超声辅助四步法鼻空肠管置入在ICU中的应用

目的:探讨超声辅助四步法鼻空肠管置入在ICU重症病人中的应用价值。方法:33例拟行肠内营养支持的ICU重症病人采用超声引导四步法进行鼻空肠管置入,即通过超声判断鼻空肠管置入食道内、鼻空肠管置入胃内、鼻空肠管置入幽门后、最后确认鼻空肠管位置。结果:成功置入28例,失败3例,失败原因为通过幽门之假象及病人胃蠕动消失,鼻空肠管末端贴于胃大弯处,无法弯曲进入胃窦、幽门。结论:超声辅助四步法床旁鼻空肠管置入技术是一种新的鼻空肠管置入技术,操作简单,有效、无创,可重复性且成功率较高,可预防或减少并发症的发生。     

Spontaneous transpyloric passage and performance of 'fine bore' polyurethane feeding tubes: a controlled clinical trial

Certain groups of patients requiring enteral nutritional support are at increased risk of regurgitation and pulmonary aspiration of feed. Positioning of enteral feeding tubes distal to the pylorus has been advocated as a method of reducing such complications. Various techniques have been suggested to achieve postpyloric siting. Reports have indicated that lengthening the tube or altering the distal end tip configuration, by varying the tip profile or by the addition of a weight, may facilitate spontaneous transpyloric passage of the tube. This prospective controlled clinical study using three new polyurethane tubes demonstrates that the frequency of spontaneous transpyloric passage of the tube is not affected by tip profile or by the addition of a weight. Indeed, with all three tube designs only about one-third had passed spontaneously through the pylorus at 24 hr. Once through the pylorus the unweighted tube stayed in position significantly longer than the weighted tubes (p less than 0.005). We suggest that in those patients requiring post-pyloric feeding, endoscopic or fluoroscopic techniques should be used to position the tubes at the time of insertion, and that an unweighted tube should be used to prolong tube usage.     

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.     

Endoscopic placement of fine bore nasogastric and nasoenteric feeding tubes

In a small proportion of patients requiring enteral nutrition it may not be possible to site nasogastric or nasoenteric feeding tubes using standard intubation techniques. We describe an endoscopic method of tube placement applicable not only for positioning nasogastric feeding tubes in patients with coexisting oesophageal pathology, but also for placement of nasoenteric feeding tubes when disordered gastric emptying is present.     

Enteral access for nutrition in the intensive care unit

PURPOSE OF REVIEW: Enteral nutrition is the preferred route for nutrition support in the intensive care unit setting. This is usually delivered through nasoenteric feeding tubes in patients with an otherwise functional gastrointestinal tract. Placement of nasoenteric feeding tubes, however, may be difficult in this setting. Nasoenteric feeding tubes may be placed by multiple methods, each with their particular advantages and disadvantages. This review summarizes the recent literature on different methods of nasoenteric feeding tube placement with emphasis on critically ill patients. RECENT FINDINGS: Bedside assisted methods using electromyogram, electrocardiogram, and magnetic fields to provide immediate positional feedback to help guide tube advancement appear promising. Bedside methods using specific protocols, modified feeding tubes, prokinetics or magnetic assistance were also successfully reported. None of these methods has been prospectively compared with more commonly practiced methods in large studies. Endoscopic nasoenteric tube placement methods including transnasal approaches using ultra-thin endoscopes have been recently described and appear to be equivalent to fluoroscopic placement. All these recently reported techniques, however, may require more specialized equipment or training than is currently widely available. SUMMARY: Feeding tubes can be placed using bedside, fluoroscopic, and endoscopic means. Novel bedside methods have been recently described using immediate positional feedback or new assistive methods. Endoscopic techniques have similar success rates to fluoroscopic techniques and provide data on upper gastrointestinal abnormalities. There is no clear universal standard method. When feeding tube placement is required the technique used depends on local institutional resources and expertise.     

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.     

Use of small-bore feeding tubes: successes and failures

PURPOSE OF REVIEW: Early enteral nutrition is the preferred option for feeding patients who cannot meet their nutrient requirements orally. This article reviews complications associated with small-bore feeding tube insertion and potential methods to promote safe gastric or postpyloric placement. We review the available bedside methods to check the position of the feeding tube and identify inadvertent misplacements. RECENT FINDINGS: Airway misplacement rates of small feeding tubes are considerable. Bedside methods (auscultation, pH, aspirate appearance, air bubbling, external length of the tube, etc.) to confirm the position of a newly inserted small-bore feeding tube have limited scientific basis. Radiographic confirmation therefore continues to be the most accurate method to ascertain tube position. Fluoroscopic and endoscopic methods are reliable but costly and are not available in many hospitals. Rigid protocols to place feeding tubes along with new emerging technology such as CO2 colorimetric paper and tubes coupled with signaling devices are promising candidates to substitute for the blind placement method. SUMMARY: The risk of misplacement with blind bedside methods for small-bore feeding tube insertion requires a change in hospital protocols.     

Bedside placement of small bowel feeding tubes in hospitalized patients: a new role for the dietitian

OBJECTIVE: The benefits of enteral nutrition when compared with parenteral nutrition are well established. However, provision of enteral nutrition may not occur for several reasons, including lack of optimal feeding access. Gastric feeding is easier to initiate, but many hospitalized patients are intolerant to gastric feeding, although they can tolerate small bowel feeding. Many institutions rely on costly methods for placing small bowel feeding tubes. Our goal was to evaluate the effectiveness of a hospital-developed protocol for bedside-blind placement of postpyloric feeding tubes. METHODS: The Surgical Nutrition Service established a protocol for bedside placement of small bowel feeding tubes. The protocol uses a 10- or 12-French, 110-cm stylet containing the feeding tube; 10 mg of intravenous metoclopramide; gradual tube advancement followed by air injection and auscultation; and an abdominal radiograph for tube position confirmation. In a prospective manner, consults received by the surgical nutrition dietitian for feeding tube placements were followed consecutively for a 10-mo period. The registered dietitian recorded the number of radiograph examinations, the final tube position, and the time it took to achieve tube placement. RESULTS: Because all consults were included, feeding tube placements occurred in surgical and medical patients in the intensive care unit and on the ward. Of the 135 tube placements performed, 129 (95%) were successfully placed postpylorically, with 84% (114 of 135) placed at or beyond D3. Average time for tube placement was 28 min (10 to 90 min). One radiograph was required for 92% of the placements; eight of 135 (6%) required two radiographs. No acute complications were associated with the tube placements. CONCLUSIONS: Hospitalized patients can receive timely enteral feeding with a cost-effective feeding tube placement protocol. The protocol is easy to implement and can be taught to appropriate medical team members through proper training and certification.     

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.     

A randomized trial of endoscopic and fluoroscopic placement of postpyloric feeding tubes in critically ill patients

BACKGROUND: Early postpyloric feeding is considered the accepted method of nutrition support in critically ill patients. Endoscopic and fluoroscopic techniques are associated with the highest percentage of successful placement. The purpose of this study was to compare endoscopic vs fluoroscopic placement of postpyloric feeding tubes in critically ill patients. METHODS: This is a randomized prospective clinical trial. Forty-three patients were randomized to receive feeding tubes by endoscopic or fluoroscopic technique. All procedures were performed at the bedside in the critical care unit. A soft small-bore nonweighted feeding tube was used in all cases. Successful placement was confirmed by either an abdominal x-ray for endoscopic technique or a fluoroscopic radiograph for fluoroscopic technique. RESULTS: Postpyloric feeding tubes were successfully placed in 41 of 43 patients (95%). The success rate using endoscopic technique was 96% (25 of 26), whereas the rate using fluoroscopy was 94% (16 of 17). The average time of successful placement was 15.2 +/- 2.9 (mean +/- SEM) minutes for endoscopic placement and 16.2 +/- 3.2 minutes for fluoroscopic placement, which was not statistically significant (p > .05). CONCLUSIONS: Endoscopic and fluoroscopic placement of postpyloric feeding tubes can safely and accurately be performed at the bedside in critically ill patients. Our results showed no significant difference in the success rate or time of placement between endoscopic vs fluoroscopic placement of postpyloric feeding tubes.     

Placement of a Magnetic Small Bowel Feeding Tube at the Bedside

Background: Current methods of achieving postpyloric enteral access for feeding are fraught with difficulties, which can markedly delay enteral feeding and cause complications. Bedside tube placement has a low success rate, often requires several radiographs to confirm position, and delays feeding by many hours. Although postpyloric enteral tubes can reliably be placed in interventional radiology (IR), this involves greater resource utilization, delays, cost, and inconvenience. We assessed the utility of bedside enteral tube placement using a magnetic feeding tube (Syncro‐BlueTube; Syncro Medical Innovations, Macon, GA, USA) as a means to facilitate initial tube placement. Methods: We recorded the time to insertion, location of tube, success rate, and need for radiographs in a series of patients given magnetic feeding tubes (n = 46) inserted by our hospitalist service over an 8‐month interval. Results: Of the 46 attempted magnetic tube placements, 76% were successfully placed in the postpyloric position, 13% were in the stomach, and 11% could not be placed. In 83% of the magnetic tubes, only 1 radiograph was needed for confirmation. The median time to placement was 12 minutes (range, 4–120 minutes). Conclusion: The use of a magnetic feeding tube can increase the success rate of bedside postpyloric placement, decrease the time to successful placement, and decrease the need for supplemental radiographs and IR.     

Verification of an electromagnetic placement device compared with abdominal radiograph to predict accuracy of feeding tube placement

Background: Use of an electromagnetic placement device (EMPD) facilitates placement of feeding tubes at the bedside. Standard practice for verification of feeding tube placement is via radiographic confirmation. The purpose of this research study was to assess the accuracy of placement of small‐bore feeding tubes (SBFTs) as determined by EMPD interpretation compared with that of abdominal radiograph verification by a radiologist. Methods: This multicenter prospective study enrolled patients requiring bedside feeding tube placement. SBFTs were placed by an experienced investigator using the EMPD. Two abdominal radiographs were then obtained: one after initial SBFT placement and an additional radiograph after injection of contrast. Documentation of location based on clinician interpretation using the EMPD was then compared with radiologist interpretation. Results: The final sample size was 194 patients, including 18 pediatric patients. Patient age ranged from 12 days to 102 years. Median time for tube placement was 12 minutes. Of the 194 patients, only 1 patient had data showing discrepancies between the original EMPD verification and the final abdominal radiograph interpretation, providing a 99.5% agreement. No patient experienced complications during SBFT placement, and 15 patients had inadvertent airway placement that was avoided with the use of the EMPD. Conclusions: There was a high percentage of agreement between EMPD and radiologic interpretation after contrast injection. The EMPD aided in avoiding inadvertent airway placement, with no patient complications. This device can be used safely at the bedside to facilitate placement of feeding tubes, leading to the delivery of early enteral nutrition.     

X线下放置鼻空肠营养管在危重症早期肠内营养中的应用

目的:探讨X线下放置鼻空肠营养管,在危重症病人早期肠内营养中的临床应用价值.方法:在X线监视下,将带有金属导丝的营养管自鼻腔经胃、十二指肠,置入空肠,拔出导丝,注入造影剂,确认营养管前端已进入Treitz韧带后30 cm以远.结果:X线下可将营养管放置至Treitz韧带30 cm以远的空肠部位,置管成功率为100%,置管时间为10～40(平均20)min.置管后营养管在位良好,喂养过程顺利.结论:X线下放置鼻空肠营养管,是一种操作简便快捷、安全可靠的置管技术,为危重症病人早期肠内营养支持提供了一条更有效的营养途径.     

胃镜辅助下放置空肠营养管的方法

目的:探讨内镜下放置空肠营养管的方法.方法:给148例病人放置空肠营养管,116例病人在胃镜下用异物钳钳夹胃腔内空肠营养管,推送胃镜将其送至Treitz韧带以下.32例经鼻超细胃镜放置导丝后,再经导丝放入空肠营养管.结果:两种空肠营养管放置成功率均为100%,其中鼻肠管126例,三腔鼻肠管22例.两组均无严重并发症,1例病人置管后出现血淀粉酶升高.结论:两种空肠营养管放置的方法成功率均高,不良反应小,操作简单安全.     

Monitoring feeding tube placement.

The purpose of this literature review is to describe currently available bedside methods to determine feeding tube placement. Described first are methods used at the time of blind insertion to distinguish between gastric and respiratory placement and gastric and small-bowel placement. Discussed next are methods used after feedings are initiated to determine if the tube has remained in the desired position in the gastrointestinal tract. Some of the methods are research-based, whereas others are opinion-based. The level of accuracy of the methods discussed in the review varies widely. No sure non-radiographic method exists to differentiate between respiratory, esophageal, gastric, and small bowel placement of blindly inserted feeding tubes in the fed or unfed state. However, a combination of some of the simpler and more accurate methods may be used to guide feeding tube placement during insertion and help identify the point at which an abdominal radiograph is most likely to confirm the desired location. In addition, methods described in this review can help determine when a radiograph is needed to confirm that a feeding tube has remained in the correct position after the initiation of feedings. Minimizing the number of radiographs taken to assure correct tube placement is important, especially in young children and in the critical care setting where the need for radiographs for other reasons is common.     

When Does Metoclopramide Facilitate Transpyloric Intubation?

Postpyloric feeding probably reduces the incidence of tracheobronchial aspiration and improves feeding tolerance. However, duodenal intubation is often unsuccessful in critically ill patients due to gastric atony. Metoclopramide improves gastric emptying. In a pilot study, 12 adult patients were administered 10 to 20 mg of intravenous metoclopramide after weighted nasal feeding tubes had failed to spontaneously pass distal to the pylorus. In no patient did metoclopramide induce transpyloric passage of the tube. A randomized prospective study involving 10 adult patients was conducted to examine the effect of preinsertion intravenous metoclopramide on transpyloric intubation. All patients had failed to achieve spontaneous duodenal intubation. Five patients received 20 mg of metoclopramide 10 min prior to nasal insertion of a weighed feeding tube. Five control patients received no premedication. Four metoclopramide patients achieved duodenal intubation immediately. In none of the control patients did transpyloric intubation occur (p = 0.048). Metoclopramide, administered after nasogastric intubation, is ineffective in promoting transpyloric advancement of feeding tubes. There is a significant increase in transpyloric intubation when metoclopramide is administered prior to tube insertion.     

Technique for intraduodenal placement of transnasal enteral feeding catheters.

Timely initiation of enteral feeding requires efficient placement of nasoenteric feeding tubes. It is generally agreed that postpyloric placement of feeding tubes reduces the risk of regurgitation and aspiration of feeding formulas. The authors describe a simple, economic method of achieving postpyloric placement of feeding tubes in most patients.     

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.     

Bedside placement of nasojejunal tubes: a randomised-controlled trial of spiral- vs straight-ended tubes

BACKGROUND AND AIMS: The success rate of unguided nasojejunal feeding tube insertion is low, thus often requiring endoscopic or radiological assistance. The spiral end of the Bengmark nasojejunal tube is supposed to aid post-pyloric placement, but no comparative trial has been performed. METHODS: Patients requiring nasojejunal feeding were randomised to have either Medicina (straight) or Bengmark (spiral) nasojejunal tube placed after stratification into those with normal gastric emptying or clinical evidence of delayed gastric emptying. Nasojejunal tubes were placed at the bedside in a standard fashion without radiological guidance by the same person for pre- and/or post-operative feeding. Bolus intravenous metaclopromide (10mg) was given prior to insertion in the abnormal gastric emptying group. Abdominal radiographs were obtained at 4 and 24h, and the primary end-point was jejunal placement at 24h. RESULTS: Forty-seven patients were randomised of which 17 (11 straight, 6 spiral) could not tolerate the nasojejunal tube. Of the 30 remaining patients, 16 had normal gastric emptying. In patients with normal gastric emptying, successful placement at 24h was achieved in 78% (spiral tube), vs 14% (straight tube) (P=0.041). In the abnormal gastric emptying group, success rates were 57% and 0%, respectively (P=0.07). CONCLUSION: Spiral nasojejunal tubes are preferable to straight tubes for bedside unguided post-pyloric feeding in patients with normal gastric emptying.