Accuracy of pH strip testing and pH liquid testing versus standard pH meter of gastric contents in critically ill patients: a diagnostic accuracy study

OBJECTIVE

The utilisation of pH level measurements from gastric contents may indicate the preferred tip position of a nasogastric tube or monitor the efficacy of stress ulcer prophylaxis in critically ill patients. We aimed to determine the accuracy of pH strip (pHS) tests and pH liquid (pHL) tests compared with the standard pH meter (pHM).

DESIGN

Diagnostic accuracy study.

SETTING

Gastric contents from medically critically ill patients.

PARTICIPANTS

In total, 113 gastric samples were collected from 27 critically ill patients.

OUTCOME MEASURE

The level of pH measured by pHM, pHS and pHL.

RESULTS

The pH values measured by pHM, pHS and pHL were 5.83 (IQR 5.12-6.61), 5.50 (IQR 5.00-6.00) and 5.75 (IQR 5.25-6.25), respectively. The pHS test showed greater accuracy, exhibiting a more positive correlation with the standard pHM measurement than the pHL test, with Y=0.95*X+0.56; rho=0.91, p<0.001, and Y=1.09*X - 0.72; rho=0.75, p<0.001, respectively. However, the pHS test demonstrated less agreement with the pHM than the pHL test, with biases of -0.27 versus 0.18, respectively. Noticeably, a slight variation in pHL from the standard pH values was found when we measured gastric contents with a pH lower than 5.

CONCLUSION

Both the pHS and pHL methods were good options for measuring gastric pH in critically ill patients. However, it was advisable to find alternative approaches to the pHL testing method when anticipated gastric acidity levels fall below 5.

TRIAL REGISTRATION NUMBER

TCTR20220530004.

Validating nasogastric tube placement with pH testing: A randomized controlled trial protocol

Background

Enteral nutrition (EN) is preferred when oral feeding is not possible. The use of the Nasogastric Tube (NGT) ensures rapid and low-risk nutrient administration. However, confirming the placement through chest radiography, besides delaying the initiation of nutritional therapy, exposes patients to radiation. The pH test of gastric aspirate provides a quicker check for NGT placement, but its reliability is compromised by challenges related to aspirating gastric secretions.

Study objective

The main objective of this study is to assess the high-performance placement of NGTs for nutritional purposes, optimizing the evaluation of correct insertion through pH testing using an electronic pH meter. Additionally, the study aims to evaluate patient tolerance to the intervention.

Materials and methods

This single-center RCT will include 150 EN candidate patients divided into three groups. Each group will use distinct NGTs, evaluating placement through pH testing and chest radiography for safety. Tolerance, complications related to NGT placement, and costs will be assessed, with data collected anonymously through a secure electronic database.

Ethical considerations

authorization no. 3624, Territorial Ethical Committee Lombardy 5, October 20, 2023.

Implications and perspectives

This protocol introduces innovative technologies, such as advanced NGTs and an electronic pH meter, aiming to optimize enteral nutrition management. This RCT focuses on replacing X-rays as the primary method for verifying NGT placement, thereby reducing costs, time, and patient exposure to radiation. Data analysis may provide insights into managing patients on pH-altering medication. Implementing innovative technologies has the potential to reduce errors and improve economic efficiency and process sustainability.

Nasogastric tube insertion length measurement and tip verification in adults: a narrative review

Nasogastric feeding tube insertion is a common but invasive procedure most often blindly placed by nurses in acute and chronic care settings. Although usually not harmful, serious and fatal complications with misplacement still occur and variation in practice still exists. These tubes can be used for drainage or administration of fluids, drugs and/or enteral feeding. During blind insertion, it is important to achieve correct tip position of the tube ideally reaching the body of the stomach. If the insertion length is too short, the tip and/or distal side-openings at the end of the tube can be located in the esophagus increasing the risk of aspiration (pneumonia). Conversely, when the insertion length is too long, the tube might kink in the stomach, curl upwards into the esophagus or enter the duodenum. Studies have demonstrated that the most frequently used technique to determine insertion length (the nose-earlobe-xiphoid method) is too short a distance; new safer methods should be used and further more robust evidence is needed. After blind placement, verifying correct gastric tip positioning is of major importance to avoid serious and sometimes lethal complications.

Comparison of 3 Methods for Measuring Gastric Tube Length in Newborns: A Randomized Clinical Trial

BACKGROUND

Incorrectly positioned gastric tubes occur in approximately 60% of infants hospitalized in the neonatal intensive care unit (NICU), increasing the risk of potentially serious complications.

PURPOSE

To compare 3 methods of determining gastric tube insertion length in infants in the NICU.

METHODS

In this randomized triple-blind clinical trial, 179 infants admitted to the NICU were randomized to have their gastric tube insertion length determined by 1 of 3 methods: (1) the nose, earlobe, mid-umbilicus (NEMU) method, (2) a weight-based method, or (3) an age-related height-based (ARHB) method. Positioning of the gastric tube was verified by radiograph. R software was used for analyses. To compare categorical variables, Fisher's exact test, χ2 tests, and simulated χ2 tests were used.

RESULTS

Overall, infants had a mean gestational age of 35 weeks, 115 (58.8%) were male, and the mean birth weight was 2481.5 g. Upon radiological assessment, 145 gastric tubes (81.3%) were correctly positioned in the gastric body or greater curvature of the stomach with the weight-based method having the highest percentage of correctly positioned gastric tubes (n = 53; 36.6%), followed by the ARHB method (n = 47; 32.4%) and the NEMU method (n = 45; 31.0%). No significant differences were identified between groups (P = .128).

IMPLICATION FOR PRACTICE AND RESEARCH

Despite the NEMU method being the most commonly used method in clinical practice, the weight-based and ARHB methods to determine gastric tube insertion length may be more accurate.

[Safe position check of gastric tubes: an often underestimated topic to prevent possible severe complications]

The insertion of a gastric tube in the operating room (OR) or in an intensive care unit (ICU) is a routine procedure. Although the tube is often inserted by nursing staff, the indications and selection of the procedure for position control remain the physician's responsibility. For immediate position control, the injection of air through the inserted tube with simultaneous auscultation of the epigastrium is probably the most simple and common clinical method. A typical "bubbling" is often regarded as a sufficiently reliable sign of correct gastric tube position. This procedure can be described as a routine standard both in the OR and the ICU; however, numerous examples from clinical practice and quality reviews show gastric tube mispositioning in esophageal, bronchial, pulmonary or even pleural positions in individual cases. Since auscultation findings are misinterpreted as tracheal, bronchial, or pleural secretions, mispositioning may remain undetected. In addition, adequate documentation of the procedure is lacking. In the worst case, hyperosmolar tube feeding occurs via the malpositioned tube into the lungs or pleural space causing subsequent severe pneumonia or pleuritis, which is often fatal for the patient outcome. In contrast to many other similar procedures in intensive care medicine, such as the installation of central venous catheters or endotracheal intubation, to our knowledge there is no uniform standard for forensic verification of the correct position after gastric tube positioning. The present work provides an overview of existing practices and the scientific background for confirmation of gastric tube positioning without ionizing radiation.

Randomized Trial to Compare Nasoduodenal Tube and Nasogastric Tube Feeding in Infants with Bronchiolitis on High-Flow Nasal Cannula

Objectives In this article, we aimed to determine if there is a difference in length of respiratory support between nasoduodenal (NDT) and nasogastric tube (NGT) feedings in patients with bronchiolitis on high-flow nasal cannula (HFNC).

Methods A single-center nonblinded parallel randomized control trial at a tertiary care hospital was designed. Pediatric patients ≤ 12 months old with bronchiolitis, on HFNC, requiring nutrition via a feeding tube were eligible. Patients were randomized to NGT or NDT and stratified into low- and high-risk groups. Length of respiratory support was the primary outcome. Secondary outcomes included length of stay, number of emesis events, maximum level of respiratory support, number of X-rays to confirm tube placement, number of attempts to place the tube by staff, adverse events during placement, instances of pediatric intensive care unit admission, and emergency room visits and hospital readmissions within 7 and 30 days after discharge.

Results Forty patients were randomized, 20 in each arm. There were no significant differences in baseline characteristics. We found no significant difference in length of respiratory support between the two groups (NGT 0.84 incidence rate ratio [0.58, 1.2], p = 0.34). None of the secondary outcomes showed significant differences. Each arm reported one adverse event: nasal trauma in the NGT group and pneumothorax in the NDT group.

Conclusion For infants with bronchiolitis on HFNC that need enteric tube feedings, we find no difference in duration of respiratory support or other clinically relevant outcomes for those with NGT or NDT. These results should be interpreted in the context of a limited sample size and an indirect primary outcome of length of respiratory support that may be influenced by other factors besides aspiration events.

Nasogastric tube in mechanical ventilated patients: ETCO2 and pH measuring to confirm correct placement. A pilot study

INTRODUCTION

Nasogastric tube (NGT) placement is a procedure commonly performed in mechanically ventilated (MV) patients. Chest X-Ray is the diagnostic gold-standard to confirm its correct placement, with the downsides of requiring MV patients' mobilization and of intrinsic actinic risk. Other potential methods to confirm NGT placement have shown lower accuracy compared to chest X-ray; end-tidal CO2 (ETCO2) and pH analysis have already been singularly investigated as an alternative to the gold standard. Aim of this study was to determine threshold values in ETCO2 and pH measurement at which correct NGT positioning can be confirmed with the highest accuracy.

MATERIALS & METHODS

This was a prospective, multicenter, observational trial; a continuous cohort of eligible patients was allocated with site into two arms. Patients underwent general anesthesia, orotracheal intubation and MV; in the first and second group we respectively assessed the difference between tracheal and esophageal ETCO2 and between esophageal and gastric pH values.

RESULTS

From November 2020 to March 2021, 85 consecutive patients were enrolled: 40 in the ETCO2 group and 45 in the pH group. The ETCO2 ROC analysis for predicting NGT tracheal misplacement demonstrated an optimal ETCO2 cutoff value of 25.5 mmHg, with both sensitivity and specificity reaching 1.0 (AUC 1.0, p < 0.001). The pH ROC analysis for predicting NGT correct gastric placement resulted in an optimal pH cutoff value of 4.25, with mild diagnostic accuracy (AUC 0.79, p < 0.001).

DISCUSSION

In patients receiving MV, ETCO2 and pH measurements respectively identified incorrect and correct NGT placement, allowing the identification of threshold values potentially able to improve correct NGT positioning.

TRIAL REGISTRATION

NCT03934515 (www.clinicaltrials.gov).

Point-of-Care Ultrasound for Confirmation of Nasogastric and Orogastric Tube Placement in Pediatric Patients

OBJECTIVES

The aim of the study was to investigate the role of point-of-care ultrasound (POCUS) as an alternative imaging modality to confirm proper placement for nasogastric tubes (NGTs) and orogastric tubes (OGTs) in pediatric patients.

METHODS

This was a prospective descriptive study performed at a tertiary care free-standing children's hospital. Patients 21 years and younger requiring radiographic confirmation of NGT or OGT placement were eligible for enrollment. Bedside ultrasonography examination of the epigastric area was performed by a blinded pediatric emergency medicine physician. An abdominal radiograph was obtained to confirm NGT or OGT placement in all patients.

RESULTS

A total of 26 patients with a mean age of 2.6 years (standard deviation, 3.9 years) were enrolled. All 26 patients had x-ray confirmation of NGT and OGTs correctly placed in the stomach. Confirmation of NGT or OGT placement by ultrasound was obtained in 23 patients. For these 23 patients, POCUS agreed with radiographic findings. For 3 patients, the NGT and OGT was unable to be identified by ultrasound. The sensitivity of ultrasound for detecting a properly placed tube was 88% (95% confidence interval, 70.0%-97.6%).

CONCLUSIONS

This pilot study described ultrasound confirmation of NGT or OGT placement. If confirmed in larger studies, POCUS can be used as an objective tool for the confirmation of NGT or OGT placement in pediatric patients and limit the need for routine x-ray confirmation.

Reining in Nasogastric Tubes: Implementation of a Pediatric Bridle Program

Nasogastric tubes (NG) used for enteral nutrition support of medically complex children (MCC) are often inadvertently removed, risking frequent replacements. Bridles have been shown to provide a safe securement method for NGs in adult patients, but are not widely used in pediatrics. Furthermore, nutritional management of MCC is often fragmented. We established a pediatric NG bridle program to bridge the gap amongst disciplines and improve patient outcomes. In January 2018, a multidisciplinary work group involving nurses, physicians, clinical dietitians, advanced practice providers, and speech-language pathologists was established to develop criteria for patient referral and policies, procedures, and order sets for nutritional management of MCC children with bridled NG tubes. Formal teaching sessions engaged clinicians and administrators to participate in building a successful program. Relevant outcomes of interest are tracked continuously for process performance improvement measures and are reviewed quarterly by the core work group. Patient enrollment began in May 2018 and to date, 244 patients have been enrolled. Adhering to strict enrollment criteria, competency modules and review of patient status provided a solid core for the program and process review. Successful implementation of an NG Bridle program was achieved. Outcomes of interest continue to be monitored for process improvement. Balancing measures are also being tracked for potential downstream effects.

Ongoing pH testing to confirm nasogastric tube position before feeding to reduce the risk of adverse outcomes in adult and paediatric patients: A systematic literature review

BACKGROUND & AIMS

There is no agreed gold standard method to confirm nasogastric tube position before every use. However, many global guidelines recommend testing the pH of gastric aspirates obtained from an NGT before each use. This study aims to determine whether ongoing pH testing has been shown to reduce adverse events. Secondary aims are to determine how frequently aspirates can be obtained, and how often pH correctly confirms ongoing NGT tip position.

METHODS

Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed and protocol was published on PROSPERO. Keywords were used to search PubMed, Embase, CENTRAL, CINAHL and MEDLINE. Article assessment for inclusion was completed by two independent authors and risk of bias was assessed using ROBINS-I.

RESULTS

The systematic search and review methodology was followed due to wide variety and high risk of bias in the included studies. One full study and five abstracts met inclusion criteria for the primary aim. The full article contained one instance where pH testing and external NGT length together identified a misplaced NGT. The abstracts identified missed or delayed feeds and medications, and frequent unnecessary X-rays, as negative outcomes of ongoing pH testing. Ten full studies and one conference abstract addressed the secondary aims, but the studies varied widely which prevented meta-analysis and made it difficult to draw conclusions.

CONCLUSIONS

This review confirmed that ongoing pH testing is based on expert opinion due to limited evidence. More primary research is required to determine the clinical impact of ongoing pH testing to confirm NGT position.

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.

A Cross-sectional Survey of Enteral Feeding Tube Placement and Gastric Residual Aspiration Practices: Need for an Evidence-Based Clinical Practice Guideline

BACKGROUND

Preterm infants routinely require enteral feeding via nasogastric or orogastric tubes as an alternative to oral feeding to meet their nutritional needs. Anecdotal evidence suggests variations in practice related to correct tube placement and assessment of feed intolerance.

PURPOSE

To determine the current practices of enteral feeding tube placement confirmation and gastric residual (GR) aspiration of neonatal clinicians in Australia.

METHODS

A cross-sectional online survey comprising 24 questions was distributed to nursing and medical health professionals working in Australian neonatal care units through 2 e-mail listservs made available by professional organizations.

FINDINGS

The survey was completed by 129 clinicians. A single method was practiced by 50% of the clinicians in confirming tube placement, and most common practice was assessing the pH of GR aspirate. The majority of respondents (96%) reported that they relied on GR aspiration and clinical signs to determine feeding tolerance and subsequent decisions such as ceasing or decreasing feeds. However, the frequency of aspiration, the amount and color of aspirate considered to be normal/abnormal, and decisions on whether to replace gastric aspirate or whether aspiration should be performed during continuous tube feeding varied.

IMPLICATION FOR PRACTICE

This study demonstrated considerable variability in clinical practice for enteral feeding tube placement confirmation and GR aspiration despite most respondents reporting using a unit-based clinical practice guideline. Our study findings highlight the need for not only developing evidence-based practice guidelines for safe and consistent clinical practice but also ensuring that these guidelines are followed by all clinicians.

IMPLICATION FOR RESEARCH

Further research is needed to establish evidence-based methods both for enteral feeding tube placement confirmation and for the assessment of feeding intolerance during tube feeding. In addition, the reasons why evidence-based methods are not followed must be investigated.

Nutritional Support in the Intensive Care Unit: Implications for Nursing Care From Evidence-Based Guidelines and Supporting Literature

Several nursing practices are related to oral, enteral, or parenteral feeding on the intensive care unit. Nurses are the group of health care professionals who provide 24-hour care for patients. Therefore, they play a key role in not only identifying nutritional problems but also in ensuring the success of nutritional therapy by implementing evidence-based feeding protocols and ongoing care for (par)enteral access devices. Having an up-to-date evidence-based knowledge about nutritional support can increase safety and quality of care and can contribute to better outcomes. In this narrative review, the most recent European intensive care unit nutrition guidelines and related research are highlighted, and where appropriate, specific applications for nursing practice are described.

Misplacement of a nasogastric feeding tube: a case report

Nasogastric tube (NGT) insertion is widely used for enteral feeding. After blind insertion of a NGT, confirmation of correct placement prior to feeding using reliable methods is mandatory. NGT misplacement in the respiratory tract can lead to serious complications. We report a case of a patient with dysphagia and malnutrition that needed enteral feeding as nutritional support. A NGT was blindly inserted, and its gastric position was confirmed through air insufflation and epigastric auscultation. Enteral feeding was initiated. Few hours later, the patient presented with respiratory distress. An urgent thoracic computed tomography was requested due to suspiction of pulmonary embolism, which revealed the NGT in the respiratory tree and a pneumonia in the lower lobe of the right lung. The NGT was removed, a new insertion was attempted and its gastric position was confirmed by radiography. Enteral feeding was initiated uneventfully. This case highlights the need for use of reliable methods of confirming tube location in order to avoid complications of misplacement.

Acidity of Enteral Feeding Tube Aspirate in Neonates: Do pH Values Meet the Cutoff for Predicting Gastric Placement?

BACKGROUND

Enteral feeding tubes (EFTs) are commonly used in neonatal practice, but complications from tube misplacement remain a concern. Measuring the pH of EFT aspirate is a recommended method to evaluate EFT placement. A pH value of ≤5.5 is considered predictive of gastric placement. Using this method in infants has been questioned. It is unclear whether infants can produce adequate gastric acid to achieve a pH 5 or less and whether feedings and medications influence pH.

PURPOSE

To report EFT aspirate pH values in infants and to evaluate factors potentially influencing pH values.

METHODS

A retrospective descriptive study was conducted with 1024 infants with 6979 pH values. Demographic and clinical data were collected including type of EFT, pH of gastric aspirate, feeding method, time of last feeding, and administration of acid suppression medications. The frequency of measured pH values of 5 or less was calculated for each covariate.

FINDINGS/RESULTS

The majority (97.51%) of pH values were 5 or less. Orogastric tubes, continuous feeding, a 4-hour or more feeding interval, exposure to medications (proton pump inhibitor, histamine-2 receptor antagonist, or multiple medications) were associated with an increased likelihood of pH values of more than 5. However, with each study variable the majority of pH values were 5 or less.

IMPLICATIONS FOR PRACTICE

These findings suggest EFT pH, a recommended method to evaluate the likelihood of gastric placement, can be successfully used in the neonatal population.

IMPLICATIONS FOR RESEARCH

Future research should prospectively evaluate EFT pH in infants when compared with clinically indicated radiographs. Other factors that might influence pH should be explored including severity of illness, feeding type, and other medications.

Use of pH reagent strips to verify gastric tube placement in newborns

Objective:

to confirm the accuracy of the pH test in identifying the placement of the gastric tube in newborns.

Method:

double-blind, diagnostic test study conducted with 162 newborns admitted to a neonatal intensive care unit and an intermediate care unit. The subjects were submitted to enteral intubation, followed by pH test with reagent strip, which was analyzed by a nurse, and radiological examination, analyzed by radiologist. Blinding was kept among professionals regarding test results. Diagnostic accuracy analysis of the pH test in relation to the radiological exam was performed.

Results:

the sample consisted of 56.17% boys, with average birth weight of 1,886.79g (SD 743,41), 32.92 (SD 2.99) weeks of gestational age and the mean pH was 3.36 (SD 1.27). Considering the cutoff point of pH≤5.5, the sensitivity was 96.25%, specificity 50%, positive predictive value 99.35% and negative predictive value 14.29%.

Conclusion:

The pH test performed with reagent strips is sensitive to identify the correct placement of the gastric tube, so it can be used as an adjuvant technique in the evaluation of the gastric tube placement. In interpreting the results, pH ≤5.5 points to correct placement and values > 5.5 require radiological confirmation.

Pediatric Nasogastric Tubes in the Home: Recommendations for Practice

One of the dilemmas facing home healthcare nurses is the placement of a nasogastric tube (NGT) in the home setting coupled with being assured and confident that the NGT tip is in the correct position, that is, the stomach. There are very limited data to address the issue of management of an NGT in the home care setting with even less guidance for the pediatric population. Therefore, home healthcare nurses must use agency policy and procedures coupled with their own education, knowledge, experience, and skills when performing this procedure. These may vary from agency to agency, thus providing inconsistencies in teaching and techniques.

Pediatric Nasogastric Tube Placement and Verification: Best Practice Recommendations From the NOVEL Project

The placement of a nasogastric tube (NGT) in a pediatric patient is a common practice that is generally perceived as a benign bedside procedure. There is potential risk for NGT misplacement with each insertion. A misplaced NGT compromises patient safety, increasing the risk for serious and even fatal complications. There is no standardized method for verification of the initial NGT placement or reverification assessment of NGT location prior to use. Measurement of the acidity or pH of the gastric aspirate is the most frequently used evidence-based method to verify NGT placement. The radiograph, when properly obtained and interpreted, is considered the gold standard to verify NGT location. However, the uncertainty regarding cumulative radiation exposure related to radiographs in pediatric patients is a concern. To minimize risk and improve patient safety, there is a need to identify best practice and to standardize care for initial and ongoing NGT location verification. This article provides consensus recommendations for best practice related to NGT location verification in pediatric patients. These consensus recommendations are not intended as absolute policy statements; instead, they are intended to supplement but not replace professional training and judgment. These consensus recommendations have been approved by the American Society for Parental and Enteral Nutrition (ASPEN) Board of Directors.

Enteral Access Devices: Types, Function, Care, and Challenges

Enteral access feeding devices are placed in patients who have a functional and accessible gastrointestinal (GI) tract but are not able to consume or absorb enough nutrients to sustain adequate nutrition and hydration. For many individuals, enteral nutrition support is a lifesaving modality to prevent or treat a depleted nutrient state that can lead to tissue breakdown, compromised immune function, and poor wound healing. Psychological well-being is also affected with malnutrition and dehydration, triggering feelings of apathy, depression, fatigue, and loss of morale, negatively impacting a patient's ability for self-care. A variety of existing devices can be placed through the nares, mouth, stomach or small intestine to provide liquid nutrition, fluids, and medications directly to the GI tract. If indicated, some of the larger-bore devices may be used for gastric decompression and drainage. These enteral access devices need to be cared for properly to avert patient discomfort, mechanical device-related complications, and interruptions in the delivery of needed nutrients, hydration, and medications. Clinicians who seek knowledge about enteral access devices and actively participate in the selection and care of these devices will be an invaluable resource to any healthcare team. This article will review the types, care, proper positioning, and replacement schedules of the various enteral access devices, along with the prevention and troubleshooting of potential problems.

Comparison of Neonatal Nursing Practices for Determining Feeding Tube Insertion Length and Verifying Gastric Placement With Current Best Evidence

BACKGROUND

Oral-nasogastric feeding tubes (FTs) are often malpositioned, placing infants at risk for complications. Confusion exists regarding the accuracy of methods to determine FT insertion length and verify gastric FT placement, and it is unknown whether evidence-based methods are used by neonatal nurses.

PURPOSE

To compare individual and unit-based neonatal nursing practices regarding methods used to determine FT insertion length and verify gastric FT placement.

METHODS

Neonatal nurses were surveyed about individual and unit-based practices regarding methods used to determine FT insertion length and verify gastric FT placement in infants in the neonatal intensive care unit.

RESULTS

Sixty neonatal nurses completed the survey, with 63% utilizing the nose-ear-midway to the umbilicus method, which was included in 50% of protocols and is associated with up to a 90% accuracy rate. Although it has an unacceptably high inaccuracy rate, the nose-to-ear-to-xiphoid method was used by 32% of nurses and recommended in 30% of protocols. To verify gastric FT placement, 98% of nurses used auscultation of a whoosh sound and 83% used aspiration of gastric contents. Neither verification method is supported by evidence or recommended for use.

IMPLICATIONS FOR PRACTICE

A lack of consistency exists between nursing practice and evidence-based methods.

IMPLICATIONS FOR RESEARCH

Research is needed to determine more accurate and reliable ways to determine FT insertion depth and verify gastric FT placement in neonates.

Diagnostic accuracy of a pH stick, modified to detect gastric lipase, to confirm the correct placement of nasogastric tubes

Objective

The correct placement of a nasogastric feeding tube is usually confirmed by establishing that an aspirate is acidic using a pH stick. However, antacid medication and achlorhydria can cause false negative pH tests that may delay feeding and increase resource use. The purpose of this study was to evaluate a modified pH stick designed to detect gastric lipase and therefore reduce false negative tests.

Methods

In this prospective observational study, a convenience sample of adult patients who had either gastric and oesophageal samples taken during routine diagnostic gastroscopy (n=97) or bronchial and saliva samples taken during a bronchoscopy (n=106). The samples were tested by blinded observers using the modified and standard pH sticks. The sensitivities and specificities of the two pH sticks in identifying gastric and non-gastric aspirates were compared using the pH cut-off ≤5.5.

Results

The sensitivities of a pH≤5.5 to correctly identify gastric samples were 66% (95% CI 56 to 75) and 68% (95% CI 57 to 77) for the modified and the standard pH, respectively. The specificities were 81% (95% CI 76 to 85) and 79% (95% CI 74 to 84). There were no significant differences in the distribution of the discordant results between the paired gastric and non-gastric samples for both the modified and standard pH sticks at pH≤5.5 (both McNemar’s tests, p≥0.05).

Conclusions

There were no significant differences between the paired modified and standard pH tests for the gastric samples. Due to the limited accuracy of pH sticks, further research is required to identify accurate and cost-effective bedside methods to confirm the correct placement of nasogastric tubes.

Study to determine the likely accuracy of pH testing to confirm nasogastric tube placement

Objective

To establish the likely accuracy of pH testing to identify gastric aspirates at different pH cut-offs to confirm nasogastric tube placement.

Methods

This prospective observational study included a convenience sample of adult patients who had two (one fresh and one frozen) gastric and oesophageal samples taken during gastroscopy or two bronchial and saliva samples taken during bronchoscopy. The degree of observer agreement for the pH of fresh and frozen samples was indicted by kappa (k) statistics. The sensitivities and specificities at pH ≤5.5 and the area under the receiver operating characteristics (ROC) curve at different pH cut-offs were calculated to identify gastric and non-gastric aspirates.

Results

Ninety-seven patients had a gastroscopy, 106 a bronchoscopy. There was complete agreement between observers in 57/92 (62%) of the paired fresh and frozen gastric samples (k=0.496, 95% CI 0.364 to 0.627). The sensitivity of a pH ≤5.5 to correctly identify gastric samples was 68% (95% CI 57 to 77) and the specificity was 79% (95% CI 74 to 84). The overall accuracy to correctly classify samples was between 76% and 77%, regardless of whether patients were taking antacids or not. The area under the ROC curve at different pH cut-offs was 0.74.

Conclusion

The diagnostic accuracy of pH ≤5.5 to differentiate gastric from non-gastric samples was low, regardless of whether patients were taking antacids or not. Due to the limited accuracy of the pH sticks and the operators’ ability to differentiate colorimetric results, there is an urgent need to identify more accurate and safer methods to confirm correct placement of nasogastric tubes.

A new strategy for enteral nutrition using a deflection flexible visual gastric tube: A randomized crossover manikin trial

BACKGROUND

Enteral nutrition via gastric tube insertion is a routine clinical practice for critically ill patients, although complications due to blind manipulation are occasionally reported.

METHODS

An 8.4Fr deflection flexible ureteroscope was delivered into a 15Fr conventional gastric tube to create a gastric visual guidance system. Twenty inexperienced physicians were randomly assigned to perform 5 repeated orogastric tube placements in a manikin using both the conventional method and the deflection visual gastric tube, for a total of 10 procedures per physician. Placement time, procedure-related complications, and participants' experience with both methods were recorded.

RESULTS

Under real-time guidance, the visual gastric tube successfully reached the stomach. The procedure provided additional information on the anatomy of the esophagus and stomach. Placement time was significantly less in the visual group than in the conventional group (39.39 ± 2.11 seconds vs 49.82 ± 3.11 seconds; P < .001). Procedure-related complications were not observed in the visual group; however, the gastric tube was misplaced into the airway in 19 out of 100 cases (19%) in the conventional group. Furthermore, 17 out of 20 participants (85%) preferred the visual gastric tube guide over the standard method.

CONCLUSIONS

Results of this manikin model demonstrate that it is feasible to use the deflection flexible visual gastric tube to create a route for enteral nutrition and that such a procedure decreases placement time and procedure-related complications compared to the conventional procedure. These findings may point to a new strategy for gastric tube insertion in the future.

Effect of pH Test-Strip Characteristics on Accuracy of Readings

BACKGROUND

Little is known about characteristics of colorimetric pH test strips that are most likely to be associated with accurate interpretations in clinical situations.

OBJECTIVES

To compare the accuracy of 4 pH test strips with varying characteristics (ie, multiple vs single colorimetric squares per calibration, and differing calibration units [1.0 vs 0.5]).

METHODS

A convenience sample of 100 upper-level nursing students with normal color vision was recruited to evaluate the accuracy of the test strips. Six buffer solutions (pH range, 3.0 to 6.0) were used during the testing procedure. Each of the 100 participants performed 20 pH tests in random order, providing a total of 2000 readings. The sensitivity and specificity of each test strip was computed. In addition, the degree to which the test strips under- or overestimated the pH values was analyzed using descriptive statistics.

RESULTS

Our criterion for correct readings was an exact match with the pH buffer solution being evaluated. Although none of the test strips evaluated in our study was 100% accurate at all of the measured pH values, those with multiple squares per pH calibration were clearly superior overall to those with a single test square.

CONCLUSIONS

Test strips with multiple squares per calibration were associated with greater overall accuracy than test strips with a single square per calibration. However, because variable degrees of error were observed in all of the test strips, use of a pH meter is recommended when precise readings are crucial.

Usability study of pH strips for nasogastric tube placement

AIMS

(1) To model the process of use and usability of pH strips (2) to identify, through simulation studies, the likelihood of misreading pH strips, and to assess professional's acceptance, trust and perceived usability of pH strips.

METHODS

This study was undertaken in four phases and used a mixed method approach (an audit, a semi-structured interview, a survey and simulation study). The three months audit was of 24 patients, the semi-structured interview was performed with 19 health professionals and informed the process of use of pH strips. A survey of 134 professionals and novices explored the likelihood of misinterpreting pH strips. Standardised questionnaires were used to assess professionals perceived usability, trust and acceptance of pH strip use in a simulated study.

RESULTS

The audit found that in 45.7% of the cases aspiration could not be achieved, and that 54% of the NG-tube insertions required x-ray confirmation. None of those interviewed had received formal training on pH strips use. In the simulated study, participants made up to 11.15% errors in reading the strips with important implications for decision making regarding NG tube placement. No difference was identified between professionals and novices in their likelihood of misinterpreting the pH value of the strips. Whilst the overall experience of usage is poor (47.3%), health professionals gave a positive level of trust in both the interview (62.6%) and the survey (68.7%) and acceptance (interview group 65.1%, survey group 74.7%). They also reported anxiety in the use of strips (interview group 29.7%, survey group 49.7%).

CONCLUSIONS

Significant errors occur when using pH strips in a simulated study. Manufacturers should consider developing new pH strips, specifically designed for bedside use, that are more usable and less likely to be misread.

Testing Placement of Gastric Feeding Tubes in Infants

BACKGROUND

Inadvertent positioning of a nasogastric tube in the lung can cause serious complications, so identifying methods to detect improperly inserted tubes is imperative.

OBJECTIVES

To compare the sensitivity, specificity, and negative and positive predictive values of 4 pH cut points (< 4.0, < 4.5, < 5.0, and < 5.5) in differentiating gastric and tracheal aspirates under various treatment conditions and to explore the utility of a pepsin assay for distinguishing between gastric and tracheal aspirates.

METHODS

Gastric and tracheal aspirates were collected from critically ill infants undergoing mechanical ventilation who had nasogastric or orogastric feeding tubes. Aspirates were tested with colorimetric pH indicators and a rapid pepsin assay. Information about treatment conditions was obtained from medical records.

RESULTS

Two hundred twelve gastric aspirates and 60 tracheal aspirates were collected from 212 patients. Sensitivity was highest and specificity was lowest at the gastric aspirate pH cut point of less than 5.5. Positive predictive values were 100% at all pH cut points less than 5.0. Negative predictive values were higher at the pH cut point of less than 5.0 than at cut points less than 4.5. A higher percentage of pepsin-positive readings was found in gastric aspirates (88.3%) than in tracheal aspirates (5.4%).

CONCLUSION

For a desired positive predictive value of 100%, a pH cut point of less than 5.0 provides the best negative predictive values, regardless of gastric acid inhibitor administration and feeding status. The pepsin assay is promising as an additional marker to distinguish gastric from tracheal aspirates.

Use of Nasogastric Feeding Tubes for Children at Home: A Template for Caregiver Education

There is a lack of knowledge on the part of caregivers who need to place nasogastric (NG) tubes in children for enteral nutrition therapy. This article provides the rationale, best practices, and a template for caregiver education. Canadian and Australian programs have excellent patient education materials. They have shared these step-by-step procedures for healthcare professionals to provide to caregivers to whom they are teaching placement and care of NG tubes.

Current Practices in Home Management of Nasogastric Tube Placement in Pediatric Patients: A Survey of Parents and Homecare Providers

Enteral feeding tubes are used in pediatric patients to deliver nutrition, fluids or medications. The literature related to short-term feeding tube (nasogastric [NG], hereafter known as NGT, or orogastric [OGT],) use in pediatric homecare patients is sparse. This descriptive study sought to gather baseline information about these children and how their feeding tubes are managed at home. Specifically, we sought to better understand how the tubes are placed and the method(s) used for tube placement verification. Two surveys were distributed: one to parents and one to homecare providers who have direct patient contact.

RESULTS

Responses were obtained from 144 parents and 66 homecare providers. Over half of the children were 12months of age or younger and had a 6 Fr feeding tube. Over 75% (108) had an NGT for 1year or less. Predominantly parents replaced the NGT but a few children self-inserted their tubes. Feeding tube placement was verified by auscultation (44%) or measurement of gastric pH (25%) in the parent's survey. Twenty-six percent of parents indicated they had misplaced an NGT at least once and 35 parents described symptoms of pulmonary misplacement. The homecare provider data indicated auscultation (39%) and pH measurement of gastric contents (28%) to verify NG tube placement location. Study results confirms a need for consistency of practice among health care professionals and in parent education for those children who require NGTs at home. It is troubling that auscultation is still widely used for NGT location confirmation despite practice alerts that warn against its use.

ASPEN Safe Practices for Enteral Nutrition Therapy [Formula: see text]

Enteral nutrition (EN) is a valuable clinical intervention for patients of all ages in a variety of care settings. Along with its many outcome benefits come the potential for adverse effects. These safety issues are the result of clinical complications and of process-related errors. The latter can occur at any step from patient assessment, prescribing, and order review, to product selection, labeling, and administration. To maximize the benefits of EN while minimizing adverse events requires that a systematic approach of care be in place. This includes open communication, standardization, and incorporation of best practices into the EN process. This document provides recommendations based on the available evidence and expert consensus for safe practices, across each step of the process, for all those involved in caring for patients receiving EN.

Does Bedside Sonography Effectively Identify Nasogastric Tube Placements in Pediatric Critical Care Patients?

BACKGROUND

A nasogastric tube (NGT) insertion is a common procedure in intensive care units, with some serious complications that result from the malposition of the NGT tip. This pilot study was designed to investigate the efficiency of ultrasound in verifying correct NGT placement and to compare these results with radiographic findings.

MATERIALS AND METHODS

This was a single-center, double-blind prospective study of patients who had received an NGT in the pediatric critical care unit. Twenty-one patients aged 1 month to 18 years were included in this study. All NGTs were inserted by the same critical care physician. After insertion, the physician first confirmed NGT placement by the auscultation of the epigastrium following the insufflation of air. Confirmation was supplemented with an abdominal radiograph. A radiologist who was unaware of the radiographic findings performed bedside sonography on all patients and verified the location of the NGTs. The findings from these 2 physicians were then compared.

RESULTS

NGTs were inserted without any complications, and none of the NGTs were positioned in the respiratory tract in any of the patients. All NGT tips were visualized by radiography and sonography with a sensitivity of 100%.

CONCLUSION

Bedside sonography performed by a radiologist is an effective and sensitive diagnostic procedure for confirming the correct NGT position in patients in the pediatric critical care unit.

Naso-enteric Tube Placement: A Review of Methods to Confirm Tip Location, Global Applicability and Requirements

BACKGROUND

The insertion of a tube through the nose and into the stomach or beyond is a common clinical procedure for feeding and decompression. The safety, accuracy and reliability of tube insertion and methods used to confirm the location of the naso-enteric tube (NET) tip have not been systematically reviewed. The aim of this study is to review and compare these methods and determine their global applicability by end-user engagement.

METHODS

A systematic literature review of four major databases was performed to identify all relevant studies. The methods for NET tip localization were then compared for their accuracy with reference to a gold standard method (radiography or endoscopy). The global applicability of the different methods was analysed using a house of quality matrix.

RESULTS

After applying the inclusion and exclusion criteria, 76 articles were selected. Limitations were found to be associated with the 20 different methods described for NET tip localization. The method with the best combined sensitivity and specificity (where n > 1) was ultrasound/sonography, followed by external magnetic guidance, electromagnetic methods and then capnography/capnometry. The top three performance criteria that were considered most important for global applicability were cost per tube/disposable, success rate and cost for non-disposable components.

CONCLUSION

There is no ideal method for confirming NET tip localisation. While radiography (the gold standard used for comparison) and ultrasound were the most accurate methods, they are costly and not universally available. There remains the need to develop a low-cost, easy-use, accurate and reliable method for NET tip localization.

The pH of Feeding Tube Aspirates From Critically Ill Infants

BACKGROUND

The extent to which gastric acid inhibitors and feedings affect gastric pH in infants is unclear.

OBJECTIVES

To compare pH values of gastric aspirates from infants according to use or no use of gastric acid inhibitors and feedings.

METHODS

Colorimetric pH tests were used to measure the pH of aspirates from feeding tubes in 54 critically ill infants; 29 of the gastric aspirates were from infants who did not receive acid inhibitors or feedings, 13 were from infants who received acid inhibitors but no feedings, 3 were from infants who received feedings but no acid inhibitors, and 5 were from infants who received both acid inhibitors and feedings. The remaining 4 feeding tubes were in nongastric sites.

RESULTS

Individual pH readings of 5.5 or less were found in 97% of the gastric aspirates from infants with no recent feedings or acid inhibitors, 77% of the gastric aspirates from infants who received acid inhibitors, and 67% of the gastric aspirates from infants with recent feedings. Among 2 esophageal aspirates and 2 duodenal aspirates, 1 of each type had a pH less than 5.5. A pH cut point of 5.5 or less did not rule out esophageal or duodenal placement.

CONCLUSIONS

The pH of gastric aspirates from critically ill infants is often 5.5 or less, regardless of the use of acid inhibitors, feedings, or both. Most likely a cut point of 5.5 or less would rule out respiratory placement because tracheal pH is typically 6.0 or higher.

Following the evidence: enteral tube placement and verification in neonates and young children

Enteral tube placement in hospitalized neonates and young children is a common occurrence. Accurate placement and verification are imperative for patient safety. However, despite many years of research that provides evidence for a select few methods and clearly discredits the safety of others, significant variation in clinical practice is still common. Universal adoption and implementation of evidence-based practices for enteral tube placement and verification are necessary to ensure consistency and safety of all patients. This integrative review synthesizes current and seminal literature regarding the most accurate enteral tube placement and verification methods and proposes clinical practice recommendations.

Use of Temporary Enteral Access Devices in Hospitalized Neonatal and Pediatric Patients in the United States

BACKGROUND

Temporary enteral access devices (EADs), such as nasogastric (NG), orogastric (OG), and postpyloric (PP), are used in pediatric and neonatal patients to administer nutrition, fluids, and medications. While the use of these temporary EADs is common in pediatric care, it is not known how often these devices are used, what inpatient locations have the highest usage, what size tube is used for a given weight or age of patient, and how placement is verified per hospital policy.

MATERIALS AND METHODS

This was a multicenter 1-day prevalence study. Participating hospitals counted the number of NG, OG, and PP tubes present in their pediatric and neonatal inpatient population. Additional data collected included age, weight and location of the patient, type of hospital, census for that day, and the method(s) used to verify initial tube placement.

RESULTS

Of the 63 participating hospitals, there was an overall prevalence of 1991 temporary EADs in a total pediatric and neonatal inpatient census of 8333 children (24% prevalence). There were 1316 NG (66%), 414 were OG (21%), and 261 PP (17%) EADs. The neonatal intensive care unit (NICU) had the highest prevalence (61%), followed by a medical/surgical unit (21%) and pediatric intensive care unit (18%). Verification of EAD placement was reported to be aspiration from the tube (n = 21), auscultation (n = 18), measurement (n = 8), pH (n = 10), and X-ray (n = 6).

CONCLUSION

The use of temporary EADs is common in pediatric care. There is wide variation in how placement of these tubes is verified.

Nasogastric tube placement and verification in children: review of the current literature

Placement of a nasogastric enteral access device (NG-EAD), often referred to as a nasogastric tube, is a common practice and largely in the domain of nursing care. Most often an NG-EAD is placed at the bedside without radiographic assistance. Correct initial placement and ongoing location verification are the primary challenges surrounding NG-EAD use and have implications for patient safety. Although considered an innocuous procedure, placement of an NG-EAD carries risk of serious and potentially lethal complications. Despite acknowledgment that an abdominal radiograph is the gold standard, other methods of verifying placement location are widely used and have success rates from 80% to 85%. The long-standing challenges surrounding bedside placement of NG-EADs and a practice alert issued by the Child Health Patient Safety Organization on this issue were the stimuli for the conception of The New Opportunities for Verification of Enteral Tube Location Project sponsored by the American Society for Parenteral and Enteral Nutrition. Its mission is to identify and promote best practices with the potential of technology development that will enable accurate determination of NG-EAD placement for both the inpatient and outpatient pediatric populations. This article presents the challenges of bedside NG-EAD placement and ongoing location verification in children through an overview of the current state of the science. It is important for all healthcare professionals to be knowledgeable about the current literature, to be vigilant for possible complications, and to avoid complacency with NG-EAD placement and ongoing verification of tube location.