Clinical Audit: Optimal Positioning of Endotracheal Tubes in Neonates

Tracheal Length Measurement in Intubated Neonates to Guide the Design and Use of Endotracheal Tube Glottic Depth Markings

Background: Data on neonatal tracheal length are needed to inform the standardization of safety features for endotracheal tubes (ETTs) such as glottic depth markings. Laryngotracheal airway measurements are available from digital imaging in infants and children but not in neonates. We aimed to determine the tracheal length (TL) of intubated preterm and term neonates. Methods: An observational study was performed on 57 neonates of 22–42 weeks’ gestation and <1 week of age. Two clinicians independently reviewed 153 digital chest radiographs to determine the carina position and TL. TL was measured from carina to mid-C4 (cricoid level). We analyzed interrater agreement (within 0.5 vertebral levels) on the position of the carina and TL. TL was plotted as a function of gestational age and weight, using graphical and regression analyses. Results: Carina position ranged from T3 to T5.5, with an interrater agreement of 95%. On image pairs concordant for carina position, TL determinations were virtually identical between readers (mean difference 0.1 mm, 95% CI −0.5–0.6 mm). Average mid-tracheal length overlies the body of T1. In infants aged less than 32 weeks’ gestation, the mid-trachea lies <20 mm from the carina or the larynx. TL linearly correlates with gestational age, but correlation with birthweight best fits a segmented regression with a node at 1 kg. Conclusions: The functional length of the laryngotracheal airway can be reliably measured in sick neonates. It correlates well with gestational age and birthweight, and this information can inform the redesign of ETT markings to promote the safer use of these devices.

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.

Prospective validation of the RAPID clinical risk prediction score in adult patients with pleural infection: the PILOT study

BACKGROUND

Over 30% of adult patients with pleural infection either die and/or require surgery. There is no robust means of predicting at baseline presentation which patients will suffer a poor clinical outcome. A validated risk prediction score would allow early identification of high-risk patients, potentially directing more aggressive treatment thereafter.

OBJECTIVES

To prospectively assess a previously described risk score (the RAPID (Renal (urea), Age, fluid Purulence, Infection source, Dietary (albumin)) score) in adults with pleural infection.

METHODS

Prospective observational cohort study that recruited patients undergoing treatment for pleural infection. RAPID score and risk category were calculated at baseline presentation. The primary outcome was mortality at 3 months; secondary outcomes were mortality at 12 months, length of hospital stay, need for thoracic surgery, failure of medical treatment and lung function at 3 months.

RESULTS

Mortality data were available in 542 out of 546 patients recruited (99.3%). Overall mortality was 10% at 3 months (54 out of 542) and 19% at 12 months (102 out of 542). The RAPID risk category predicted mortality at 3 months. Low-risk mortality (RAPID score 0-2): five out of 222 (2.3%, 95% CI 0.9 to 5.7%); medium-risk mortality (RAPID score 3-4): 21 out of 228 (9.2%, 95% CI 6.0 to 13.7%); and high-risk mortality (RAPID score 5-7): 27 out of 92 (29.3%, 95% CI 21.0 to 39.2%). C-statistics for the scores at 3 months and 12 months were 0.78 (95% CI 0.71-0.83) and 0.77 (95% CI 0.72-0.82), respectively.

CONCLUSIONS

The RAPID score stratifies adults with pleural infection according to increasing risk of mortality and should inform future research directed at improving outcomes in this patient population.

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.

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.

Cost-effectiveness of intrapleural use of tissue plasminogen activator and DNase in pleural infection: evidence from the MIST2 randomised controlled trial

The MIST2 (Second Multicentre Intrapleural Sepsis Trial) trial showed that combined intrapleural use of tissue plasminogen activator (t-PA) and recombinant human DNase was effective when compared with single agents or placebo. However, the treatment costs are significant and overall cost-effectiveness of combined therapy remains unclear.

An economic evaluation of the MIST2 trial was performed to assess the cost-effectiveness of combined therapy. Costs included were those related to study medications, initial hospital stay and subsequent hospitalisations. Outcomes were measured in terms of life-years gained. All costs were reported in euro and in 2016 prices.

Mean annual costs were lowest in the t-PA–DNase group (EUR 10 605 for t-PA, EUR 17 856 for DNase, EUR 13 483 for placebo and EUR 7248 for t-PA–DNase; p=0.209). Mean 1-year life expectancy was 0.988 for t-PA, 0.923 for DNase, and 0.969 for both placebo and t-PA–DNase (p=0.296). Both DNase and placebo were less effective, in terms of life-years gained, and more costly than t-PA. When placebo was compared with t-PA–DNase, the incremental cost per life-year gained of placebo was EUR 1.6 billion, with a probability of 0.85 of t-PA–DNase being cost-effective.

This study demonstrates that combined t-PA–DNase is likely to be highly cost-effective. In light of this evidence, a definitive trial designed to facilitate a thorough economic evaluation is warranted to provide further evidence on the cost-effectiveness of this promising combined intervention.

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.

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.

A randomized, single-blinded, prospective study that compares complications between cuffed and uncuffed nasal endotracheal tubes of different sizes and brands in pediatric patients

STUDY OBJECTIVE

To compare any association between the problematic distal placement of cuffed and uncuffed nasal endotracheal tubes (NETTs) of different sizes and brands in pediatric patients.

DESIGN

Randomized, single-blinded, prospective study.

SETTING

Operating room at The Children's Hospital.

PATIENTS

Pediatric patients (aged 2-18 years) scheduled for dental surgery under general anesthesia whose American Society of Anesthesiologists physical status is not greater than 2.

INTERVENTION

Patients were randomly assigned to preformed cuffed (1) RAE (Ring-Adair-Elwyn) endotracheal tube by Mallinckrodt or (2) nasal AGT NETT by Rüsch.

MEASUREMENTS

The distance between the tube's distal end and the carina was measured using a fiber optic bronchoscope. Problematic placements were defined where the tip of the tubes was within 0.5 cm of carina.

MAIN RESULTS

The odds of a problematic placement was 7 times higher (95% confidence interval of odds ratio, 2.06, 23.4) in patients managed with cuffed tubes than those with uncuffed tubes (P = .002). The distance between the tip of cuffed NETT tubes and carina was significantly less than with uncuffed tubes.

CONCLUSIONS

The chances of possible complications were significantly higher with cuffed NETT. The NETT should be kept at least 0.5 cm above carina to avoid possible complications.

Utilizing nasal-tragus length to estimate optimal endotracheal tube depth for neonates in Taiwan

OBJECTIVE

To assess the application of the nasal-tragus length (NTL) to predict the proper endotracheal tube (ETT) depth; also, as relatively thinner size of Asian than Caucasian, the fitness of using the NTL to estimate the optimal ETT depth for neonates in Taiwan was examined.

METHODS

The newborn infants who do need intubation orally were included. Those with midface dysmorphism, craniofacial anomalies, head trauma and/or facial injury in whom it was unable to measure NTL, were excluded. The data were collected after a satisfactory ETT tip position was confirmed on chest roentgenogram. Equations were established via the polynomial and the linear regression of the NTL and the actual ETT; simplified formulae as NTL+0.5 and NTL+1 were assumed accordingly. Paired t test was used to assess the coefficients.

RESULTS

The 63 neonates, weighing 410 through 4,196 g and with gestation 21 through 41 weeks, were enrolled. No statistical difference was found between the actual ETT depth and the estimated ETT depth via the NTL+1 cm in neonates weighing ≤ 2,500 g (n=41, p=0.06), and also between the actual ETT depth and the estimated ETT depth via the NTL+0.5 cm in group weighing >2,500 g (n=22, p=0.171).

CONCLUSIONS

Using the NTL to predict the optimal ETT depth with the formula, NTL plus 1 cm, was clinically practical for newborn infants in Taiwan weighing ≤ 2,500 g, and a modified formula, NTL plus 0.5 cm, was more suitable for neonates weighing >2,500 g.