Normative Data of Optimally Placed Endotracheal Tube by Point-of-care Ultrasound in Neonates

Point-of-Care Ultrasound for the Tip of the Endotracheal Tube: A Neonatologist Perspective

OBJECTIVE

 Point-of-care ultrasound (POCUS) has been reported to reduce radiation exposure and has been shown to be a reliable bedside technique to confirm endotracheal tube (ETT) placement, but evidence in neonates is still limited. The aim of this study was to compare the effectiveness and reliability of POCUS performed by a neonatologist, as an alternative to chest radiography (CXR) for the optimal position of ETT.

STUDY DESIGN

 Newborns who underwent intubation were included in this prospective observational study. The CXR was used to evaluate the position of the ETT tip and categorized into three groups: above the T1, between the T1 and T3, and below the T3 vertebra. An experienced neonatologist measured the distance between the ETT tip and the upper border of the aortic arch from the suprasternal notch with ultrasonography (US). A 5 to 10 mm measurement was considered as the optimal distance, and the position was classified into three categories: correct, high, and deep.

RESULTS

 Among 91 measurements performed on 63 intubated patients with US, 73 (80%) were within the 5 to 10 mm range (correct position). Of these, 61 (92.4%) were determined to be between T1 and 3 vertebrae in CXR. There was no significant difference between the two methods, and the US had an excellent ability to distinguish the correct position of the ETT. The distance measured by the US for the ETT tip to be located between the T1 and T3 vertebrae on CXR should range between 6.17 and 9.0 mm.

CONCLUSION

 This study showed that the US by an experienced neonatologist is an easy and feasible alternative to determine the position of the ETT in the neonatal intensive care unit.

KEY POINTS

· POCUS has been reported to reduce radiation exposure, and it is areliable bedside technique.. · Evidence for confirmation of ETT placement in neonates is limited.. · POCUS can be used for determination of ETT position in NICU's by experienced neonatologists..

Ultrasound assessment of endotracheal tube depth in neonates: a prospective feasibility study

OBJECTIVE

To examine the reliability of a novel ultrasound (US) method for assessment of endotracheal tube (ETT) position in neonates.

DESIGN

Prospective, observational, single-centre, feasibility study.

SETTING

Level III neonatal intensive care unit.

PATIENTS

Term and preterm neonates requiring endotracheal intubation.

INTERVENTION

US measurement of the ETT tip to right pulmonary artery (RPA) distance was used to determine ETT position according to one-fourth to three-fourths estimated tracheal length for weight. US demonstration of pleural sliding and diaphragmatic movement was also assessed. Chest radiography (CXR) was performed following each intubation.

MAIN OUTCOME MEASURES

Agreement between US assessment of ETT tip position and CXR served as the gold standard. Sensitivity, specificity, positive and negative predictive values for each US method and correlation between ETT tip to RPA distance on US, and ETT tip to carina distance on CXR were assessed.

RESULTS

Forty-two US studies were performed on 33 intubated neonates. US evaluation of ETT-RPA distance identified 100% of ETTs positioned correctly: 77% deep and 80% high, demonstrating strong agreement with CXR (kappa=0.822). Sensitivity was 78%, specificity 100%, positive predictive value 100% and negative predictive value 86%. US ETT-RPA distance strongly correlated with CXR ETT-carina distance (r=0.826). No significant agreement was found between CXR and US assessment of pleural sliding and diaphragmatic movement. No adverse events were encountered during US scans.

CONCLUSION

US evaluation of ETT-RPA distance demonstrated excellent accuracy for determining ETT position in neonates compared with CXR. More research is needed to support its feasibility in clinical settings.

Authors' Reply on: FOCUS more on POCUS

How to cite this article: Subramani S, Parameswaran N. Authors' Reply on: FOCUS more on POCUS. Indian J Crit Care Med 2023;27(3):226-227.

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.

[Evaluation of the Endotracheal Tube by Ultrasound in Neonates]

The reliable evaluation of a correctly placed endotracheal tube is an essential challenge in neonatology. Point-of-care ultrasound is an emerging method to address this concern with the following advantages: less time-consuming, no exposure to radiation, less staff-intensive, and high tolerability by the patients. This article focuses on the evaluation of the clinical application of point-of-care ultrasound to examine the position of the endotracheal tube with regard to visualization, consistency compared to the chest X-ray, and the level of training to obtain sufficient results. We identified nine studies relevant to these questions. The visualization of the endotracheal tube by using point-of-care ultrasound is highly effective. The assessment of a correctly placed endotracheal tube is comparable to the results of a chest X-ray. The technique is suitable for any examiner with previous ultrasound experience. Future applications such as emergency intubations, implementation in the standard care of extremely low birth weight preterm babies, and use in low-resource settings could be promising. This article offers a practical guideline to promote the level of awareness and the clinical application.

Sonographic Evaluation of the Endotracheal Tube Position in the Neonatal Population: A Comprehensive Review and Meta-Analysis

BACKGROUND

Endotracheal intubation in neonates is challenging and requires a high level of precision, due to narrow and short airways, especially in preterm newborns. The current gold standard for endotracheal tube (ETT) verification is chest X-ray (CXR); however, this method presents some limitations, such as ionizing radiation exposure and delayed in obtaining the radiographic images, that point of care ultrasound (POCUS) could overcome.

PRIMARY OBJECTIVE

To evaluate ultrasound efficacy in determining ETT placement adequacy in preterm and term newborns.

SECONDARY OBJECTIVE

To compare the time required for ultrasound confirmation vs. time needed for other standard of care methods.

SEARCH METHODS

A search in Medline, PubMed, Google Scholar and in the Cochrane Central Register of Controlled Trials (CENTRAL) was performed. Our most recent search was conducted in September 2021 including the following keywords: "newborn", "infant", "neonate", "endotracheal intubation", "endotracheal tube", "ultrasonography", "ultrasound".

SELECTION CRITERIA

We considered randomized and non-randomized controlled trials, prospective, retrospective and cross-sectional studies published after 2012, involving neonatal intensive care unit (NICU) patients needing intubation/intubated infants and evaluating POCUS efficacy and/or accuracy in detecting ETT position vs. a defined gold-standard method. Three review authors independently assessed the studies' quality and extracted data.

MAIN RESULTS

We identified 14 eligible studies including a total of 602 ETT evaluations in NICU or in the delivery room. In about 80% of cases the gold standard for ETT position verification was CXR. Ultrasound was able to identify the presence of ETT in 96.8% of the evaluations, with a pooled POCUS sensitivity of 93.44% (95% CI: 90.4-95.75%) in detecting an appropriately positioned ETT as assessed by CXR. Bedside ultrasound confirmation was also found to be significantly faster compared to obtaining a CXR.

CONCLUSION

POCUS appears to be a fast and effective technique to identify correct endotracheal intubation in newborns. This review could add value and importance to the use of this promising technique.

'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.

Ultrasound for Endotracheal Tube Tip Position in Term and Preterm Infants

BACKGROUND AND OBJECTIVE

Placing an endotracheal tube (ETT) in neonates is challenging and currently requires timely radiographic confirmation of correct tip placement. The objective was to establish the reliability of ultrasound (US) for assessing ETT position in the neonatal intensive care unit (NICU), time needed to do so, and patients' tolerance.

METHODS

A prospective study on 71 newborns admitted to our NICU whose ETT placement was evaluated with US (ETT-echo) and confirmed on chest X-rays (CXR). Data were collected by 3 operators (2 neonatologists and a resident in pediatrics). The right pulmonary artery (RPA) was used as a landmark for US. The distance between the tip of the ETT and the upper margin of the RPA was measured using US and compared with the distance between the tube's tip and the carina on the CXR.

RESULTS

Seventy-one intubated newborns were included in the study (n = 34 < 1,000 g, n = 18 1,000-2,000 g, n = 19 > 2,000 g). Statistical analysis (Bland-Altman plot and Lin's concordance correlation coefficient) showed an excellent consistency between ETT positions identified on US and chest X-ray. The 2 measures (ETT-echo and CXR) were extremely concordant both in the whole sample and in the subgroups. Minimal changes in patients' vital signs were infrequently observed during US, confirming the tolerability of ETT-echo. The mean time to perform US was 3.2 min (range 1-13).

CONCLUSIONS

ETT-echo seems to be a rapid, tolerable, and highly reliable method worth further investigating for future routine use in neonatology with a view to reducing radiation exposure.