Electromagnetic- or endoscopic-guided methods: which works better for placement of a feeding tube into the small bowel?

Key messages

- Due to a lack of robust evidence, it is unclear whether electromagnetic-guided placement is superior to endoscopic-guided placement when placing feeding tubes in the small intestine.
- Electromagnetic-guided placement of feeding tubes probably costs less than endoscopic-guided placement.

Background

The use of a feeding tube to deliver nutrition via the intestine is important for treating people who are unhealthy, malnourished, or both, and who have a functioning bowel but are unable to eat. For people who are at high risk of food or liquid entering the airway (which can cause pneumonia, an inflammatory condition of the lungs), a feeding tube can be used to help nutrition and medicines reach the small intestine. Both methods for placing a feeding tube involve passing the tube through the nose, oesophagus (food pipe), stomach, and into the small intestine (gut) via a guidewire. Although endoscopic-guided placement – using a thin, flexible tube with a camera – is the most common way to pass a feeding tube to reach the small intestine, multiple medical professionals must confirm its successful placement in the x-ray department, rather than at a person's bedside. In contrast, a trained nurse using a computer screen can perform electromagnetic-guided placement of the feeding tube, as well as confirm its successful placement, at a person's bedside. 

What did we want to find out?

We wanted to find out whether electromagnetic-guided placement or endoscopic-guided placement of a feeding tube into the small bowel is better and safer for people who are unhealthy and unable to eat.

What did we do?

We searched for studies that compared electromagnetic-guided placement with endoscopic-guided placement of feeding tubes through the nose. We compared and summarised the results of the studies and rated our confidence in the evidence, based on factors such as study methods and sizes. We investigated how successful doctors were at placing feeding tubes to reach the small intestine at the first attempt and the proportion of people in the studies with pneumonia. In addition, we evaluated the time it took to place feeding tubes into the small bowel using the two different methods, the costs, and any unwanted, harmful events.

What did we find?

We found four studies involving 541 participants that compared electromagnetic-guided placement with endoscopic-guided placement of feeding tubes through the nose. CORPAK MedSystems - a medical device company that specialises in tube feeding technology - funded two of the four studies, but it had no role in study design, data collection, data analysis, data interpretation, or writing of the study reports.

Main results

Compared with endoscopic-guided placement, electromagnetic-guided placement:

- may make little to no difference in the technical success of feeding tube placement;
- may make little to no difference in the proportion of participants with pneumonia;
- may make little to no difference in the time taken to place feeding tubes to reach the small intestine;
- probably reduces costs;
- may make little to no difference in the number of unwanted, harmful events.

What do the findings mean?

Due to a lack of robust evidence, it is unclear whether electromagnetic-guided placement at the bedside is superior to endoscopic-guided placement of feeding tubes in the small intestine. Future research in this area should focus on issues that are important to decision-makers. These include the question of which populations should be studied for electromagnetic-guided placement, and selecting key outcomes, including the details of unwanted effects and costs. 

What are the limitations of the evidence?

Our confidence in the results is limited because the results from the studies varied, and most studies involved only small numbers of people. Therefore, the results should be interpreted in light of these limitations.

How up to date is this evidence?

The evidence is current to February 2021.

Authors' conclusions: 

We found low-certainty evidence that electromagnetic-guided placement at the bedside results in little to no difference in technical success in insertion and aspiration pneumonitis, compared to endoscopic-guided placement. The heterogeneity of the healthcare professionals who performed the procedures and the small sample sizes limited our confidence in the evidence. Future research should be based on large studies with well-defined endpoints to potentially elucidate the differences between these two procedures.

Read the full abstract...
Background: 

For people who are malnourished and unable to consume food by mouth, nasoenteral feeding tubes are commonly used for the administration of liquid food and drugs. Postpyloric placement is when the tip of the feeding tube is placed beyond the pylorus, in the small intestine.  Endoscopic-guided placement of postpyloric feeding tubes is the most common approach. Usually, an endoscopist and two or more medical professionals perform this procedure using a guidewire technique. The position of the tube is then confirmed with fluoroscopy or radiography, which requires moving people undergoing the procedure to the radiology department. Alternatively, electromagnetic-guided placement of postpyloric nasoenteral feeding tubes can be performed by a single trained nurse, at the bedside and with less equipment than endoscopic-guided placement. Hence, electromagnetic-guided placement may represent a promising alternative to endoscopic-guided placement, especially in settings where endoscopy and radiographic facilities are unavailable or difficult to access.

Objectives: 

To assess the efficacy and safety of electromagnetic-guided placement of postpyloric nasoenteral feeding tubes compared to endoscopic-guided placement.

Search strategy: 

We searched the Cochrane Library, MEDLINE, Embase, CINAHL, ClinicalTrials.gov, World Health Organization International Clinical Trials Registry Platform, and OpenGrey until February 2021. We screened the reference lists of relevant review articles and current treatment guidelines for further literature. We contacted the study authors for missing data.

Selection criteria: 

We included randomised trials comparing electromagnetic-guided placement with endoscopic-guided placement of nasoenteral feeding tubes. We excluded prospective cohort studies, retrospective cohort studies, (nested) case‐control studies, cross‐sectional studies, and case series or case reports.

Data collection and analysis: 

Two review authors independently assessed the methodological quality of potentially eligible trials and extracted data from the included trials. The primary outcomes were technical success in insertion and aspiration pneumonitis. The secondary outcomes were the time for postpyloric placement of nasoenteral feeding tubes, direct healthcare costs, and adverse events. We performed a random‐effects meta-analysis. We calculated risk ratios (RRs) with 95% confidence intervals (CIs) for dichotomous outcomes and mean differences (MDs) with 95% CIs for continuous outcomes. We evaluated the certainty of evidence based on the GRADE approach.

Main results: 

We identified four randomised controlled trials with 541 participants which met our inclusion criteria. All trials had methodological limitations, and lack of blinding of participants and investigators was a major source of bias. We had 'some concerns' for the overall risk of bias in all trials. 

Electromagnetic-guided postpyloric placement of nasoenteral feeding tubes may result in little to no difference in technical success in insertion compared to endoscopic-guided placement (RR 1.09, 95% CI 0.88 to 1.35; I2 = 81%; low-certainty evidence). Electromagnetic-guided placement may result in a difference in the proportion of participants with aspiration pneumonitis compared to endoscopic-guided placement, but these results are unclear (RR 0.24, 95% CI 0.03 to 2.18; I2 = 0%; low-certainty evidence).  Electromagnetic-guided placement may result in little to no difference in the time for postpyloric placement of nasoenteral feeding tubes compared to endoscopic-guided placement (MD 4.06 minutes, 95% CI -0.47 to 8.59; I2 = 97%; low-certainty evidence). Electromagnetic-guided placement likely reduces direct healthcare costs compared to endoscopic-guided placement (MD -127.69 US dollars, 95% CI -135.71 to -119.67; moderate-certainty evidence). Electromagnetic-guided placement likely results in little to no difference in adverse events compared with endoscopic-guided placement (RR 0.78, 95% CI 0.41 to 1.49; moderate-certainty evidence).