observed. CONCLUSIONS: Magnet tracking allows accurate, real-time, 3-dimensional localization of an NG tube with respect to anatomic landmarks. Recorded motor patterns are indicative of the position of the NG tube. Magnet tracking may be a useful tool for bedside placement of nasogastric and enteral feeding tubes.     

Formulation of enteral diets for use in jejunal enteral feeding

Nasogastric enteral feeding is not tolerated in patients with gastric atony and in many critically-ill patients in whom gastric emptying may be delayed and in whom gastro-oesophageal regurgitation may lead to pulmonary aspiration of enteral feed and the development of pneumonia. Initial attempts to overcome these problems led to the development of post pyloric enteral feeding techniques with the infusion port of the tubes positioned in the duodenum. In many centres this technique is still the most practised post-pyloric enteral feeding technique. Nasoduodenal feeding tubes often retroperistalse into the stomach. The technique of choice, therefore, in these difficult patients is to position the infusion port of the feeding tube well distal to the ligament of trietz (post ligament of trietz nasojejunal enteral tube feeding). While nasogastric and nasoduodenal enteral feeding techniques have been shown to elicit a stimulatory exocrine pancreatic response, distal jejunal enteral feeding does not. During this mode of feeding the ileal brake is activated and pancreatic exocrine pancreatic secretion inhibited by the action of the released peptide YY and glucagon-like peptide-1 hormones, in turn the inhibition of pancreatic secretion being the result of inhibition of trypsin secretion. In the light of the findings showing the absence of a stimulatory pancreatic exocrine response to nasojejunal enteral feeding these patients should receive a predigested rather than a polymeric enteral diet.     

Equal aspiration rates from postpylorus and intragastric-placed small-bore nasoenteric feeding tubes: a randomized, prospective study.

Postpylorus delivery of enteral feeding is perceived by many experts to be safer than intragastric delivery. To test this assumption, patients with similar Glasgow Coma Scores were given identical enteral formulas continuously via a 10-French nasoenteric tube, placed into the stomach or beyond the second portion of the duodenum. Observations were made for attainment of desired nutrition, bowel changes, and clinical signs of aspiration. Radiographs of the chest and abdomen were obtained every 3 days. If a tube migrated out of a chosen location, it was replaced. Thirty-three patients were studied. Seventeen patients were fed into the stomach and 16 patients were fed postpylorus. The mean duration of enteral feeding was 11.8 days for the gastric group and 10.9 days for the postpylorus group (p = NS). The time to deliver the desired kilocalories was 3.33 and 2.77 days (p = NS) for gastric and postpylorus-fed patients. Tubes displaced similarly in each group, gastric 0.647, postpylorus 0.750 per duration of feeding (p = NS). Chest radiographs met the criteria for aspiration pneumonia in 31.3% of gastric and 40% of postpylorus-fed patients (p = NS). Together, these data indicate that complications from enterally fed patients are equally common whether the distal port of the feeding tube is in the stomach or beyond the second portion of the duodenum.     

A new self-propelling nasoenteric feeding tube

A new fine-bore nasoenteric feeding tube was tested in 19 post-operative patients. It is a silicone rubber tube, which at its distal end has 5 loops with a diameter of approximately 4 cm. The loops are easily straightened during insertion into the stomach, but ease transpyloric passage after removal of the guidewire. 4 h after insertion, 18 tubes had reached the duodenum or upper part of the jejunum. In only 1 patient was there regurgitation of the tube into the stomach after insertion.     

Efficacy of erythromycin for postpyloric placement of feeding tubes in critically ill children: a randomized, double-blind, placebo controlled study

BACKGROUND: Erythromycin enhances gastric emptying and has been suggested to facilitate nasoenteric feeding tube placement in adults. Our primary objective was to evaluate the effect of erythromycin on the transpyloric passage of feeding tubes in critically ill children, and second, to evaluate the effect of erythromycin on the distal migration of duodenal feeding tubes. METHODS: Seventy-four children were randomly assigned to receive erythromycin lactobionate (10 mg/kg) IV or equal volume of saline placebo 60 minutes before passage of a flexible weighted tip feeding tube. Abdominal radiographs were obtained 4 hours later to assess tube placement. If the tube was proximal to the third part of the duodenum, two additional doses of erythromycin/placebo were administered 6 hours apart. Those receiving additional doses had repeat radiographs 14 to 18 hours after tube placement. RESULTS: The number of postpyloric feeding tubes was similar in the erythromycin and placebo treated groups 4 hours after tube insertion (23/37 vs 27/37, p = .5). Of those with prepyloric tubes at 4 hours, none in the erythromycin group and 3 in the placebo group had the tube migrate to the postpyloric position by 14 to 18 hours (p < .05). Of those with postpyloric tubes proximal to the third part of the duodenum at 4 hours, additional doses of erythromycin did not cause more tubes to advance further into the intestine than did placebo (p = .6). CONCLUSIONS: Erythromycin does not facilitate transpyloric passage of feeding tubes in critically ill children. The distal migration of duodenal tubes further into the small bowel is also not enhanced by erythromycin.     

Feeding the hypotensive patient: does enteral feeding precipitate or protect against ischemic bowel?

Although the enteral route of enteral feeding is the preferred method of nutrition support for critically ill patients, this important therapeutic strategy is not without risk. In human subjects, the digestion and absorption of nutrients induce typical hemodynamic changes, consisting of an increase in mesenteric blood flow at the expense of reduced systemic blood pressure. On rare occasion when providing aggressive enteral nutrition to critically ill patients, common symptoms of gastrointestinal intolerance may progress to a syndrome of abdominal distention, hypotension, and shock, with the development of small bowel ischemia or necrosis. Although the incidence of small bowel ischemia secondary to enteral feeding is low, the overall clinical outcome is still poor and carries a high mortality rate. Enteral feeding is well tolerated and is probably beneficial in most critically ill patients before and after a period of hypotension. Although enteral nutrition may be used with caution during the period of hypotension, evidence of poor gastrointestinal function (increased nasogastric tube output, unexplained abdominal pain, and abdominal distention), or development of dilated loops of bowel or intramural gas (pneumatosis intestinalis) on radiographic studies should be interpreted as potential indicators of gut ischemia. With progress in our understanding of the pathophysiology, diagnosis, and prevention of ischemic injury to the intestinal mucosa, the strategy of aggressive enteral feeding for critically ill patients may result in a reduction in this major complication and enhanced functional recovery from severe illness.     

Enteral feeding patients with gastric outlet obstruction

Patients with upper gastrointestinal obstructions were previously managed with gastric decompression and parenteral feeding. The authors present their experience in 50 patients with obstructions chiefly due to complicated severe acute (n = 31) or chronic cystic pancreatitis (n = 11) using a double-lumen nasogastric decompression and jejunal feeding tube system (NGJ) held in place with a nasal bridle that passes through the obstructed gastroduodenal segments, allowing distal jejunal feeding, and at the same time decompresses the stomach to prevent vomiting and aspiration. The tip of the jejunal tube was placed approximately 40 cm down the jejunum to maintain pancreatic rest. Duration of feeding ranged from 1-145 days (median 25 days); 19 patients were discharged home with tube feeds. Only 1 patient could not tolerate feeding and needed to be converted to parenteral feeding. Average tube life was 14 days, with replacement being needed most commonly for kinking or clogging of the jejunal tube (56%) or accidental dislodgement (24%). The obstruction resolved spontaneously in 60%, allowing resumption of normal eating. Of the patients with severe acute pancreatitis or pancreatic pseudocysts, pancreatic rest resulted in resolution of the disease without surgery in 87%, and need for surgery in the remainder was put off for 31-76 days. Seven patients died predominantly of complications of acute pancreatitis between 1 and 31 days. In conclusion, NGJ feeding provides a relatively safe conservative management for critically ill patients with upper gastrointestinal obstructions, reducing the need for surgery and parenteral feeding.     

Nasoenteral feeding tube insertion via fiberoptic endoscope for enteral hyperalimentation.

Total parenteral nutrition can maintain good nutritional status in selected patients. However, it can be accompanied by serious complications. It is generally agreed that enteral alimentation is more economical and safer. Gut should be used for nutritional replenishment whenever feasible. However, large-bore nasogastric feeding tubes can cause problems. Even fine-bore nasogastric tubes can cause aspiration pneumonia in obtunded and debilitated patients. In some patients it is clearly desirable to have the tip of the feeding tube in the distal duodenum or proximal jejunum. Previously described methods for placement of nasoenteral tubes may be unsatisfactory. We describe a safe, simple, and reliable method for endoscopic insertion of fine-bore nasoenteral feeding tube. We have used this method on 15 patients without complication.     

Transnasal endoscopic placement of nasoenteric feeding tubes: outcomes and limitations in non-critically ill patients.

Transnasal endoscopic placement of nasoenteric tubes (NETs) has been demonstrated to be useful in the critical care setting, with limited data on its role in non-critically ill patients. The authors collected data on consecutive patients from a non-critical care setting undergoing transnasal endoscopic NET placement. All NETs were endoscopically placed using a standard over-the-guidewire technique, and positions were confirmed with fluoroscopy. Patients were monitored until the removal of NETs or death. Twenty-two patients (median age = 62.5 years, 36.4% female) were referred for postpyloric feeding, with main indications of persistent gastrocutaneous fistula (n = 6), gastroparesis or gastric outlet obstruction (n = 5), duodenal stenosis (n = 6), acute pancreatitis (n = 4), and gastroesophageal reflux after surgery (n = 1). Postpyloric placement of NET was achieved in 19 of 22 (86.3%) patients, with 36.8% tube positions in the jejunum, 47.4% in the distal duodenum, and 15.8% in the second part of the duodenum. NET placement was least successful in cases with duodenal stenosis. NETs remained in situ for a median of 24 days (range, 2-94), with tube dislodgement (n = 3) and clogging (n = 5) as the main complications. NET feeding resulted in complete healing of gastrocutaneous fistulae in 5 of 6 patients and provision of total enteral nutrition in 3 of 4 cases of acute pancreatitis and 9 of 11 cases of gastroparesis or proximal duodenal obstruction. Transnasal endoscopy has a role in the placement of NET in non-critically ill patients requiring postpyloric feeding. However, there are some limitations, particularly in cases with altered duodenal anatomy.     

Small bowel feeding tube placement using an electromagnetic tube placement device: accuracy of tip location

Background: An electromagnetic tube placement device (ETPD) monitors tip position of feeding tubes (FT) during placement in the digestive tract. It helps to avoid airway misplacement and permits positioning into the small bowel (SB). This study compares the overall agreement between FT tip location as determined by an ETPD vs an abdominal radiograph of the kidneys, ureter, and bladder (KUB). Methods: Using an ETPD, A nurse placed postpyloric FTs in ICU patients. We included all patients in whom the ETPD was used for FT placement. Data were prospectively recorded for 255 days on the rate of successful postpyloric placement, ETPD estimated tip location, and KUB location. Results: 860 tubes were placed in 616 patients, 719 (83.6%) of which recorded for ETPD and KUB. According to the KUB, 81% of tubes were in the SB; however, ETPD suggested 89% were beyond the pylorus. There was moderate agreement beyond what could be attributed to chance between KUB and ETPD tip locations (475 [66.1%], κ score 0.62 [95% confidence interval 0.58–0.67]). More tubes by KUB were distal (134[18.6%]) vs proximal (110[15.3%]) to the suspected location by ETPD (P < .0001. Tubes in or distal to the second half of the duodenum, according to ETPD were rarely in the stomach (<1%). No tubes were proximal to the stomach or placed into the airway. Conclusions: The strong agreement between KUB and ETPD, when tubes were believed to be in the second part of the duodenum or beyond, suggests that KUB is necessary only when the FT tip is suspected to be in the proximal duodenum.     

A randomized controlled trial comparing three different techniques of nasojejunal feeding tube placement in critically ill children

BACKGROUND: The goal of this study was to compare 3 different techniques used to place nasojejunal (NJ) feeding tubes in the critically ill or injured pediatric patients. This was a randomized, prospective trial in a university-affiliated 12-bed pediatric intensive care unit. Patients were critically ill children requiring placement of an NJ feeding tube. Patient age, weight, medications, use of mechanical ventilation, and patient tolerance were recorded. An abdominal radiograph obtained immediately after the placement determined correct placement. The final placement was recorded, as was the number of placement attempts. METHODS: Patients were randomized to 1 of 3 groups: standard technique, standard technique facilitated with gastric insufflation, and standard technique facilitated with the use of preinsertion erythromycin. To ensure equal distribution, all patients were stratified by weight (<10 kg vs > or =10 kg) before randomization. All NJ tubes were placed by one of the investigators. If unsuccessful, a second attempt by the same investigator was allowed. Successful placement of the NJ tube was defined by confirmation of the tip of the tube in the first part of the duodenum or beyond by a pediatric radiologist blinded to the treatment groups. RESULTS: Seventy-five pediatric patients were enrolled in the study; 94.6% (71/75) of tubes were passed successfully into the small bowel on the first or second attempt. Evaluation of the data revealed no significant association with a specific technique and successful placement (p = .1999). CONCLUSIONS: When placed by a core group of experienced operators, the majority of NJ feeding tubes can be placed in critically ill or injured children on the first or second attempt, regardless of the technique used.     

Relationship between feeding tube site and respiratory outcomes

Background: It is unclear if placing feeding tubes postpylorically to prevent respiratory complications is worth the extra effort. This study sought to determine the extent to which aspiration and pneumonia are associated with feeding site (controlling for the effects of severity of illness, degree of head‐of‐bed elevation, level of sedation, and use of gastric suction). Methods: A retrospective analysis was performed on a large data set gathered prospectively to evaluate aspiration in critically ill, mechanically ventilated patients. Feeding site was designated by attending physicians and confirmed by radiography. Each patient participated in the study for 3 consecutive days, with pneumonia assessed by the simplified Clinical Pulmonary Infection Score on the fourth day. Tracheal secretions were assayed for pepsin in a research laboratory; the presence of pepsin served as a proxy for aspiration. A total of 428 patients were included in the regression analyses performed to address the research objectives. Results: As compared with the stomach, the percentage of aspiration was 11.6% lower when feeding tubes were in the first portion of the duodenum, 13.2% lower when in the second/third portions of the duodenum, and 18.0% lower when in the fourth portion of the duodenum and beyond (all significant at P < .001). Pneumonia occurred less often when feedings were introduced at or beyond the second portion of the duodenum (P = .020). Conclusions: The findings support feeding critically ill patients with numerous risk factors for aspiration in the mid‐duodenum and beyond to reduce the risk of aspiration and associated pneumonia.     

Pleural complications of nasoenteric feeding tubes

Pliable, small-bore, feeding tubes are inserted frequently in critically ill patients. The use of wire stylets to facilitate passage of these tubes has increased the chances of unrecognized tracheal intubations, particularly in obtunded patients. Five patients with depressed sensoria had inadvertent transbronchial insertions of feeding tubes into their pleural spaces over a 28-month period. The incidence of this complication among intensive care unit patients was 0.3%. Sequellae included pneumothoraces in four patients, pleural effusions in three patients, and pneumonia with a pulmonary abscess in one patient. The presence of cuffed endotracheal tubes did not prevent this complication in patients with depressed cough reflexes. Inexperience of feeding tube insertors may have contributed to pleural intubations in four of the patients. In patients with depressed sensoria, adequate confirmation of feeding tube location in the stomach or duodenum requires both chest and abdominal roentgenograms.     

Post‐pyloric feeding tube placement in critically ill patients: Extending the scope of practice for Australian dietitians

Aim

To determine whether the placement of a post‐pyloric feeding tube (PPFT) can be taught safely and effectively to a critical care dietitian.

Methods

This is a prospective observational study conducted in an adult intensive care unit (ICU). The intervention consisted of 19 attempts at post‐pyloric intubation by the dietitian. The 10 ‘learning’ attempts were performed by the dietitian under the direction of an experienced (having completed in excess of 50 successful tube placements) user. A subsequent nine ‘consolidation’ attempts were performed under the responsibility of the intensive care consultant on duty. The primary outcome measures were success (i.e. tip of the PPFT being visible in or distal to the duodenum on X‐ray) and time (minutes) to PPFT placement. Patients were observed for adverse events per standard clinical practice.

Results

A total of 19 post‐pyloric tube placements were attempted in 18 patients (52 (23–70) years, ICU admission diagnoses: trauma n = 4; respiratory failure n = 3; and burns, pancreatitis and renal failure n = 2 each). No adverse events occurred. Most (75%) patients were sedated, and mechanically ventilated. Prokinetics were used to assist tube placement in 11% (2/19) of attempts, both of which were successful. Placement of PPFT was successful in 58% (11/19) of attempts. Whilst training, the success rate was 40% (4/10) compared with 78% (7/9) once training was consolidated (P = 0.17). In the successful attempts, the mean time to placement was 11.0 minutes (3.9–27.1 minutes).

Conclusions

A dietitian can be trained to safely and successfully place PPFT in critically ill patients.     

Factors causing interrupted delivery of enteral nutrition in trauma intensive care unit patients.

BACKGROUND: The intent of this study was to ascertain the adequacy of delivery of enteral nutrition (EN) to critically ill adult multiple trauma patients and to identify potential detrimental factors that affect EN delivery. METHODS: Retrospective observational study. Trauma intensive care unit (TICU) in a university-affiliated hospital. Adult patients (>/=18 years of age) admitted to the TICU who received enteral feeding. RESULTS: Fifty-six adult patients were enrolled for study. Patients received, on average, 67% +/- 19% of what was prescribed for 5.7 +/- 2.0 days. A total of 222 occurrences for temporary discontinuation of tube feeding were identified. Gastrointestinal intolerance, as defined by a gastric residual volume of >150 mL, abdominal pain, or >3 liquid stools per day, accounted for only 11% of the occurrences for discontinuation of feeding. Surgery (27%) and diagnostic procedures (15%) represented the majority of reasons for inadequate nutrient delivery. Minor factors for EN interruptions were mechanical feeding tube problems (8%), pharmacy delivery delay (4%), and miscellaneous factors (3%). Multiple and unknown reasons contributed to 14% and 18% of the occurrences, respectively. CONCLUSIONS: Surgery and diagnostic procedures accounted for the largest factor in enteral feeding discontinuations in our critically ill trauma patients. Gastrointestinal intolerance contributed a minor role in the temporary discontinuation of enteral feeding.     

Serum paracetamol concentration: an alternative to X-rays to determine feeding tube location in the critically ill

BACKGROUND: Placement of enteral feeding tubes is an important clinical issue. Previous studies suggest that paracetamol absorption is very fast after jejunal administration. The aim was to determine whether paracetamol serum concentration measured by immunoassay can determine the tip position of the feeding tube. METHODS: Thirty-three critically ill patients requiring enteral nutrition with either gastric or post-pyloric feeding tubes were enrolled prospectively in the surgical intensive care unit of a university hospital. Paracetamol was administered in the feeding tube (15 mg/kg) after a baseline blood sample (T0). Thereafter, 8 blood samples were taken between 2.5 and 240 minutes. Paracetamol was analyzed using an automated homogenous immunoassay. RESULTS: The patients did not differ with respect to age or severity of disease. Peak paracetamol concentrations were significantly higher after post-pyloric administration with 42.6 +/- 13.5 versus 20.5 +/- 7.5 mg/L (p < .0001). Time-to-peak paracetamol concentration was significantly shorter with post-pyloric tubes (median, 5 versus 60 minutes; p < .0001). The receiver operating characteristic (ROC) curves showed the highest sensitivity and specificity at 5 minutes with 94.1% and 100%, respectively, for discriminating between gastric and post-pyloric location. CONCLUSIONS: Because of paracetamol's rapid absorption after jejunal administration, the test seems to be a safe and inexpensive alternative to X-ray control for assessment of the enteral feeding tube location. Its value in clinical practice remains to be established.     

Enteral access in mechanically ventilated patients.

The early institution of enteral nutrition is now accepted as the preferred route of feeding in critically ill patients with a functioning gastrointestinal tract. It is particularly important to establish early enteral nutrition in mechanically ventilated patients because of the metabolic demands associated with mechanical ventilation. The options for enteral access in mechanically ventilated patients are reviewed, with an emphasis on those techniques that may be performed at the bedside. The advantages, disadvantages, and complications of the different techniques will be considered.