Accuracy of the 7-8-9 Rule for endotracheal tube placement in the neonate

[Characteristics of the fetal and infant respiratory system : What the pediatric anesthetist should know]

Respiratory complications are the most frequent incidents in pediatric anesthesia after cardiac events. The pediatric respiratory physiology and airway anatomy are responsible for the particular respiratory vulnerability in this stage of life. This article explains the aspects of pulmonary embryogenesis relevant for anesthesia and their impact on the respiration of preterm infants and neonates. The respiratory distress syndrome and bronchopulmonary dysplasia are highlighted as well as the predisposition to apnea of preterm infants and neonates. Due to the anatomical characteristics, the low size ratios and the significantly shorter apnea tolerance, airway management in children frequently represents a challenge. This article gives useful assistance and provides an overview of formulas for calculating the appropriate tube size and depth of insertion. Finally, the pathophysiology and adequate treatment of laryngospasm are explained.

Airway management in neonates and infants: European Society of Anaesthesiology and Intensive Care and British Journal of Anaesthesia joint guidelines

Airway management is required during general anaesthesia and is essential for life-threatening conditions such as cardiopulmonary resuscitation. Evidence from recent trials indicates a high incidence of critical events during airway management, especially in neonates or infants. It is important to define the optimal techniques and strategies for airway management in these groups. In this joint European Society of Anaesthesiology and Intensive Care (ESAIC) and British Journal of Anaesthesia (BJA) guideline on airway management in neonates and infants, we present aggregated and evidence-based recommendations to assist clinicians in providing safe and effective medical care. We identified seven main areas of interest for airway management: i) preoperative assessment and preparation; ii) medications; iii) techniques and algorithms; iv) identification and treatment of difficult airways; v) confirmation of tracheal intubation; vi) tracheal extubation, and vii) human factors. Based on these areas, Population, Intervention, Comparison, Outcomes (PICO) questions were derived that guided a structured literature search. GRADE (Grading of Recommendations, Assessment, Development and Evaluation) methodology was used to formulate the recommendations based on those studies included with consideration of their methodological quality (strong '1' or weak '2' recommendation with high 'A', medium 'B' or low 'C' quality of evidence). In summary, we recommend: 1. Use medical history and physical examination to predict difficult airway management (1C). 2. Ensure adequate level of sedation or general anaesthesia during airway management (1B). 3. Administer neuromuscular blocker before tracheal intubation when spontaneous breathing is not necessary (1C). 4. Use a videolaryngoscope with an age-adapted standard blade as first choice for tracheal intubation (1B). 5. Apply apnoeic oxygenation during tracheal intubation in neonates (1B). 6. Consider a supraglottic airway for rescue oxygenation and ventilation when tracheal intubation fails (1B). 7. Limit the number of tracheal intubation attempts (1C). 8. Use a stylet to reinforce and preshape tracheal tubes when hyperangulated videolaryngoscope blades are used and when the larynx is anatomically anterior (1C). 9. Verify intubation is successful with clinical assessment and end-tidal CO2 waveform (1C). 10. Apply high-flow nasal oxygenation, continuous positive airway pressure or nasal intermittent positive pressure ventilation for postextubation respiratory support, when appropriate (1B).

Airway management in neonates and infants: European Society of Anaesthesiology and Intensive Care and British Journal of Anaesthesia joint guidelines

Airway management is required during general anaesthesia and is essential for life-threatening conditions such as cardiopulmonary resuscitation. Evidence from recent trials indicates a high incidence of critical events during airway management, especially in neonates or infants. It is important to define the optimal techniques and strategies for airway management in these groups. In this joint European Society of Anaesthesiology and Intensive Care (ESAIC) and British Journal of Anaesthesia (BJA) guideline on airway management in neonates and infants, we present aggregated and evidence-based recommendations to assist clinicians in providing safe and effective medical care. We identified seven main areas of interest for airway management: i) preoperative assessment and preparation; ii) medications; iii) techniques and algorithms; iv) identification and treatment of difficult airways; v) confirmation of tracheal intubation; vi) tracheal extubation, and vii) human factors. Based on these areas, Population, Intervention, Comparison, Outcomes (PICO) questions were derived that guided a structured literature search. GRADE (Grading of Recommendations, Assessment, Development and Evaluation) methodology was used to formulate the recommendations based on those studies included with consideration of their methodological quality (strong '1' or weak '2' recommendation with high 'A', medium 'B' or low 'C' quality of evidence). In summary, we recommend: 1. Use medical history and physical examination to predict difficult airway management (1С). 2. Ensure adequate level of sedation or general anaesthesia during airway management (1B). 3. Administer neuromuscular blocker before tracheal intubation when spontaneous breathing is not necessary (1С). 4. Use a videolaryngoscope with an age-adapted standard blade as first choice for tracheal intubation (1B). 5. Apply apnoeic oxygenation during tracheal intubation in neonates (1B). 6. Consider a supraglottic airway for rescue oxygenation and ventilation when tracheal intubation fails (1B). 7. Limit the number of tracheal intubation attempts (1C). 8. Use a stylet to reinforce and preshape tracheal tubes when hyperangulated videolaryngoscope blades are used and when the larynx is anatomically anterior (1C). 9. Verify intubation is successful with clinical assessment and end-tidal CO 2 waveform (1C). 10. Apply high-flow nasal oxygenation, continuous positive airway pressure or nasal intermittent positive pressure ventilation for postextubation respiratory support, when appropriate (1B).

Can Intubation Be Improved with Endotracheal Tubes Marked with a Color Scale? Randomized Controlled Study

OBJECTIVE

This study aimed to assess if a color scale in the endotracheal tube (ETT) can help operators to correctly select the size and depth of placement of the ETT and decrease the time required to complete the procedure and compared with the usual numeric ETT scale in a mannequin model.

STUDY DESIGN

The study was conducted in eight centers. Each size of the ETT was identified with a different color. The experimental ETTs had two different colored areas, one for the mouthpiece and another to identify where the ETT should be taped above the lip (an area of 1 cm. The operators were trained as part of the protocol using an instructional video. Four clinical scenarios requiring endotracheal intubation were designed and randomly assigned. Each operator had to select the size and depth of ETT based on the birth weight (BW), and then had to perform four intubations.

RESULTS

A total of 108 operators performed 432 intubations. No differences were found in the correct placement and selection of the ETT. Median time (in seconds) required for intubation using numeric versus experimental tube was: for ETT Ø NRP (Neonatal Resuscitation Program) 2.5, 11.5 versus 8 (p < 0.001), ETT Ø 3, 12 versus 10 (p < 0.001), ETT Ø 3.5, 15.5 versus12 (p = 0.003), ETT Ø 4, 12 versus11 (p = 0.019).

CONCLUSION

No significant difference was observed in the selection and correct placement of the ETT. However, the intubation time was significantly shorter using the experimental ETT. This device could improve the effectiveness of intubation by reducing the time needed to properly place the ETT at mid trachea.

KEY POINTS

· It is an innovative intervention to try to solve a great inconvenience of daily practice.. · The study also raises the difficulty in maintaining the ability of endotracheal intubation.. · It proposes a scale that ensures the correct location with a safe fixation zone..

Indications, Measurements, and Complications of Ten Essential Neonatal Procedures

About 10% of newborns require some degree of assistance to begin their breathing, and 1% necessitates extensive resuscitation. Sick neonates are exposed to a number of invasive life-saving procedures as part of their management, either for investigation or for treatment. In order to support the neonates with the maximum possible benefits and reduce iatrogenic morbidity, health-care providers performing these procedures must be familiar with their indications, measurements, and potential complications. Hence, the aim of this review is to summarise ten of the main neonatal intensive care procedures with highlighting of their indications, measurements, and complications. They include the umbilical venous and arterial catheterizations and the intraosseous line which represent the principal postnatal emergency vascular accesses; the peripherally inserted central catheter for long-term venous access; the endotracheal tube and laryngeal mask airway for airway control and ventilation; chest tube for drainage of air and fluid from the thorax; and the nasogastric/orogastric tube for enteral feeding. Furthermore, lumber puncture and heel stick were included in this review as very important and frequently performed diagnostic procedures in the neonatal intensive care unit.

Utilizing nasal-tragus length to estimate optimal endotracheal tube depth in neonates: A prospective randomized control study

BACKGROUND

Determination of the optimal depth of endotracheal tube insertion in neonates is challenging. Various formulae have been proposed and are being commonly used for this purpose. There is no single formula that is ideal or can be applied across different populations.

AIM

To compare weight and nasal-tragus length-based formulae as a guide to endotracheal tube insertion depth in term neonates undergoing surgery. Ther primary objective of the study was to determine the position of the endotracheal tube using either weight-based or nasal-tragus length-based formulae and the secondary objective was to determine the incidence of repositioning of the endotracheal tube.

METHODS

A total of 120 full term neonates were divided into two groups with 60 neonates each (group N = NTL + 1 cm and group W = Weight + 6 cm). Endotracheal tube was inserted according to the pre-calculated value and fixed. A neonatal flexible fiberoptic bronchoscope was used to confirm the position of the endotracheal tube tip by measuring its distance from the carina. Repositioning was done if the distance from carina to endotracheal tube tip was less than 20 mm. Chi-squared and Mann-Whitney tests were used for the analysis.

RESULTS

The mean distance measured from carina to endotracheal tube tip in group N was 9.41 ± 6.65 mm and in group W was 3.21 ± 3.45 mm (p value = <.001). A higher incidence of optimal endotracheal tube placement was observed in group N which led to repositioning in 88.3% of neonates in group N and 100% in the group W (53/60 and 60/60, respectively, p value < .05).

CONCLUSION

Based on the results from the studied sample, NTL +1 cm formula is a better predictor than Weight + 6 cm formula to determine endotracheal tube insertion depth in term Indian neonates.

Assessment of the Endotracheal Tube Tip Position by Bedside Ultrasound in a Pediatric Intensive Care Unit: A Cross-sectional Study

Introduction

The chest X-ray (CXR) is the standard of practice to assess the tip of the endotracheal tube (ETT) in ventilated children. In many hospitals, it takes hours to get a bedside CXR, and it has radiation exposure. The objective of this study was to find the utility of bedside ultrasound (USG), in assessing the ETT tip position in a Pediatric Intensive Care Unit (PICU).

Methods

It was a prospective study conducted in the PICU of a tertiary care center involving 135 children aged from 1 month to 60 months, requiring endotracheal intubation. In this study, the authors compared the position of the ETT tip by the CXR (gold standard) and USG. The CXR was taken in children to assess the correct position of the tip of ETT. The USG was used to measure the distance between the tip of ETT and the arch of the aorta, thrice in the same patient. The mean of the three USG readings was compared with the distance between the tip of the ETT and carina in CXR.

Results

The reliability of three USG readings was tested by absolute agreement coefficient in intraclass correlation (ICC), 0.986 (95% CI: 0.981-0.989). The sensitivity and specificity of the USG in identifying the correct position of the ETT tip in children when compared to CXR were 98.10% (95% CI: 93.297-99.71%) and 50.0% (95% CI: 31.30-68.70%), respectively.

Conclusion

In ventilated children <60 months of age, identifying the tip of ETTs by bedside the USG has good sensitivity (98.10%) but poor specificity (50.0%).

How to cite this article

Subramani S, Parameswaran N, Ananthkrishnan R, Abraham S, Chidambaram M, Rameshkumar R, et al. Assessment of the Endotracheal Tube Tip Position by Bedside Ultrasound in a Pediatric Intensive Care Unit: A Cross-sectional Study. Indian J Crit Care Med 2022;26(11):1218-1224.

Randomised trial estimating length of endotracheal tube insertion using gestational age or nasal-tragus length in newborns: a study protocol

INTRODUCTION

Endotracheal tube (ETT) insertion depth estimation is important for optimal placement of ETT tip and balanced ventilation of the lungs. Various methods are available to determine the ETT insertion depth. The Neonatal Resuscitation Programme recommends the gestational age and nasal-tragus length (NTL) methods for estimating ETT insertion depth during cardiopulmonary resuscitation. However, the prospective data comparing these two methods is lacking.

METHODS AND ANALYSIS

This is an open-label multi-centre randomised controlled trial, where gestational age and NTL methods will be used to determine the initial ETT insertion depth in term and preterm infants that are less than 28 days old, requiring oral intubation in the delivery room or neonatal intensive care unit (NICU).

SITES AND SAMPLE SIZE

The trial is aimed to recruit 454 infants over 3 years across tertiary level NICUs.

OUTCOMES

The primary outcome includes an optimally positioned ETT, defined as an ETT tip between the upper border of the first thoracic vertebra and the lower border of the second thoracic vertebra. The outcome is assessed by a paediatric radiologist, who will be masked to the group assignment. Secondary outcomes are malpositioned ETT tips, pneumothorax, ETT repositioning, chronic lung disease, invasive ventilation days, and death.

ANALYSIS

Data will be analysed using the intention-to-treat principle. The primary and categorical secondary outcomes will be compared using the χ² test. Adjusted risk ratios of outcomes will be calculated along with 95% CIs through multivariable logistic regression analysis, including covariates deemed biologically to influence the outcomes.

ETHICS AND DISSEMINATION

The study has been approved by the PNU Research Ethics Board (20-0148) and the respective ethical review boards of the participating centres. The results will be disseminated through conference meetings, social media platforms, and publications in scientific journals.

TRIAL REGISTRATION NUMBER

NCT04393337.

Singapore Neonatal Resuscitation Guidelines 2021

Neonatal resuscitation is a coordinated, team-based series of timed sequential steps that focuses on a transitional physiology to improve perinatal and neonatal outcomes. The practice of neonatal resuscitation has evolved over time and continues to be shaped by emerging evidence as well as key opinions. We present the revised Neonatal Resuscitation Guidelines for Singapore 2021. The recommendations from the International Liaison Committee on Resuscitation Neonatal Task Force Consensus on Science and Treatment Recommendations (2020) and guidelines from the American Heart Association and European Resuscitation Council were compared with existing guidelines. The recommendations of the Neonatal Subgroup of the Singapore Resuscitation and First Aid Council were derived after the work group discussed and appraised the current available evidence and their applicability to local clinical practice.

Methods for Estimating Endotracheal Tube Insertion Depth in Neonates: A Systematic Review and Meta-Analysis

OBJECTIVE

To systematically review the methods for estimating endotracheal tube (ETT) insertion depth in neonates.

STUDY DESIGN

Medline, Embase, Cochrane Central, and Cumulative Index to Nursing and Allied Health Literature databases searched for randomized clinical trials (RCTs). RCTs comparing two or more different methods to estimate ETT insertion depth were included. Two co-authors independently extracted the data and assessed the risk of bias. The primary outcome includes the proportion of optimally placed ETT tips identified on chest X-ray.

RESULTS

Eight RCTs evaluating seven different estimation methods were included. Trials varied defining the optimal position of the ETT tip. Overall, the percentage of optimal position ranged from 8.8 to 93%. The weight, gestation nomogram, and vocal cord estimation methods resulted in malpositioning of ETT tips in more than half of infants ≤30 weeks' gestational age. The rates of optimal ETT tip placement with the digital palpation method differ between moderately (83-93%; two RCTs) and extremely (47%; one RCT) preterm infants. Meta-analysis showed no difference between weight-based and digital palpation methods (relative risk = 0.88; 95% confidence interval = 0.75-1.04; three RCTs; participants = 205; I ² = 0%; quality of evidence, low).

CONCLUSION

Commonly used estimation methods for ETT tip placement are inaccurate and unreliable. Further research is required to improve the accuracy of estimation methods and also to identify the usefulness of the digital palpation method in large clinical trials.

Is Nasal Septum-Tragus Length Measurement Appropriate for Endotracheal Tube Intubation Depth in Neonates? A Randomized Controlled Study

OBJECTIVE

Endotracheal intubation is a frequent procedure performed in neonates with respiratory distress. Clinicians use different methods to estimate the intubation insertion depth, but, unfortunately, the improper insertion results are very high. In this study, we aimed to compare the two different methods (Tochen's formula = weight in kilograms + 6 cm; and nasal septum-tragus length [NTL] + 1 cm) used to determine the endotracheal tube (ETT) insertion depth.

STUDY DESIGN

Infants who had intubation indications were enrolled in this study. The intubation tube was fixed using the Tochen formula (Tochen group) or the NTL + 1 cm formula (NTL group). After intubation, the chest radiograph was evaluated (above T1, proper place, and below T2).

RESULTS

A total of 167 infants (22-42 weeks of gestational age) were included in the study. The proper tube placement rate in both groups was similar (32.4 vs. 30.4% for infants < 34 weeks of gestational age and 56.8 vs. 45.0% in infants > 34 weeks of gestational age). The ETT was frequently placed below T2 at a higher rate in infants with a gestational age of <34 weeks, especially in the NTL group (46% in the Tochen group and 60.7% in the NTL group).

CONCLUSION

The NTL + 1 cm formula led to a higher rate of ETT placement below T2, especially in infants with a birth weight of <1,500 g. Therefore, more studies are needed to determine the optimal ETT insertion depth.

'Lip-to-Tip' study: comparison of three methods to determine optimal insertion length of endotracheal tube in neonates

The aim of this prospective observational study was to compare the incidence of endotracheal tube (ETT) malposition using weight-based (Tochen), gestation-based (Kempley), and nasotragal length (NTL) methods in deceased neonates and fresh stillbirths. We enrolled deceased neonates and fresh stillbirths within 2 ± 1 h of death or delivery, respectively; without hydrops, tracheostomy or major congenital anomalies affecting face, neck, or thorax. Each enrolled subject was intubated orotracheally, with lip-to-tip distance determined by three methods in random succession. Chest X-ray was acquired after each insertion. The primary outcome was proportion of malpositioned ETTs on chest X-ray (defined as ETT tip not lying between upper border of T1 and lower border of T2 vertebrae), assessed by two experts masked to the methods used. The proportion of malpositioned tubes was not significantly different with any of the three methods: (weight 27/50 (54%), gestation 35/50 (70%), and NTL 35/50 (70%), p value 0.055). The malpositioned tubes were too far in (87/150; 58%) than too far out (10/150; 6.7%).Conclusions: None of the currently recommended methods accurately predicts optimal ETT length in neonates. There is an urgent need for newer bedside modalities for estimating ETT position in neonates. What is known? • NRP guidelines recommend gestation-based and nasotragal length (NTL) methods to estimate initial ETT depth in neonates. Weight-based (Tochen) method is still widely used in neonatal units for ETT depth estimation. Evidence till date has not proven superiority of one method over the other. What is new? • All three methods for ETT depth estimation (Tochen, gestation-based, and NTL) resulted in high rates of ETT malposition in neonates. Formulae, devised from this study based on linear regression models, did not perform well for estimation of optimal ETT position.

Weight Is More Accurate than Gestational Age When Estimating the Optimal Endotracheal Tube Depth in Neonates

Determining the optimal endotracheal tube (ETT) depth in neonates remains challenging for neonatologists. The guideline for optimal ETT depth is based on the patients’ weight or gestational age. However, there is a discrepancy in the suggested ETT depth between these two parameters. The aim of this retrospective study was to compare the recommended weight-based and age-based formulas for optimal ETT depth and obtain the optimal reference before intubation. Participants were assigned to group 1 if the recommended ETT insertion depth based on weight was concordant with the recommended depth based on gestational age, and to group 2 if the weight and age-based depth recommendations were discordant. After exclusion, 180 patients were included in the analysis. Results indicated that the predicted ETT depth suggested by age required more adjustment than by weight (p < 0.05). Furthermore, the required adjustment in the weight-based formula was smaller than the age-based formula (p < 0.05). Multivariate linear regression analysis revealed that weight was the key factor affecting the optimal depth (p < 0.001). These results imply that when there is a discrepancy in ETT depth between the weight-based and age-based recommendation, the weight-based one will be more accurate than the age-based one.

New Formula for Nasal Endotracheal Intubation in Extremely Low-Birth Weight Infants in the Emergency Transport Setting: The "Genoa Formula"

OBJECTIVE

The purpose of this study was to find a predictive equation for estimating the optimal nasal endotracheal tube insertion depth in extremely low-birth weight infants (ELBWs) requiring invasive ventilation in the critical care interfacility transport setting.

METHODS

We retrospectively calculated the optimal tube insertion depth in a cohort of neonates ≤ 1,000 g born at our neonatal intensive care unit and nasally intubated within the first 24 hours of life from January 2019 to May 2020.

RESULTS

A total of 75 ELBW infants were included, with a median gestational age of 26.6 weeks (range, 22.1-32.6 weeks) and a median birth weight of 780 g (range, 410-990 g). The linear regression of the estimated optimal endotracheal tube insertion depth showed a good correlation when plotted against weight (R² = 0.491); thus, a new weight-based formula was obtained.

CONCLUSION

The proposed weight-based formula (the "Genoa formula") may help in predicting optimal insertion depths for nasal intubation in ELBW neonates, especially when a prompt radiologic confirmation of the tube position is not available, as during neonatal critical care transport.

Nasal insertion depths for neonatal intubation

AIM

Data on the depth of nasal intubation in neonates are rare, although this is the preferred route in some countries. Therefore, recommendations on optimal nasal intubation depths based on gestational age (GA) and weight are desirable.

METHODS

We determined the distances between the middle of thoracic vertebrae 2 (T2) and the tip of the endotracheal tube in 116 X-rays from nasally intubated neonates. The intubation depth (tip to nostril distance) that was documented in the digital patient's file was then corrected for this distance to reach an optimal nasal insertion depth. Results were plotted against the infant's GA and weight.

RESULTS

GA-based and birthweight-based charts and formulas for the nasal intubation depth in infants with a GA between 24 and 43 weeks and body weight between 400 and 4500 g were created.

CONCLUSIONS

Generated data may help in predicting optimal insertion depths for nasal intubation in neonates.

Accuracy of various recent recommendations to estimate the optimal depth of orotracheal tube in Thai neonates

BACKGROUND

Malposition of an endotracheal tube (ETT) may lead to many serious consequences. Recently, various methods have been proposed to estimate the proper position of orotracheal intubation (Pro-depth) for neonates.

OBJECTIVES

To determine and compare the accuracy of various methods for estimating the Pro-depth and to define the most accurate method for the Asian population.

METHOD

This cross-sectional study was conducted at the Chiang Mai University Hospital, Thailand in Asian neonates who required orotracheal intubation and their ETT's position were confirmed with anteroposterior chest radiographs. The estimated depths of orotracheal tubes (Est-depth) were calculated by using 4 methods: the rule of 7-8-9, NTL + 1 cm, corrected gestational age (GA)-based table, and body weight (BW)-based table. We defined the Pro-depth as the depth which provided the ETT's tip placed at mid trachea. The Pearson's correlation coefficient, the Bland-Altmann plot and mean differences with standard deviation (SD) between paired Est-depth by each method and Pro-depth were determined. New formulae were generated to estimate the Pro-depth based on a linear regression equation. The accuracy of each method to predict the optimal depth of orotracheal intubation (Opt-depth) was calculated.

RESULTS

Fifty-eight Asian neonates were enrolled of which, 82.8% were Thai. The mean ± SD of GA and BW were 33 ± 5 weeks and 1562 ± 842 g, respectively. NTL + 1 cm and the Pro-depth showed the strongest correlation (r = 0.90, p-value < .01) and agreement with mean difference ± SD of 0.28 ± 0.53 cm. The accuracies of the rule of 7-8-9, NTL + 1cm, corrected GA-based and BW-based table to predict the Opt-depth were 56.9%, 63.8%, 62.1%, and 60.3%, respectively. We created two simple formulae for our population to increase the accuracy of NTL parameter: NTL + 1 cm for measured NTL ≤ 6.5 cm and NTL + 0.5 cm for measured NTL > 6.5 cm. This new method provided more accuracy (72.4%) with mean difference ± SD of -0.03 ± 0.53 cm.

CONCLUSION

NTL was the most suitable parameter for estimating the Pro-depth. Our new modified NTL method should be used for Thai neonates with high accuracy and non-significantly underestimated trend. However, promptly clinical assessment and final confirmation by a chest radiography should be done in all intubated patients.

Ideal endotracheal tube insertion depth in neonates with a birthweight less than 750 g

BACKGROUND

Appropriate management of the endotracheal tube (ETT) insertion depth is important. The depth calculated using Tochen's formula is overestimated in extremely-low- birthweight infants, particularly those with a birthweight <750 g. Gestational age has been shown to be particularly useful in the Neonatal Resuscitation Program, 7th edition.⁵ However, a randomized trial for estimating the ETT insertion depth failed to show the advantage of using gestational age over birthweight.⁶ Therefore, we aimed to estimate the appropriate ETT insertion depth in neonates weighing <750 g.

METHODS

This was a single-center, retrospective observational study including neonates weighing <750 g who required intubation. The appropriate depth was determined by adjusting the distance between the actual ETT position and the area from the first to the second thoracic vertebra on the radiograph. Correlations between gestational age and physique were investigated using Pearson's correlation coefficient. We examined small-for- gestational-age (SGA) infants and non-SGA infants separately.

RESULTS

Forty neonates were enrolled in this study. The mean gestational age and birthweight were 26.3 weeks and 620 g respectively. Twenty infants were SGA. The ETT position was deep in 35 of 40 cases, with the strongest correlation between weight and ETT insertion depth. The correlation with gestational age was not observed in this study.

CONCLUSIONS

Our study showed that the ideal ETT insertion depth at birth correlates with birthweight in neonates weighing <750 g. Therefore, determination by gestational age may not be feasible in populations with a high proportion of SGA infants.

Nasal-tragus length for estimating optimal insertion depth of endotracheal tube in Thai neonates

OBJECTIVE

To develop a nasal-tragus length (NTL)-based table for estimating the endotracheal tube (ETT) insertion depth.

STUDY DESIGN

A prospective study of 110 Thai neonates was conducted in a NICU in Bangkok, Thailand. The correlation between the optimal insertion depth (Opt-Depth) and NTL was determined, and then an NTL-based table for estimating ETT depth was developed. The accuracy of using various methods in estimating ETT depth was compared.

RESULTS

A strong correlation between Opt-Depth and NTL was found (r = 0.897, p < 0.001). There was no significant difference between ETT depth estimated by the NTL-based table and Opt-Depth [mean difference (95% CI) -0.75 (-12.11 to 10.61) mm, p = 0.22]. The accuracies of using NTL + 1, NTL-based, GA-based, and BW-based tables for estimating ETT depth were 32.7%, 55.5%, 61.8%, and 52.7%, respectively.

CONCLUSION

Our NTL-based table for estimating the ETT depth had an acceptable accuracy while using "NTL + 1" resulted in overestimating ETT depth.

Randomised trial of estimating oral endotracheal tube insertion depth in newborns using suprasternal palpation of the tip or weight

BACKGROUND

Endotracheal tube (ETT) tip position is determined on chest X-ray (CXR) and should lie between the upper border of the first thoracic vertebra (T1) and the lower border of second thoracic vertebra (T2). Infant weight is commonly used to estimate how far the ETT should be inserted but frequently results in malpositioned ETT tips. Palpation of the ETT tip at the suprasternal notch has been recommended as an alternative.

OBJECTIVE

To determine whether estimating ETT insertion depth using suprasternal palpation of the ETT tip rather than weight results in more correctly positioned ETT tips.

DESIGN

Single-centre randomised controlled trial.

SETTING

Level III neonatal intensive care unit (NICU) at a university maternity hospital.

PATIENTS

Newborn infants without congenital anomalies intubated in the NICU.

INTERVENTIONS

Participants were randomised to have ETT insertion depth estimated using palpation of the ETT tip at the suprasternal notch or weight [insertion depth (cm)=6 + wt (kg)].

MAIN OUTCOME MEASURE

Correct ETT position, that is, between the upper border of T1 and lower border of T2 on CXR, determined by one consultant paediatric radiologist masked to group assignment.

RESULTS

There was no difference in the proportion of correctly placed ETT tips between the groups (suprasternal palpation 27/58 (47%) vs weight 23/60 (38%), p=0.456). Most incorrectly positioned ETTs were too low (56/68 (82%)).

CONCLUSION

Estimating ETT insertion depth using suprasternal palpation did not result in more correctly positioned ETTs.

TRIAL REGISTRATION NUMBER

ISRCTN13570106.

Comparisons and Refinements of Neonatal Oro-Tracheal Intubation Length Estimation Methods in Taiwanese Neonates

Objective: This study aimed to evaluate the efficacy of Tochen's formula [TF, body weight (kg) plus 6 cm], nasal septum to ear tragus length (NTL) + 1 cm, and Neonatal Resuscitation Program gestational age (NRP-GA) and body weight (NRP-BW)-based intubation table in estimating the oro-tracheal intubation length, and to improve the estimation efficacy using anthropometric measurements in Taiwanese neonates. Study design: This was a prospective observational study conducted at a neonatal intensive care unit in Taipei, Taiwan. One hundred intubated neonates were enrolled. The estimated intubation depth was defined as being mid-tracheal concordant if it placed the endotracheal tip between the upper border of the first and the lower border of the second thoracic vertebra. A linear regression model was used to analyze the relationships between mid-tracheal depth and body weight (BW), NTL and gestational age (GA), and to revise the NRP intubation tables using our results. Results: Overall, 56% of the neonates were born at a GA ≤ 28 weeks and 48% had a BW ≤ 1,000 g. The overall mid-tracheal concordance rates for TF, NTL + 1 cm, NRP-GA, and NRP-BW estimations were 51.0, 57.0, 15.0, and 14.0%, and in the infants with a BW ≤ 1,000 g 56.3, 56.3, 8.3, and 8.3%, respectively. Our revisions of the NRP intubation tables based on the anthropometric measurements of our participants improved the efficacy of BW, GA, and NTL estimations to 63, 44, and 61%, respectively. Conclusion: TF and NTL + 1 cm were more reliable than NRP intubation tables in predicting the neonatal mid-tracheal length in neonates of all BW and GA. Considering morphological differences secondary to ethnicity, we recommend using these tailored recommendations during neonatal resuscitation in Asian neonates.

A novel training simulator for portable ultrasound identification of incorrect newborn endotracheal tube placement - observational diagnostic accuracy study protocol

Background

Endotracheal tube (ETT) placement is a critical procedure for newborns that are unable to breathe. Inadvertent esophageal intubation can lead to oxygen deprivation and consequent permanent neurological impairment. Current standard-of-care methods to confirm ETT placement in neonates (auscultation, colorimetric capnography, and chest x-ray) are time consuming or unreliable, especially in the stressful resuscitation environment. Point-of-care ultrasound (POCUS) of the neck has recently emerged as a powerful tool for detecting esophageal ETTs. It is accurate and fast, and is also easy to learn and perform, especially on children.

Methods

This will be an observational diagnostic accuracy study consisting of two phases and conducted at the Aga Khan University Hospital in Karachi, Pakistan. In phase 1, neonatal health care providers that currently perform standard-of-care methods for ETT localization, regardless of experience in portable ultrasound, will undergo a two-hour training session. During this session, providers will learn to detect tracheal vs. esophageal ETTs using POCUS. The session will consist of a didactic component, hands-on training with a novel intubation ultrasound simulator, and practice with stable, ventilated newborns. At the end of the session, the providers will undergo an objective structured assessment of technical skills, as well as an evaluation of their ability to differentiate between tracheal and esophageal endotracheal tubes. In phase 2, newborns requiring intubation will be assessed for ETT location via POCUS, at the same time as standard-of-care methods. The initial 2 months of phase 2 will include a quality assurance component to ensure the POCUS accuracy of trained providers. The primary outcome of the study is to determine the accuracy of neck POCUS for ETT location when performed by neonatal providers with focused POCUS training, and the secondary outcome is to determine whether neck POCUS is faster than standard-of-care methods.

Discussion

This study represents the first large investigation of the benefits of POCUS for ETT confirmation in the sickest newborns undergoing intubations for respiratory support.

Trial registration

ClinicalTrials.gov Identifier: NCT03533218. Registered May 2018.

Determination of optimal endotracheal tube tip depth from the gum in neonates by X-ray and ultrasound

Background/objective: Proper placement of endotracheal tube (ETT) in the midtrachea is essential. Initial depth of placement of oral ETT from the lips is commonly estimated based on weight ("7-8-9 rule"), gestational age, or nasal-tragus distance. However, these measurements can be altered by superficial factors and the mobility of the lips relative to the airway, so the upper alveolar ridge (gum) may provide a superior landmark. Also, confirmation of ETT tip position by point of care ultrasound (POC-US) is noninvasive and may enable localization of the ETT tip in real time. The objective of this study is to define optimal initial ETT depth from the gum in infants relative to weight, and to compare the efficacy of POC-US with standard chest X-ray (CXR) for confirming ETT tip position.Methods: Neonates requiring oral intubation were enrolled. At the time of CXR that were obtained for clinical indications, the position of the ETT at both the lip and gum were recorded. "Optimal" ETT placement in midtrachea (from lip and gum) was calculated based on the observed measurements and the distance of the ETT tip from the carina on CXR. Linear regression was used to model ideal placement of ETT, as a function of weight. POC-US was performed using a 10 MHz cardiac probe and high parasternal view. Distance from the ETT bevel to the superior aspect of the right pulmonary artery, which is at the level of carina, was measured using electronic calipers.Results: Infants were recruited at a median age of 3 days (n = 75), weight 1300 g, and corrected gestational age 31.6 ± 5.8 weeks. The regression equation for optimal placement from the gum (in cm) was 5.21 + 1.03 × weight (kg). Using estimates of 5 or 5.5 cm + weight (kg) to the gum yielded accuracy similar or superior to the 7-8-9 rule to the lip. Most of the variability in ideal placement of ETT tip from the gum was determined by weight (R2 = 0.83). The difference between optimal placement using lip and gum was 0.51 ± 0.24 cm. ETT location by POC-US (n = 40) was in substantial agreement with CXR (intraclass correlation coefficient 0.95, 95% CI: 0.92, 0.98).Conclusions: Marking oral ETT placement to the gum is feasible, with optimal depth of about 5.2 cm + weight (kg), across all weight categories. POC-US can be used for rapid confirmation of continued ideal ETT tip location, with accuracy similar to CXR. Further studies will be needed to determine whether marking ETT depth to the gum or using POC-US achieves the goal of decreased complications of ETT misplacement or displacement.

Development of a novel reference nomogram for endotracheal intubation in neonatal emergency transport setting

AIM

Neonatal endotracheal intubation is a challenging procedure during transport. The aim of this study was to evaluate the effectiveness of the emergency intubation guidelines followed by our Neonatal Emergency Transport Service (NETS).

METHODS

Our transport intubation guidelines follows a weight-based nomogram for nasal intubation, and the tube position is clinically verified after intubation, while the postintubation chest X-ray is postponed to Neonatal Intensive Care Unit (NICU) admission. Data on postnatal age, weight and tube insertion depth were obtained from the online NETS clinical database, and the postintubation chest X-ray images were assessed.

RESULTS

During the study period, 161 newborn infants were nasally intubated during transport, and received a postintubation radiograph at NICU admission. A total of 130 neonates (80.7%) had the endotracheal tube (ETT) correctly positioned between T1 and T2 vertebrae, while 12 (7.5%) was at C7 vertebrae level and 19 (11.8%) at T3. No patients had ETT tip positioned at T4 vertebrae level or below. No adverse events related to intubation were observed.

CONCLUSION

Our intubation procedure showed a good reliability and safety in neonatal critical care transport, although chest X-ray to confirm the tube placement is postponed to NICU arrival. Based on our results, we suggest a revised version of weight-based nomogram for nasal intubation.

The Oro-Helical Length Accurately Predicts Endotracheal Tube Insertion Depth in Neonates

We evaluated the reliability of the oro-helical length in predicting the ideal endotracheal tube depth in neonates and found the oro-helical length was a consistently more reliable and better predictor of the ideal endotracheal tube depth on chest radiograph than the 7-8-9 rule, especially in infants weighing ≤1500 g.

Respiratory Care for the Ventilated Neonate

Invasive ventilation is often necessary for the treatment of newborn infants with respiratory insufficiency. The neonatal patient has unique physiological characteristics such as small airway caliber, few collateral airways, compliant chest wall, poor airway stability, and low functional residual capacity. Pathologies affecting the newborn's lung are also different from many others observed later in life. Several different ventilation modes and strategies are available to optimize mechanical ventilation and to prevent ventilator-induced lung injury. Important aspects to be considered in ventilating neonates include the use of correct sized endotracheal tube to minimize airway resistance and work of breathing, positioning of the patient, the nursing care, respiratory kinesiotherapy, sedation and analgesia, and infection prevention, namely, the ventilator-associated pneumonia and nosocomial infection, as well as prevention and treatment of complications such as air leaks and pulmonary hemorrhage. Aspects of ventilation in patients under ECMO (extracorporeal membrane oxygenation) and in palliative care are of increasing interest nowadays. Online pulmonary mechanics and function testing as well as capnography are becoming more commonly used. Echocardiography is now a routine in most neonatal units. Near infrared spectroscopy (NIRS) is an attractive tool potentially helping in preventing intraventricular hemorrhage and periventricular leukomalacia. Lung ultrasound is an emerging tool of diagnosis and can be of added value in helping monitoring the ventilated neonate. The aim of this scientific literature review is to address relevant aspects concerning the respiratory care and monitoring of the invasively ventilated newborn in order to help physicians to optimize the efficacy of care.

WITHDRAWN: Techniques to ascertain correct endotracheal tube placement in neonates

BACKGROUND

The success rate of correct endotracheal tube (ETT) placement for junior medical staff is less than 50% and accidental oesophageal intubation is common. Rapid confirmation of correct tube placement is important because tube malposition is associated with serious adverse outcomes including hypoxaemia, death, pneumothorax and right upper lobe collapse.ETT position can be confirmed using chest radiography, but this is often delayed; hence, a number of rapid point-of-care methods to confirm correct tube placement have been developed. Current neonatal resuscitation guidelines advise that correct ETT placement should be confirmed by the observation of clinical signs and the detection of exhaled carbon dioxide (CO2). Even though these devices are frequently used in the delivery room to assess tube placement, they can display false-negative results. Recently, newer techniques to assess correct tube placement have emerged (e.g. respiratory function monitor), which have been claimed to be superior in the assessment of tube placement.

OBJECTIVES

To assess various techniques for the identification of correct ETT placement after oral or nasal intubation in newborn infants in either the delivery room or neonatal intensive care unit compared with chest radiography.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL,The Cochrane Library 2012, Issue 4), MEDLINE (January 1996 to June 2014), EMBASE (January 1980 to Juen 2014) and CINAHL (January 1982 to June 2014). We searched clinical trials registers and the abstracts of the Society for Pediatric Research and the European Society for Pediatric Research from 2004 to 2014. We did not apply any language restrictions.

SELECTION CRITERIA

We planned to include randomised and quasi-randomised controlled trials and cluster trials that compared chest radiography with clinical signs, respiratory function monitors, exhaled CO2 detectors or ultrasound for the assessment of correct ETT placement either in the delivery room or the neonatal intensive care unit.

DATA COLLECTION AND ANALYSIS

Two review authors independently evaluated the search results against the selection criteria. We did not perform data extraction and 'Risk of bias' assessments because we identified no studies that met our inclusion criteria.

MAIN RESULTS

We did not identify any studies meeting the criteria for inclusion in this review.

AUTHORS' CONCLUSIONS

There is insufficient evidence to determine the most effective technique for the assessment of correct ETT placement either in the delivery room or the neonatal intensive care unit. Randomised clinical trials comparing either of these techniques with chest radiography are warranted.

Randomised trial of estimating oral endotracheal tube insertion depth in newborns using weight or vocal cord guide

BACKGROUND

When intubating newborns, clinicians aim to position the endotracheal tube (ETT) tip in the midtrachea. The depth to which ETTs should be inserted is often estimated using the infant's weight. ETTs are frequently incorrectly positioned in newborns, most often inserted too far. Using the vocal cord guide (a mark at the distal end of the ETT) to guide insertion depth has been recommended.

OBJECTIVE

To determine whether estimating ETT insertion depth using the vocal cord guide rather than weight results in more correctly positioned ETT tips.

DESIGN

Single-centre randomised controlled trial.

SETTING

Level III neonatal intensive care unit (NICU) at a university maternity hospital (National Maternity Hospital, Dublin, Ireland).

PATIENTS

Newborn infants without congenital anomalies intubated in the NICU.

INTERVENTIONS

Participants were randomised to have ETT insertion depth estimated using weight [insertion depth (cm) = weight (kg) +6] or vocal cord guide.

MAIN OUTCOME MEASURE

Correct ETT position, that is, tip between the upper border of the first thoracic vertebra (T1) and the lower border of the second thoracic vertebra (T2) on a chest X-ray as determined by one paediatric radiologist masked to group assignment.

RESULTS

136 participants were randomised. The proportion of correctly positioned ETTs was similar in both groups (weight 30/69 (44%) vs vocal cord guide 27/67 (40%), p=0.731). Most incorrectly positioned ETT (69/79, 87%) were too low.

CONCLUSION

Estimating ETT insertion depth using the vocal cord guide did not result in more correctly positioned ETT tips.

TRIAL REGISTRATION NUMBER

ISRCTN39654846.

Reexamining the ideal depth of endotracheal tube in neonates

BACKGROUND

The appropriate endotracheal tube (ET) depth for the newborn with respiratory failure is important. Inappropriate ET depth increases the risk of uneven lung expansion and collapse. This retrospective study aimed to compare the final ideal ET depth with Tochen's formula in Taiwanese intubated neonates, and to determine the correlation between neonatal factors and final ideal ET depth, and to devise an accurate predictive formula for use in Taiwan.

METHODS

Data were collected from neonates who required endotracheal intubation and who were admitted to the Neonatal Intensive Care Unit from 2011 to 2015. Correlations between the final ideal ET depth, GA, and BW were assessed using the Pearson correlation test. Multiple regression analysis was used to produce a formula to predict appropriate ET depth from mouth angle to midtracheal position of neonates.

RESULTS

A total of 139 neonates were enrolled in this study. The final ideal ET depth was in concordance with Tochen's formula only in 19 neonates (13.7%); relatively deeper in 30 (21.6%) neonates; and shallower than the values from Tochen's formula in 90 (64.7%) neonates. Multiple regression analysis showed that the BW and GA together produced best prediction for final ideal ET depth in our study population. SGA and gender were shown to be insignificantly related to final ideal ET depth.

CONCLUSION

Our study showed the final ideal ET depth was shallower than Tochen's formula in 64.7% of neonates. Tochen's formula might not be suitable to predict ET depth for neonates in Taiwan. In our study, the new formula: 4.0 + 1.0 BW (kg) + 0.05 GA (weeks) provides a more accurate value and alternative method for evaluating the final ideal ET depth in Taiwan. A practical guideline for Asian neonates should be validated by prospective studies with large sample sizes.

Efficacy of modified Tochen's formula for optimum endotracheal tube placement in low birth weight neonates: an RCT

OBJECTIVE

To assess the efficacy of modified Tochen's formula (birth weight + 5 cm) when compared to Tochen's formula for optimum placement of endotracheal tubes (ET) in low birth weight (LBW) neonates.

STUDY DESIGN

In the NICU of a tertiary care hospital, LBW babies requiring intubation were randomized to Tochen's formula or modified Tochen's formula. The incidence of inadequate placement and optimum length of ET insertion were estimated. Analysis was done by the Chi square and 't'-tests.

RESULTS

Sixty-seven babies were included: 34 in Tochen's group and 33 in modified Tochen's group. Baseline characteristics were similar. Modified Tochen's formula was significantly (p = 0.006) closer to the optimum position when compared to Tochen's formula. The percentages of optimum and adequate placements of the ET tube was higher in the modified Tochen's group, though not statistically significant.

CONCLUSION

Modified Tochen's formula in LBW babies may enable more optimum placement of ETs.

Optimal Insertion Depth for Endotracheal Tubes in Extremely Low-Birth-Weight Infants

OBJECTIVE

To determine the optimal endotracheal tube insertion depth in extremely low-birth-weight infants based on the association between endotracheal tube depth and gestational age, body weight, body length, and head and chest circumferences at birth.

DESIGN

Retrospective chart review.

SETTING

Neonatal ICU at a medical center.

PATIENTS

Fifty-two hospitalized extremely low-birth-weight infants in our neonatal ICU.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Data regarding gestational age, body weight, body length (crown-heel length), head and chest circumferences, and final endotracheal tube depth were retrieved from the medical records of 52 newborn infants weighing less than or equal to 1,000 g at birth (boys, 29; girls, 23). The mean gestational age was 25.1 (range, 22-32) weeks, and the mean body weight was 724.5 (range, 400-1,000) g. Of the endotracheal tubes used, 3%, 87%, and 10% of endotracheal tubes were of size 2.0, 2.5, and 3.0, respectively. Linear regression analysis revealed a significant association between endotracheal tube depth and gestational age, body weight, body length, head, and chest circumferences (p < 0.001). Body weight had the highest coefficient of determination (r = 0.497), followed by body length (0.458), with all other variables having values of less than 0.4.

CONCLUSIONS

In extremely low-birth-weight infants, a linear association exists between endotracheal tube insertion depth and gestational age, body weight, body length, chest, and head circumferences at birth. Although body weight is the most accurate method for predicting endotracheal tube insertion depth, body length is also appropriate and is more favorable than body weight in delivery room resuscitation. Although no substitute for radiologic confirmation exists, a tape measure that can convert body length to endotracheal tube depth may be helpful.

Pulmonary atelectasis in newborns with clinically treatable diseases who are on mechanical ventilation: clinical and radiological aspects

Objective

To analyze the radiological aspects of pulmonary atelectasis in newborns on mechanical ventilation and treated in an intensive care unit, associating the characteristics of atelectasis with the positioning of the head and endotracheal tube seen on the chest X-ray, as well as with the clinical variables.

Materials and Methods

This was a retrospective cross-sectional study of 60 newborns treated between 1985 and 2015. Data were collected from medical records and radiology reports. To identify associations between variables, we used Fisher's exact test. The level of significance was set at p < 0.05.

Results

The clinical characteristics associated with improper positioning of the endotracheal tube were prematurity and a birth weight of less than 1000 g. Among the newborns evaluated, the most common comorbidity was hyaline membrane disease. Atelectasis was seen most frequently in the right upper lobe, although cases of total atelectasis were more common in the left lung. Malpositioning of the head showed a trend toward an association with atelectasis in the left upper lobe.

Conclusion

Pulmonary atelectasis is a common complication in newborns on mechanical ventilation. Radiological evaluation of the endotracheal tube placement provides relevant information for the early correction of this condition.

Optimal Line and Tube Placement in Very Preterm Neonates: An Audit of Practice

BACKGROUND

Placement of endotracheal tubes (ETTs) and umbilical catheters (UCs) is essential in very preterm infant care. The aim of this study was to assess the effect of an educational initiative to optimize correct placement of ETTs and UCs in very preterm infants.

METHODS

A pre-post study design, evaluating optimal radiological position of ETTs and UCs in the first 72 h of life in infants <32 weeks gestational age (GA) was performed. Baseline data was obtained from a preceding 34-month period. The study intervention consisted of information from the pre-intervention audit, surface anatomy images of the newborn for optimal UC positioning, and weight-based calculations to estimate insertion depths for endotracheal intubation. A prospective evaluation of radiological placement of ETTs and UCs was then conducted over a 12-month period.

RESULTS

During the study period, 211 infants had at least one of the three procedures performed. One hundred and fifty-seven infants were included in the pre-education group, and 54 in the post-education group. All three procedures were performed in 50.3% (79/157) in the pre-education group, and 55.6% (30/54) in the post-education group. There was no significant difference in accurate placement following the introduction of the educational sessions; depth of ETTs (50% vs. 47%), umbilical arterial catheter (UAC) (40% vs. 43%,), and umbilical venous catheter (UVC)(14% vs. 23%).

CONCLUSION

Despite education of staff on methods for appropriate ETT, UVC and UAC insertion length, the rate of accurate initial insertion depth remained suboptimal. Newer methods of determining optimal position need to be evaluated.

Accuracy of the nasal-tragus length measurement for correct endotracheal tube placement in a cohort of neonatal resuscitation simulators

OBJECTIVE

Nasal-tragus length (NTL) estimates of endotracheal tube (ETT) depth are replacing weight-based estimates for endotracheal tube depth in neonates requiring endotracheal intubation. Existing neonatal simulators were designed before interest in using the NTL, and may lack fidelity in this measurement. The objective of this study is to evaluate the accuracy of the adjusted NTL formula and the Neonatal Resuscitation Program (NRP) gestational age/weight-based ETT depth chart in predicting proper endotracheal tube insertion depth in a cohort of neonatal simulators.

STUDY DESIGN

The NTL and appropriate intubation depth to the mid-trachea were measured for 11 commonly used neonatal intubation simulators.

RESULTS

The NTL+1 cm formula incorrectly estimates the mid-tracheal depth in 82% of simulators, and the weight-based chart incorrectly estimates depth in 75% of test simulators. Only one simulator experienced a mainstem intubation with ETT insertion to the depth predicted by the NTL+1 cm formula.

CONCLUSIONS

The majority of neonatal resuscitation simulations lacked physical fidelity with regard to mid-tracheal ETT insertion depth. The NRP gestational age/weight-based chart outperformed the NTL+1 cm formula but still resulted in endotracheal tube misplacement in the majority of neonatal simulators. The majority of simulators had adequate functional fidelity using either method for ETT depth estimation.

Rigid catheters reduced duration of less invasive surfactant therapy procedures in manikins

AIM

Different catheters can be used for less invasive surfactant therapy (LIST): feeding tubes inserted with or without Magill forceps, different angiocatheters and centre specific devices, such as umbilical catheters affixed to a stylet. This study compared the effectiveness of LIST devices and endotracheal tubes (ETT).

METHODS

Video recordings of 20 neonatologists simulating different LIST techniques on two manikin heads were analysed. Procedural effectiveness was evaluated by the duration of procedures and failure rates. Ease of use was scored.

RESULTS

The median procedure time for the Neonatal Intubation Trainer was significantly longer with feeding tubes without Magill forceps. For the more difficult ALS Baby Trainer, successful procedures lasted a median of 24 (17-32) seconds with ETT, 24 (15-36) seconds with stylet-guided catheters and 34 (27-46) seconds and 37 (29-42) seconds with 13-cm and 30-cm angiocatheters, respectively. Both methods using feeding tubes were statistically slower than ETT intubation, lasting 32 (25-44) seconds and 39 (27-95) seconds with or without Magill forceps. Failure rates (7-20%) were no different between the LIST methods. Techniques using feeding tubes were rated as more difficult.

CONCLUSION

Only rigid or stylet-guided catheters required tracheal catheterisation times similar to those of endotracheal intubation and neonatologists found them easier.

Three-Dimensional Imaging-Based Web Application for Predicting Tracheal Tube Depth in Preterm Neonates

BACKGROUND

Positioning a tracheal tube (TT) to the correct depth in preterm infants is challenging. Currently, there is no reliable single-predictor model for neonates applicable to the whole range of size or age.

OBJECTIVE

In this study, we used post-mortem magnetic resonance imaging (PMMRI) of preterm infants to measure tracheal dimensions and to develop a clinical guide for TT positioning.

METHODS

We measured tracheal length (TL) and tracheal diameter (TD) in a cohort of normal neonates and foetuses that underwent PMMRI (cause of death unexplained). The distance between the lips and the mid-tracheal point, i.e., the mid-tracheal length (mid-TL), and the TD measurement were obtained. We produced univariate prediction models of mid-TL and TD, using gestational age (GA), foot length (FL), crown-rump length (CRL) and body weight (BW) as potential predictors, as well as multiple prediction models for mid-TL.

RESULTS

Tracheal measurements were performed in 117 cases, with a mean GA of 28.8 weeks (range 14-42 weeks). The best linear association was between mid-TL and FL (mid-TL = FL × 0.914 + 1.859; R2 = 0.94), but was improved by multivariate regression models. We developed a prediction tool using only GA and BW (R2 = 0.92), and all four predictors (GA, BW, FL and CRL; R2 = 0.94) which is now available as a web-based application via the Internet.

CONCLUSION

Post-mortem imaging data provide estimates of TT insertion depth. Our prediction tool based on age and BW can be used at the bedside and is ready to be tested in clinical practice.

Prediction of the midtracheal level based on external anatomical landmarks: implication of the optimal insertion depth of endotracheal tubes in pediatric patients

BACKGROUND

Optimal positioning of endotracheal tubes (ETTs) decreases the risk of accidental extubation or endobronchial intubation. This study evaluated the usefulness of external anatomical landmarks as practical references for determining an insertion depth of an ETT in pediatric patients.

METHODS

Computed tomography images of the necks of 183 pediatric patients (≤16 years of age) were reviewed. Levels corresponding to the vocal cords, cricoid cartilage, suprasternal notch, manubriosternal junction, and carina were identified on sagittal reconstructed images. The surface measurements from the cricoid cartilage to the suprasternal notch and that from the suprasternal notch to the manubriosternal junction were determined. Bland-Altman analysis was used to interpret the relationship between the midtracheal level and the surface measurements.

RESULTS

The difference between the midtracheal level and the surface distance from the cricoid cartilage to the suprasternal notch was 3.5 ± 7.0 mm, which was closer to zero than that between the midtracheal level and the surface distance from the suprasternal notch to the manubriosternal junction of 15.1 ± 6.1 mm.

CONCLUSION

The midtracheal level, helpful in planning the insertion depth of an ETT, can be predicted by measuring the surface distance from the cricoid cartilage to suprasternal notch in pediatric patients.

Is It Time to Review Guidelines for ETT Positioning in the NICU? SCEPTIC-Survey of Challenges Encountered in Placement of Endotracheal Tubes in Canadian NICUs

Objectives. To examine current opinions and practices regarding endotracheal tube placement across several Canadian Neonatal Intensive Care Units. Design. Clinical directors from Canadian Neonatal Network affiliated NICUs and Neonatal-Perinatal Programs across Canada were invited via email to participate in and disseminate the online survey to staff neonatologists, neonatal fellows, respiratory therapists, and nurse practitioners. Result. There is wide variability in the beliefs and practices related to ETT placement. The majority use “weight +6” formula and “aim to black line” on ETT at vocal cords to estimate the depth of an oral ETT and reported estimation as challenging in ELBW infants. The majority agreed that mid-trachea is an ideal ETT tip position; however their preferred position on chest X-ray varied. Many believe that ETT positioning could be improved with more precise ETT markings. Conclusion. Further research should focus on developing more effective guidelines for ETT tip placement in the ELBW infants.

Evaluation of body parameters for estimation of endotracheal tube length in Indian neonates

The objectives were to estimate the incidence of inadequate placement of the endotracheal tube (ET) using Tochen's formula (6 + birth weight) and to correlate optimum ET length with anthropometric measurements in neonates. A cross-sectional analytical study was conducted in 50 neonates. Neonates requiring intubation for ventilation, with a confirmatory chest radiograph, were intubated using Tochen's formula, after which tube placement was verified by auscultation. The incidence of inadequate placement and optimum length of ET insertion were estimated from chest radiographs. Anthropometric parameters were measured and correlated with the optimum length and regression equations generated. The incidence of inadequate placement of the ET was 40 % (20 of 50). The incidence of inadequate placement was higher (5 of 6, 83 %) in extremely low birth weight (ELBW) infants, and in extreme preterm infants (5 of 5, 100 %). It was found that all the anthropometric parameters correlated well (r between 0.71 and 0.84) with the optimum ET length.

CONCLUSION

The incidence of inadequate placement was high, especially in the ELBWs' and extreme preterm infants. Birth weight, sternal length, and shoulder umbilical length correlated significantly with optimum ET length and may guide optimal ET placement.

Monitoring tidal volumes in preterm infants at birth: mask versus endotracheal ventilation

OBJECTIVE

Upper airway distention during mask ventilation could reduce gas volumes entering the lung compared with ventilation via an endotracheal tube. Therefore, respiratory tract volumes were measured in lambs and tidal volumes were compared in preterm infants before and after intubation.

DESIGN

In seven preterm lambs, volumes of the airways (oropharynx, trachea, lungs) were assessed. In 10 preterm infants, delta pressures, tidal volumes and leak were measured during ventilation 2 min before (mask ventilation) and 2 min after intubation (endotracheal ventilation). Inflations coinciding with breaths were excluded.

OUTCOME MEASURES

Amount of upper airway distention in lambs and differences in inspiratory and expiratory tidal volume before and after intubation.

RESULTS

In lambs, the combined trachea and oropharynx contributed to 14 (12-21) % (median (IQR), whereas the oropharynx contributed to 9 (7-10) % of the total tidal volume measured at the mouth. In preterm infants, inspiratory (11.1 (7.9-22.6) mL/kg vs 5.8 (3.9-9.6) mL/kg (p=0.01)) and expiratory (8.3 (6.8-15.4) mL/kg vs 4.9 (3.9-9.6) mL/kg (p=0.02)) tidal volumes were significantly larger during mask ventilation compared with endotracheal ventilation. Leak was 18.7 (3.3-28.7) % before versus 0 (0-2.3) % after intubation (p<0.0001). Delta pressure was 23.7 (20.8-25.6) cm H2O before versus 24.8 (20.8-26.0) cm H2O after intubation (p>0.05). During mask ventilation, expiratory tidal volume increased from 10.0 (5.4-15.6) mL/kg to 11.3 (7.6-17.0) mL/kg (p=0.01), but remained unchanged during endotracheal ventilation.

CONCLUSIONS

During neonatal mask ventilation, distention of the upper respiratory tract contributes to the tidal volumes measured and should be taken into account when targeting tidal volumes during mask ventilation.

Automated detection of endotracheal tubes in paediatric chest radiographs

The aim of this study was to develop an automated method for the detection of endotracheal tube and location of its tip in paediatric chest radiographs. In this method, a seed point was first determined from the line crossing the cervical region and a line path was traced from the seed point. Two features, Lmax and C, were determined from the path and were combined to detect the existence of the endotracheal tube. Multiple thresholds applied to the line path were used to determine the candidate locations for the tip, and the most suitable location was selected from these candidates by analysing the image features. To evaluate the performance of detection of endotracheal tube existence, support vector machine was used to classify the images with and without endotracheal tubes on the basis of Lmax and C. The discriminant performance of the method was evaluated using receiver operating characteristic (ROC) analysis. To evaluate the precision of the detected tip locations, the tip locations in paediatric chest images were annotated by a radiologist. The distance (error) between the detected and annotated locations was used to evaluate detection precision for the tip location. The proposed method was evaluated using 528 images with endotracheal tubes and 816 images without endotracheal tubes. The discriminant performance in this study, evaluated as Az (area under the ROC curve), for detecting the existence of endotracheal tubes on the basis of the two features was 0.943±0.009, and the detection error of the tip location was 1.89±2.01mm. The proposed method obtained high performance results and could be useful for detecting the malposition of endotracheal tubes in paediatric chest radiographs.

Estimating the endotracheal tube insertion depth in newborns using weight or gestation: a randomised trial

BACKGROUND

When intubating newborns, clinicians aim to place the tip of the endotracheal tube (ETT) in the mid-trachea. Clinicians usually estimate the ETT insertion depth based on weight. ETT tips are often incorrectly positioned in newborns. Estimating the insertion depth based on gestation may be more accurate.

OBJECTIVE

To determine whether estimating the ETT insertion depth using gestation, compared to weight, results in more correctly placed ETTs.

METHODS

Newborn infants without congenital anomalies who were intubated orally were randomised to having their ETT insertion depth estimated using weight [insertion depth (cm) = weight (kg) + 6] or gestation [value determined from a table]. The primary outcome was correct ETT position, defined as an ETT tip between the upper border of the first thoracic vertebra (T1) and the lower border of the second thoracic vertebra (T2) on a chest X-ray. The primary outcome was determined by one paediatric radiologist who was masked to group assignment.

RESULTS

Ninety infants were enrolled and the groups were well matched. The proportion of correctly placed ETTs was not significantly different between the groups [weight, 25/49 (51%), vs. gestation, 16/41 (39%), p = 0.293]. We found no significant differences in the secondary outcomes measured.

CONCLUSION

Estimating the ETT insertion depth in newborns using gestation compared to weight did not result in more correctly placed ETTs.

Phthalates and critically ill neonates: device-related exposures and non-endocrine toxic risks

OBJECTIVE

To assess the types and magnitudes of non-endocrine toxic risks to neonates associated with medical device-related exposures to di(2-ethylhexyl)phthalate (DEHP).

STUDY DESIGN

Dose-response thresholds for DEHP toxicities were determined from published data, as were the magnitudes of DEHP exposures resulting from neonatal contact with polyvinyl chloride (PVC) devices. Standard methods of risk assessment were used to determine safe levels of DEHP exposure in neonates, and hazard quotients were calculated for devices individually and in aggregate.

RESULT

Daily intake of DEHP for critically ill preterm infants can reach 16 mg/kg per day, which is on the order of 4000 and 160,000 times higher than desired to avoid reproductive and hepatic toxicities, respectively. The non-endocrine toxicities of DEHP are similar to complications experienced by preterm neonates.

CONCLUSION

DEHP exposures in neonatal intensive care are much higher than estimated safe limits, and might contribute to common early and chronic complications of prematurity. Concerns about phthalates should be expanded beyond endocrine disruption.