CORTRAK Superuser Competency Assessment and Training Recommendations

Cortrak feeding tube safety: Criteria for interpreting lung misplacement

BACKGROUND

Pneumothorax occurs in 0.52% of blind tube placements, with 97% occurring in-procedure. Post-procedure pH or x-ray checks cannot prevent these, but CO2 checks or guided tube placement can. Cortrak guided tube placement is widespread, but manufacturer guidance to interpret lung placement is subjective.

AIM

Develop objective criteria to differentiate lung from oesophageal tube placement from measurements and patterns in Cortrak traces.

STUDY DESIGN

Paired comparison of lung and oesophageal Cortrak traces using a retrospective analysis of prospectively collected data in critically ill patients.

RESULTS

From 126 paired traces, lung position, versus oesophageal, was indicated by deviation from the sagittal midline further from the receiver and by a greater angle and distance. No lung trace moved deep to shallow and returned to the midline then turned left compared with 99.2% of oesophageal traces; 56.3% of traces had some degree of artefact caused by receiver misalignment and required interpretation to account for this.

CONCLUSIONS

Differences in trace measurements give early warning of lung placement, and absence of an oesophageal pattern is definitive. Manufacturer guidance describing Cortrak trace is subjective, lacking advice on how to interpret or correct for artefacts. This could fail to prompt a 'lung warning' and/or lead to unnecessary withdrawal of oesophageal placements; both risk trauma.

RELEVANCE TO CLINICAL PRACTICE

The objective criteria developed enable detection of lung placement. If regulatory authorities mandate their use in independently accredited training, Cortrak would be a safe method to confirm tube position.

Resident-Driven Guideline to Reduce Iatrogenic Pneumothoraxes From Small-Bore Feeding Tubes: A Quality and Safety Improvement Project

Small-bore feeding tubes (SBFT) in vulnerable patients carry a risk of iatrogenic pneumothorax by misplacement into the lung. This institution noted a series of iatrogenic pneumothoraxes caused by the placement of these devices. A resident-led, multidisciplinary team developed a hospital guideline through a consensus-driven process. The guideline mandated SBFT placement by approved "super-users" via the CORTRAK Enteral Access System or via non-CORTRAK Methods, including the 2-step X-ray Method, fluoroscopy, or direct visualization techniques. A "super-user" Program for the CORTRAK Enteral Access System was developed to assure competency and consistency. With the development of the guideline and "super-user" program, the authors observed a decrease in the number of SBFT-related iatrogenic pneumothoraxes. Following a brief period of adoption, the three-hospital organization has had no SBFT-related iatrogenic pneumothoraxes. This project demonstrates the effectiveness of developing a resident-driven, evidence-based hospital guideline for the safe passage of SBFTs.

Role of registered dietitians in nasoenteric feeding tube placement

Provision of enteral nutrition (EN) in hospitalized patients is an integral part of clinical care. For various reasons, including but not limited to delayed enteral access placement and EN initiation, it is becoming more prevalent for registered dietitians (RDs) to place feeding tubes in various clinical settings. Although numerous RDs have expanded their practice by learning this skill, many remain hesitant about adding feeding tube placement to their scope of responsibilities. Feeding tube placement is within RDs' scope of practice. The recently updated Accreditation Council for Education in Nutrition and Dietetics (ACEND) standards is requiring dietetic interns to learn the process and assist in placing feeding tubes. This will help promote the inclusion of this practice and open doors for future advancement in the scope of practice for RDs. This review will provide an overview of feeding tube placement methods, evidence-based techniques, training, competencies, and barriers to accepting this practice in dietetics.

Small-bore feeding tubes placed with an electromagnetic imaging device leads to cost avoidance and decreased time to initiation of enteral nutrition

BACKGROUND

The Cortrak Enteral Access System (CEAS) was previously approved by the United States Food and Drug Administration (FDA) to be used in lieu of radiographic confirmation imaging for feeding tubes placed by trained clinicians. Following an institutional protocol change in 2016, our registered dietitians had the option to forgo radiographic confirmation imaging for tubes placed using the CEAS. Our research aimed to determine the difference in the number of radiographic confirmation images for feeding tubes placed using the CEAS between preprotocol and postprotocol environments and the associated cost avoidance after the institutional policy change.

METHODS

We retrospectively reviewed data from 506 tube placements (n = 253 per protocol environment) in adult patients with diverse diagnoses admitted to various in-patient care units.

RESULTS

There was a significant reduction in the mean number of radiographic images per tube placement (preprotocol = 1.10 [95% CI, 1.05-1.15]; postprotocol = 0.36 [95% CI, 0.30-0.41]; P < 0.001), leading to a cost avoidance of $67,282.80 for the 253 tube placements and a potential cost avoidance of $279,236 over the 5-year postprotocol environment. Additionally, the mean time to initiation of enteral nutrition was significantly reduced by 2.65 h in the postprotocol environment (P < 0.001).

CONCLUSION

Our findings suggest that using the CEAS can reduce the number of radiographic images, provide cost avoidance, and improve nutrition outcomes. However, updated 2022 FDA regulatory changes to the use of the CEAS for tube confirmation lead to an uncertain future for this practice because of safety concerns.

Self-efficacy in the context of nursing education and transition to practice as a registered practitioner: A systematic review

AIM

The aim of this systematic review is to identify, describe and synthesize evidence from experimental studies conducted to measure and conceptualize self-efficacy within the context of nursing education and the transition of nursing students to practice as a registered practitioners.

DESIGN

Systematic review.

METHODS

Papers were screened by four independent reviewers, and data were extracted using a standardized data extraction tool. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidance and checklists were used to guide this review.

RESULTS

The review included 47 studies, using a quasi-experimental pre-test-post-test design (n = 39) and randomized control trials (n = 8). Various teaching and learning interventions were used to enhance self-efficacy; however, there is no definitive conclusion to be drawn regarding the most effective educational interventions. Various instruments were used in the studies to measure self-efficacy. 10 of these were related to general self-efficacy, while 37 instruments measured self-efficacy in the context of specific skills.

Safety of blind versus guided feeding tube placement: Misplacement and pneumothorax risk

Most intensive care unit patients require a feeding tube, but misplacement risk is high due to the presence of artificial airways and because unconsciousness reduces clinical warnings. Predominantly, tubes are placed 'blindly', where position is not known throughout placement. The result is that 1.6% enter the lung, 0.5% cause pneumothorax and potentially 5% are left in the oesophagus. Guided placement, by identifying tube position in real time, may prevent these problems, but undetected misplacements still occur. We review the safety of guided methods of confirming tube position, including rates of pneumothorax, in the context of current unguided methods. During blind tube placement, tube position can only be tracked intermittently. Excepting X-ray and ultra-sound, most methods of checking position are simple. Conversely, guided tube placement can track tube position from the nose to small intestine (IRIS®), or oesophagus to jejunum (Cortrak™, ENvue®). However, this requires expertise. Overall, guided placement is associated with lower rates of pneumothorax. Unfortunately, for Cortrak, low-use centres have higher rates of undetected misplacement compared with blind placement whereas Cortrak use in high-use centres had lower risk compared with blind placement and low use centres. Because guided placement requires high-level expertise manufacturer training packages have been developed but currently appear insufficient. Specifically, Cortrak's package is less accurate in determining tube position compared to the 'gastrointestinal flexure' system. Validation of an evidence-based guide for IRIS placement is underway. Recommendations are made regarding the training of new operators, including minimum numbers of placements required to achieve expertise.

Microbiome profile informs cleansing and storage practices for reusable feeding tube stylets in critical care

BACKGROUND

Cleansing and storage practices for reusable feeding tube stylets are varied and lack consensus guidelines. Almost 40% of critical care nurses do not cleanse reusable stylets. Our proof-of-concept study aimed to identify potential microbial contamination of stylets before and after cleansing with 70% isopropyl alcohol to establish practice standards.

METHODS

This prospective, exploratory pilot study sampled reusable feeding tube stylets using three different stylet sample sets. Set 1 included human participant stylets sampled for microbiome profile precleansing, and postcleansing and reinsertion into feeding tubes (n = 4). Sets 2 and 3 included stylets stored at the bedside. Set 2 included precleansed stylets for microbiome profiles (n = 5). Set 3 included precleansed and postcleansed stylets sampled for quantitative cultures (n = 5). Careful handling and storage protocols were used. Microbiome profiling used 16s ribosomal RNA gene amplicon sequencing.

RESULTS

Bacterial species identified on stylets were primarily common microflora and opportunistic pathogens, including Streptococcus pneumoniae, Staphylococcus aureus, Pseudomonas fulva, Cutibacterium acnes, Prevotella melaninogenica, and Lactobacillus paracasei. Microbiological culturing of stylet samples (set 3) did not yield growth for 9/10 samples; Staphylococcus capitis was identified in one postcleansed sample. Mean bacterial species diversity (alpha diversity) decreased following alcohol cleansing (M = 2.54 pre, M = 1.5 post; P = 0.006).

CONCLUSION

The abundance of several potentially opportunistic pathogens indicated plausible risk for gut contamination secondary to reinsertion of stylets into small-bore feeding tubes. Stylet cleansing with 70% isopropyl alcohol reduced bacterial burden on the stylets, although viability was unknown. Careful cleansing, handling, and storage protocols for reusable stylets are necessary to minimize contamination.

Intrapulmonary Feeding Tube Placements While Using an Electromagnetic Placement Device: A Review (2019-2021)

BACKGROUND

Intrapulmonary placements of feeding tubes inserted with use of an electromagnetic placement device (EMPD) continue to occur.

OBJECTIVE

To describe circumstances and outcomes associated with intrapulmonary feeding tube placements during use of an EMPD.

METHODS

A retrospective review of reports to the US Food and Drug Administration's Manufacturer and User Facility Device Experience (MAUDE) database of intrapulmonary feeding tube placements during use of an EMPD from 2019 through 2021. Complications, outcomes, operator training, interference from anatomical variations and medical devices, and the use and accuracy of radiographs in identifying pulmonary placements were recorded.

RESULTS

Sixty-two cases of intrapulmonary tube placement were identified; 10 were associated with a fatal outcome. Pneumothorax occurred in 35 cases and feedings were delivered into the lung in 11 cases. User error was cited in 6 cases and was implicit in most others. Little information was provided about operator training. Four intrapulmonary placements were associated with anatomical variations and 1 with a left ventricular assist device. Radiographic follow-up was described in 28 cases and correctly identified 23 of the intrapulmonary placements.

CONCLUSIONS

User error was a significant factor, which highlights the need for empirical data to clarify the amount of training needed to safely credential EMPD operators. Clearer information is needed about anatomical variations that may contraindicate use of an EMPD, as well as medical devices that may interfere with an EMPD. Use of follow-up radiographs, interpreted by qualified personnel, is supported to increase the probability of identifying intrapulmonary tube placements.

Using an Electromagnetic Guidance System for Placement of Small-Bowel Feeding Tubes to Reduce Feeding Start Times

BACKGROUND

Cardiothoracic surgery patients have an increased risk for aspiration and may require enteral access for nutrition.

LOCAL PROBLEM

In a cardiothoracic intensive care unit, feeding start times were delayed because of scheduling conflicts with support services. An electromagnetic device (Cortrak 2 Enteral Access System, Avanos Medical) was introduced to allow advanced practice providers (nurse practitioners and physician assistants) to independently establish postpyloric access and reduce dependence on ancillary services.

METHODS

A quality improvement study was performed. Pre- and postimplementation data included order time, service arrival, tube placement time, tube positioning, and feeding start times for 207 placements. Pre- and postimplementation surveys were conducted to evaluate advanced practice provider satisfaction with enteral tube placement practices.

RESULTS

Feeding start time for initial placement decreased by 35.5% (15.6 hours to 10 hours); for subsequent placement, by 55.2% (15.5 hours to 7.0 hours). Assistance by support services decreased by 80.4% (before implementation, 100 of 100 placements [100%]; after implementation, 21 of 107 placements [19.6%]; P < .001; ϕ = 0.815). Overall, advanced practice provider satisfaction increased. Most participants said that using the electromagnetic device was faster, nutrition was delivered sooner, and implementation was a valuable practice change.

CONCLUSIONS

Using an electromagnetic device decreased feeding start times, reduced the need for support services, and increased advanced practice provider satisfaction with small-bowel feeding tube placement practices.

Electromagnetic-guided versus endoscopic-guided postpyloric placement of nasoenteral feeding tubes

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 METHODS

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).

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.

The feasibility of electromagnetic sensing aided post pyloric feeding tube placement (CORTRAK) in patients with thrombocytopenia with or without anticoagulation on the intensive care unit

BACKGROUND

The successful initiation of enteral nutrition is frequently hampered by various complications occurring in patients treated in the intensive care unit (ICU). Successful placement of a nasojejunal tube by CORTRAK enteral access system (CEAS) has been reported to be a simple bedside tool for placing the postpyloric (PP) feeding tube.

METHODS

We evaluated the efficacy and side effects using CEAS to establish EN in patients with critical illness, thrombocytopenia, and/or anticoagulation.

RESULTS

Fifty-six mechanically ventilated patients were analyzed. Twenty-four of them underwent prior hematopoietic stem cell transplantation (SCT). Sixteen patients received extracorporeal membrane oxygenation treatment because of acute respiratory distress syndrome. The median platelet count at PP placement was 26 g/L (range, 4-106 g/L); 16 patients received therapeutic anticoagulation (activated partial thromboplastin time, 50-70 s). CEAS-assisted placement of a PP nasojejunal tube was performed successfully in all patients. The most frequent adverse event was epistaxis in 27 patients (48.2%), which was mostly mild (Common Terminology Criteria for Adverse Events grade 1, n = 21 [77.8%], and grade 2, n = 6). A significant association between a low platelet count and bleeding complications was observed (P < 0.001).

CONCLUSION

Performed by an experienced operator, CEAS is a simple, rapidly available, and effective bedside tool for safely placing PP feeding tubes for EN in patients with thrombocytopenia, even when showing an otherwise-caused coagulopathy in the ICU. Higher-grade bleeding complications were not observed despite their obvious correlation to thrombocytopenia. A prospective study is in preparation.

Comparison of electromagnetic guided imagery to standard confirmatory methods for ascertaining nasogastric tube placement in children

PURPOSE

Evaluate the accuracy of an electromagnetic device (EMD) guided nasogastric tube (NGT) placement compared with standard confirmation methods. A secondary aim was to determine if EMD guided NGT placement would avert potential pulmonary misplacements of the tube.

DESIGN AND METHODS

Pediatric Intensive Care Unit (PICU) patients were enrolled if they had an NGT order during the study period of April 2014 through December 2016. Patients were included if they were one through 18 years of age. An EMD trained nurse inserted the NGT using EMD guidance. An insertion questionnaire, confirming if the nurse determined the NGT to be gastric per EMD, was completed immediately after NGT placement and before confirmation via either pH testing or radiographic imaging.

RESULTS

Forty-five patients were enrolled in the study. Nurses reported, based on EMD, that 86.7% (n = 39) of placements were gastric. Overall agreement between EMD guided tube placement and pH testing was 58% (n = 26). The marginal distribution was significantly different between the two methods (p = .0029). When compared to radiographic confirmation, sensitivity of the pH method was 32% (95% confidence interval [CI]: 17%-51%) compared with 85% (95% CI 69%-95%) for the EMD method.

CONCLUSIONS

EMD guidance was superior to pH testing when compared with radiographic confirmation of nasogastric tube placement in children.

PRACTICE IMPLICATIONS

EMD guided NGT placement is a potentially viable method for confirming nasogastric tube placement in children when done by appropriately trained clinicians. More research on EMD guided NGT placement in children is needed before any practice recommendation can be made.

Nasogastric Tube Placement: A Cross-Comparison of Verification Methods Used in Pennsylvania Hospitals and How They Align With Guidelines

Nasogastric tubes (NGTs) are used as an alternative approach to deliver nutrition and medications, or a method to remove stomach contents. Insertion of these tubes is considered a simple procedure; however, wrong placement or dislodged tubes can lead to patient harm and possibly death. The risk of harm and death increases when misplaced or dislodged tubes are not identified prior to using them. We queried the Pennsylvania Patient Safety Reporting System for events that occurred between January 1, 2017, and June 30, 2020. We analyzed those reports that provided supplemental information describing NGT placement verification methods to determine how these activities aligned with NGT guidelines. The use of X-rays and pH aspirate, guideline-approved verification methods, were identified in 90.8% (544 of 599) of the reports. In 9.2% (55 of 599) of the reports, the use of non-recommended verification methods (e.g., insertion of air bolus/auscultation, were identified). Reports indicated that patients aged less than one year old experienced a higher percentage of non-recommended verification methods being used when compared to all other patients. Interviews with staff at three healthcare facilities discussed their approach to verifying NGT placement. Risk reduction strategies comprise using the guideline recommendations to verify NGT placement and avoiding the use of non-recommended verification methods.

Development of a Competency Model for Placement and Verification of Nasogastric and Nasoenteric Feeding Tubes for Adult Hospitalized Patients

Nasogastric/nasoenteric (NG/NE) feeding tube placements are associated with adverse events and, without proper training, can lead to devastating and significant patient harm related to misplacement. Safe feeding tube placement practices and verification are critical. There are many procedures and techniques for placement and verification; this paper provides an overview and update of techniques to guide practitioners in making clinical decisions. Regardless of placement technique and verification practices employed, it is essential that training and competency are maintained and documented for all clinicians placing NG/NE feeding tubes. This paper has been approved by the American Society for Parenteral and Enteral Nutrition (ASPEN) Board of Directors.

Cortrak feeding tube placement: interpretation agreement of the ‘GI flexure’ system versus X-ray

Background:

Blind (unguided) feeding tube placement results in 0.5% of patients suffering major complications mainly due to lung misplacement detected prior to feeding. Electromagnet-guided (Cortrak) tube placement could pre-empt such complications but undetected misplacements still occur due to incorrect trace interpretation. By identifying gastrointestinal (GI) flexures from the trace, ‘the GI flexure system’, it has been proposed that tube position can be interpreted.

Aims:

To audit agreement between standards of interpreting tube position: the Cortrak ‘GI flexure’ system versus X-ray.

Methods:

In 185 primary nasointestinal tube placements tube position determined by Cortrak trace interpretation (GI flexure) was retrospectively compared with radiological position in a blinded study.

Findings:

Radiological and Cortrak interpretation agreed in 92.2–98.3% of placements at different GI flexures. Discrepancy mainly occurred because some radiological images were unclear or did not cover all anatomical points.

Conclusion:

The GI flexure method of Cortrak interpretation appears safe but would necessitate prospective radiological investigation to definitively test equivalence.

Pneumothoraces Prevented With Use of Electromagnetic Device to Place Feeding Tubes

BACKGROUND

A US Food and Drug Administration safety letter warned about the risk for pneumothoraces during feeding tube insertion despite the use of electromagnetic placement devices that provide real-time visualization of feeding tube position.

OBJECTIVES

To systematically assess pulmonary placement and pneumothoraces in CORTRAK-assisted feeding tube insertions.

METHODS

CINAHL, MEDLINE, and Cochrane databases were searched for studies of CORTRAK-assisted feeding tube insertion. Thirty-two studies documenting pulmonary placement and/or complications of feeding tube insertion were found.

RESULTS

Operators recognized pulmonary placement on insertion tracings during 202 CORTRAK-assisted feeding tube insertion procedures, resulting in the immediate withdrawal of 199 feeding tubes. One pneumothorax was identified later by radiography. Seven pulmonary placements were not recognized by CORTRAK operators at the time of feeding tube insertion, resulting in 2 pneumothoraces. The incidence of pneumothorax for CORTRAK-assisted feeding tube insertions was 0.02% (3 of 17039). Of the feeding tubes inserted into the pulmonary system - either found during or after the procedure -1.4% (3 of 209) resulted in pneumothoraces (as opposed to the 19% to 28% incidence of pneumothorax for blind feeding tube insertions. Operators recognizing pulmonary placement on CORTRAK insertion tracings may have prevented 97% (202 of 209) of feeding tubes from being inserted farther into the respiratory tract.

CONCLUSIONS

Feeding tube insertion with an electromagnetic placement device is advantageous over blind feeding tube insertion because the operator can recognize pulmonary placement early and withdraw the feeding tube, thus decreasing the risk of pulmonary complications.

Undetected Cortrak tube misplacements in the United Kingdom 2010-17: An audit of trace interpretation

OBJECTIVES

Determine why Cortrak-guided, undetected tube misplacement may occur in relation to the system of trace interpretation used.

METHODOLOGY

From 2010 to 2017 we obtained seven of the eight Cortrak traces from the United Kingdom where misplacement was undetected and the patient received feed. Seven suffered serious harm. Each misplacement was interpreted by three systems: screen position, manufacturer guidance and gastrointestinal (GI) flexures.

SETTING

National and local records.

MAIN OUTCOME MEASURES

Ability to identify misplacement.

RESULTS

Traces that were later identified as misplacements, could not be differentiated from GI position when they wholly or partially: a) overlapped with the GI screen area plotted from historical records (57-71%) or b) met both manufacturer guidance criteria or were confused with receiver misplacement or unusual anatomy and reached the lower left quadrant (14-71%). Conversely, all lung misplacements were identified as unsafe using the GI flexure system. All three systems failed to detect the intra-peritoneal trace. Traces were inconsistently stored by healthcare centres.

CONCLUSION

Trace file storage should be mandated by and accessible to relevant health authorisation bodies to improve safety research. Screen position alone and manufacturer guidance fail to consistently differentiate the shape of safe from unsafe traces. GI flexure interpretation appears safer but requires testing in larger studies.