Tracheal rapid ultrasound exam (T.R.U.E.) for confirming endotracheal tube placement during emergency intubation

doi:10.1016/j.resuscitation.2011.05.016

Resuscitation

Volume 82, Issue 10, October 2011, Pages 1279-1284

https://doi.org/10.1016/j.resuscitation.2011.05.016 Get rights and content

Abstract

Objectives

This study aimed to assess the diagnostic accuracy and timeliness of using tracheal ultrasound to examine endotracheal tube placement during emergency intubation.

Methods

This was a prospective, observational study, conducted at the emergency department of a national university teaching hospital. Patients received emergency intubation because of impending respiratory failure, cardiac arrest, or severe trauma. The tracheal rapid ultrasound exam (T.R.U.E.) was performed during emergency intubation with the transducer placed transversely at the trachea over the suprasternal notch. Quantitative waveform capnography was used as the criterion standard for confirmation of tracheal intubation. The main outcome was the concordance between the T.R.U.E. and the capnography.

Results

A total of 112 patients were included in the analysis, and 17 (15.2%) had esophageal intubations. The overall accuracy of the T.R.U.E. was 98.2% (95% confidence interval [CI]: 93.7–99.5%). The kappa (κ) value was 0.93 (95% CI: 0.84–1.00), indicating a high degree of agreement between the T.R.U.E. and capnography. The sensitivity, specificity, positive predictive value, and negative predictive value of the T.R.U.E. were 98.9% (95% CI: 94.3–99.8%), 94.1% (95% CI: 73.0–99.0%), 98.9% (95% CI: 94.3–99.8%) and 94.1% (95% CI: 73.0–99.0%). The median operating time of the T.R.U.E. was 9.0 s (interquartile range [IQR]: 6.0, 14.0).

Conclusions

The application of the T.R.U.E. to examine endotracheal tube placement during emergency intubation is feasible, and can be rapidly performed.

Introduction

Establishing a secure airway in critically ill patients is a primary step during resuscitation. According to the 2010 Advanced Cardiac Life Support (ACLS) guidelines, adequate support of ventilation during resuscitation is essential.¹ Proper endotracheal tube intubation provides definitive airway control. Nevertheless, unrecognized endotracheal tube misplacement can lead to significant mortality and morbidity, and is more likely to occur during emergent situations. The reported incidence of esophageal intubation was about 6–16% during emergency intubation.2, 3 Thus, early detection of accidental esophageal intubation is a primary focus during resuscitation.

Many traditional methods can be employed to confirm endotracheal tube placement, including direct visualization of the vocal cords, observation of chest movement, and chest and gastric auscultation. Each of these methods has limitations, and is not entirely reliable in the emergency setting.4, 5 Studies found that quantitative capnography is the most sensitive tool for confirming tracheal intubation.4, 5, 6 According to the 2010 ACLS guidelines, quantitative waveform capnography is recommended as the most reliable method for confirming endotracheal tube placement.¹ However, capnography is still not widely available in some emergency departments (EDs) and intensive care units (ICUs).⁷ A confirmation technique that is widely available and accurate would be desirable when waveform capnography is not available.

Ultrasound is a common examination tool in many EDs and ICUs. To assist with airway management in critically ill patients, ultrasound is very useful due to its low-cost and portable capability.⁸ Several studies have provided promising results of the use of ultrasound for the confirmation of endotracheal tube placement in cadaveric models and in patients in well-controlled environments.9, 10, 11, 12, 13, 14, 15, 16 Two recent studies showed up to 100% of sensitivity and specificity of tracheal ultrasound for endotracheal tube placement confirmation in live humans under a well-controlled operating room setting.14, 15 To date, few studies have been conducted in emergency settings, so that validation of this potentially useful technique in emergent situations is urgently needed.

We proposed a tracheal rapid ultrasound examination (T.R.U.E.) method for rapid and accurate confirmation of the endotracheal tube position during emergency intubation. This study aimed to assess the diagnostic accuracy and timeliness of the T.R.U.E. in confirming endotracheal tube position during emergency intubation.

Section snippets

Study design and setting

This was a prospective, single-center, observational study, conducted between March 2010 and December 2010. The study protocol was approved by the Institutional Review Board of the National Taiwan University Hospital with a waiver of informed consents. All subjects were recruited from the ED of National Taiwan University Hospital, which is a 2000-bed, tertiary teaching hospital. The emergency department cares for more than 100,000 patients each year.

Selection of participants

Patients were prospectively enrolled during

Results

Of the 173 eligible patients, a total of 112 (64.7%) patients, with ages of 24–94 years old, were included in the final analyses, between March 2010 and December 2010 (Fig. 2). Their demographics and clinical characteristics are listed in Table 1. The mean age was 67.4 ± 17.6 years. The mean BMI was 23.1 ± 4.8 kg/m². Among 112 patients, 18 out-of-hospital and 11 in-hospital cardiac arrest patients were intubated. The remaining 83 patients were intubated for other medical emergencies. The mean

Discussion

This prospective study aimed to assess accuracy and timeliness of tracheal ultrasound for determining endotracheal tube placement during emergency intubation. In this study, tracheal ultrasound achieved high sensitivity and specificity for confirming endotracheal tube placement. Therefore, ultrasound can serve as a good diagnostic tool for confirming tracheal intubation during resuscitation.

According to the 2010 ACLS guidelines, endotracheal tube position should be verified by both clinical

Conclusions

This prospective study indicated that the application of the T.R.U.E. to examine endotracheal tube placement during emergency intubation is feasible, and can be rapidly performed. Thus, tracheal ultrasound can be considered as the secondary confirmation method for endotracheal tube placement during resuscitation.

Conflicts of interest statement

None.

Acknowledgement

We would like to thank Fu-Chang Hu, MS, ScD, for suggestions for statistical analysis and assistance with statistical computing.

References (28)

T. Takeda et al.
The assessment of three methods to verify tracheal tube placement in the emergency setting
Resuscitation
(2003)
G. Ma et al.
The sensitivity and specificity of transcricothyroid ultrasonography to confirm endotracheal tube placement in a cadaver model
J Emerg Med
(2007)
T.J. Milling et al.
Transtracheal 2-d ultrasound for identification of esophageal intubation
J Emerg Med
(2007)
S.L. Werner et al.
Pilot study to evaluate the accuracy of ultrasonography in confirming endotracheal tube placement
Ann Emerg Med
(2007)
T. Byrt et al.
Bias, prevalence and kappa
J Clin Epidemiol
(1993)
C. Hernandez et al.
C.A.U.S.E.: Cardiac arrest ultra-sound exam—a better approach to managing patients in primary non-arrhythmogenic cardiac arrest
Resuscitation
(2008)
ECC Committee, Subcommittees and Task Forces of the American Heart Association
2010 American Heart Association Guidelines for cardiopulmonary resuscitation and emergency cardiovascular care. Part 8.1: Adjuncts for airway control and ventilation
Circulation
(2010)
D.E. Schwartz et al.
Death and other complications of emergency airway management in critically ill adults. A prospective investigation of 297 tracheal intubations
Anesthesiology
(1995)
T.C. Mort
Unplanned tracheal extubation outside the operating room: a quality improvement audit of hemodynamic and tracheal airway complications associated with emergency tracheal reintubation
Anesth Analg
(1998)
S. Grmec
Comparison of three different methods to confirm tracheal tube placement in emergency intubation
Intensive Care Med
(2002)

S. Knapp et al.

The assessment of four different methods to verify tracheal tube placement in the critical care setting

Anesth Analg

(1999)

N.M. Deiorio

Continuous end-tidal carbon dioxide monitoring for confirmation of endotracheal tube placement is neither widely available nor consistently applied by emergency physicians

Emerg Med J

(2005)

A. Sustić

Role of ultrasound in the airway management of critically ill patients

Crit Care Med

(2007)

D.T. Raphael et al.

Ultrasound confirmation of endotracheal tube placement

J Clin Ultrasound

(1987)

Cited by (151)

Confirmatory methods for endotracheal tube placement in out-of-hospital settings: A systematic review of the literature
2024, Heliyon
Confirming proper placement of an endotracheal tube (ETT) is important, as accidental misplacements may occur and lead to critical injuries, potentially leading to adverse outcomes. Multiple methods are available for determining the correct ETT placement in prehospital care.
To assess the accuracy and reliability of the different methods used to confirm endotracheal intubation in prehospital settings.
A comprehensive literature search was performed in the MEDLINE, EMBASE, Scopus, and Web of Science databases for studies that were published between 1-June-1992 and 12-June-2022 using a combination of predetermined search terms. Studies that met the inclusion criteria were included and assessed for risk of bias using “Risk of Bias in Non-randomized Studies of Intervention” tool.
Of the 1016 identified studies, nine met the inclusion criteria. Capnography and point-of-care ultrasound showed high sensitivity and specificity rates when applied to confirm ETT placement in prehospital care. Other methods including capnometry, colorimetric detectors, ODDs, and auscultation showed varied sensitivity and specificity. Patient comorbidities and device failure contributed to decreased accuracy rates in prehospital care. Capnography was less reliable in distinguishing between endotracheal intubation and right main stem intubation, which is known as a complication in out-of-hospital endotracheal intubation. Point-of-care ultrasound was more accurate and reliable in detecting oesophageal and endobronchial misplacements. ETCO₂ monitors, i.e., capnometry and colorimetric detectors, were less reliable in patients with low perfusion states.
This systematic review showed that there is no single method with 100% accuracy in confirming the correct ETT placement and detecting the occurrence of accidental oesophageal or endobronchial misplacements in prehospital care. Further studies with a larger sample size are needed to assess the accuracy of multiple confirmatory methods in prehospital settings.
The Evolving Role of Ultrasound in Prehospital and Emergency Medicine
2023, Physician Assistant Clinics
Ultrasound for Assessment and Follow-up of Airway Stenosis
2022, Annals of Thoracic Surgery
Ultrasound is a reliable tool for airway assessment and management. We evaluated the accuracy of ultrasound in the preprocedure planning and follow-up evaluation of patients undergoing airway stenting for benign upper airway stenosis.
This was a retrospective single center study on patients with benign upper airway stenosis treated with airway stenting. Ultrasound evaluated the characteristics of the stenosis (distance from vocal folds, diameter, and length) before treatment and any complications after treatment; these results were then statistically compared with those obtained by computed tomography, taking the endoscopy as the reference method.
Twenty-seven patients were evaluated. Ultrasound was significantly correlated with endoscopy and computed tomography scan measurements as distance of stenosis from vocal folds (r = 0.88; P < .001 and r = 0.87; P < .001, respectively), diameter of the stenosis (r = 0.97; P < .001 and r = 0.97; P < .001, respectively), and length of the stenosis (r = 0.97; P < .001 and r = 0.97; P < .001, respectively). Four out of 27 (15%) patients presented complications after treatment as stent migration (n = 2; 7%); stent obstruction (n = 1; 4%), and granulation of vocal fold (n = 1; 4%). All complications but granulation of vocal fold were correctly depicted by ultrasound and computed tomography without significant difference in comparison to endoscopy (P = .87)
Ultrasound is a promising tool in assessment of airway stenosis and follow-up of patients after stenting; it may be routinely used in adjunction to computed tomography and/or endoscopy in this setting, if our results are corroborated by a future larger study.
Point-of-Care Ultrasound Curriculum for Endotracheal Tube Confirmation for Pediatric Critical Care Transport Team Through Remote Learning and Teleguidance
2022, Air Medical Journal
Point-of-care ultrasound (POCUS) is used to manage patients in real time. This study aimed to teach pediatric critical care team members to use POCUS for endotracheal tube (ETT) placement confirmation. A secondary aim was to assess the feasibility of a remote curriculum for this purpose.
The Kern 6-step approach was used. The curriculum involved virtual didactics, asynchronous learning modules, and remote hands-on sessions using teleguidance with the Butterfly IQ+ probe, Butterfly Network, Inc, Guilford, CT. Participants learned direct and indirect methods of ETT placement confirmation and were directed to practice independently. Outcomes included attitudes and satisfaction, knowledge and skills acquisition and retention, and the use of POCUS on shift.
Ten participants completed the curriculum. The average knobology and quiz scores improved by 29.3% and 20.8%, respectively. Improvement was sustained at re-evaluation. Seven of 10 participants performed independent scans. At the 3-month reassessment, most demonstrated mastery of thoracic scans. All required prompting for satisfactory tracheal scans. All felt positively toward POCUS and the remote curriculum.
Pediatric critical care team members acquired and retained knowledge and skills for POCUS basics and ETT placement confirmation through a remote curriculum. Participants were satisfied with the course. Further studies are needed to reassess longer-term knowledge and skill retention and the effects on patient outcomes.
Perioperative Point-of-Care Ultrasound
2021, Advances in Anesthesia
Measurement of the subglottic diameter of the trachea and its distance from the skin by ultrasonography in children
2021, International Journal of Pediatric Otorhinolaryngology
To investigate the relationship between age, sex, height, weight and body mass index (BMI) by measuring the subglottic diameter of the trachea (SDT) and its distance to the skin by ultrasonography (US) in children.
This prospective study included a total of 234 children, 104 girls and 134 boys, with ages ranging from 3 to 17 years. Demographic data including sex, age, height, weight and BMI were recorded. The SDT and its distance to the skin was measured with a 14L5 high-frequency surface transducer. The correlation of SDT and its distance to the skin with basic descriptive data was investigated. Statistical analyses used were Mann–Whitney U, Kruskal–Wallis and Spearman correlation tests.
No significant difference was found among the median SDT and distance of the trachea from the skin values for boys (10.85 mm) and girls (11.15 mm) (p = 0.58). The distance of the trachea from the skin was greater in girls (5.5 mm) than in boys (4.75 mm) (p = 0.009). Median SDT values were 9.4 mm, 11.2 mm, and 13.35 mm in age groups 1, 2, and 3, respectively. There were highly significant strong positive correlations between SDT with age (p = 0.001, r = 0.78), height (p = 0.001, r = 0.76), and weight (p = 0.001, r = 0.70), and a highly significant moderate positive correlation between SDT with BMI (p = 0.001, r = 0.43). Median distance values of the trachea from the skin were 4.6 mm, 5.2 mm, and 6.2 mm in age groups 1, 2, and 3, respectively. There were moderate positive correlations between distance of the trachea from the skin with age (p = 0.001, r = 0.41), height (p = 0.001, r = 0.42), weight (p = 0.001, r = 0.53), and BMI (p = 0.001, r = 0.54).
US is an accurate, safe, inexpensive, non-invasive and accessible method for objective evaluation of SDT and its distance to the skin. There is a positive correlation between age, height, weight, and BMI with SDT and its distance to the skin in healthy children.

View all citing articles on Scopus

^☆: Trial Registration: ClinicalTrials.gov number: NCT01148732.

^☆☆: A Spanish translated version of the abstract of this article appears as Appendix in the final online version at doi:10.1016/j.resuscitation.2011.05.016.

View full text

Clinical paperTracheal rapid ultrasound exam (T.R.U.E.) for confirming endotracheal tube placement during emergency intubation☆,☆☆

Abstract

Objectives

Methods

Results

Conclusions

Introduction

Section snippets

Study design and setting

Selection of participants

Results

Discussion

Conclusions

Conflicts of interest statement

Acknowledgement

Resuscitation

J Emerg Med

J Emerg Med

Ann Emerg Med

J Clin Epidemiol

Resuscitation

2010 American Heart Association Guidelines for cardiopulmonary resuscitation and emergency cardiovascular care. Part 8.1: Adjuncts for airway control and ventilation

Circulation

Death and other complications of emergency airway management in critically ill adults. A prospective investigation of 297 tracheal intubations

Anesthesiology

Unplanned tracheal extubation outside the operating room: a quality improvement audit of hemodynamic and tracheal airway complications associated with emergency tracheal reintubation

Anesth Analg

Comparison of three different methods to confirm tracheal tube placement in emergency intubation

Intensive Care Med

The assessment of four different methods to verify tracheal tube placement in the critical care setting

Anesth Analg

Continuous end-tidal carbon dioxide monitoring for confirmation of endotracheal tube placement is neither widely available nor consistently applied by emergency physicians

Emerg Med J

Role of ultrasound in the airway management of critically ill patients

Crit Care Med

Ultrasound confirmation of endotracheal tube placement

J Clin Ultrasound

Clinical paper
Tracheal rapid ultrasound exam (T.R.U.E.) for confirming endotracheal tube placement during emergency intubation☆,☆☆