Adherence to Endotracheal Tube Depth Guidelines and Incidence of Malposition in Infants and Children

Predicting optimal endotracheal tube size and depth in pediatric patients using demographic data and machine learning techniques

BACKGROUND

Use of endotracheal tubes (ETTs) with appropriate size and depth can help minimize intubation-related complications in pediatric patients. Existing age-based formulae for selecting the optimal ETT size present several inaccuracies. We developed a machine learning model that predicts the optimal size and depth of ETTs in pediatric patients using demographic data, enabling clinical applications.

METHODS

Data from 37,057 patients younger than 12 years who underwent general anesthesia with endotracheal intubation were retrospectively analyzed. Gradient boosted regression tree (GBRT) model was developed and compared with traditional age-based formulae.

RESULTS

The GBRT model demonstrated the highest macro-averaged F1 scores of 0.502 (95% CI 0.486, 0.568) and 0.669 (95% CI 0.640, 0.694) for predicting the uncuffed and cuffed ETT size (internal diameter [ID]), outperforming the age-based formulae that yielded 0.163 (95% CI 0.140, 0.196, P < 0.001) and 0.392 (95% CI 0.378, 0.406, P < 0.001), respectively. In predicting the ETT depth (distance from tip to lip corner), the GBRT model showed the lowest mean absolute error (MAE) of 0.71 cm (95% CI 0.69, 0.72) and 0.72 cm (95% CI 0.70, 0.74) compared to the age-based formulae that showed an error of 1.18 cm (95% CI 1.16, 1.20, P < 0.001) and 1.34 cm (95% CI 1.31, 1.38, P < 0.001) for uncuffed and cuffed ETT, respectively.

CONCLUSIONS

The GBRT model using only demographic data accurately predicted the ETT size and depth. If these results are validated, the model may be practical for predicting optimal ETT size and depth for pediatric patients.

A new formula based on height for determining endotracheal intubation depth in pediatrics: A prospective study

STUDY OBJECTIVE

The main objective was to devise an endotracheal intubation formula based on pediatric patients' strongly correlated growth parameters. The secondary objective was to compare the accuracy of the new formula to the age-based formula from Advanced Pediatric Life Support Course (APLS formula) and the middle finger length-based formula (MFL-based formula).

DESIGN

A prospective, observational study.

SETTING

Operation.

PATIENTS

111 subjects age 4-12 years old undergoing elective surgeries with general orotracheal anesthesia.

INTERVENTIONS AND MEASUREMENTS

Growth parameters, including age, gender, height, weight, BMI, middle finger length, nasal-tragus length, and sternum length, were measured before surgeries. Tracheal length and the optimal endotracheal intubation depth (D) were measured and calculated by Disposcope. Regression analysis were used to establish a new formula for predicting the intubation depth. A self-controlled paired design was used to compare the accuracy of the intubation depth between the new formula, APLS formula, and MFL-based formula.

MAIN RESULTS

Height (R = 0.897, P < 0.001) was strongly correlated to tracheal length and the endotracheal intubation depth in pediatric patients. New formulae basing on height were established, including new formula 1: D (cm) = 4 + 0.1 × Height (cm) and new formula 2: D (cm) = 3 + 0.1 × Height (cm). Via Bland-Altman analysis, the mean differences for new formula 1, new formula 2, APLS formula and MFL-based formula were - 0.354 cm (95% LOA, -1.289 to 1.998 cm), 1.354 cm (95% LOA, -0.289 to 2.998 cm), 1.154 cm (95% LOA, -1.002 to 3.311 cm), -0.619 cm (95% LOA, -2.960 to 1.723 cm), respectively. The rate of optimal intubation for new formula 1 (84.69%) was higher than for new formula 2 (55.86%), APLS formula (61.26%), and MFL-based formula. (69.37%).

CONCLUSIONS

The prediction accuracy for intubation depth of the new formula 1 was higher than the other formulae. The new formula based on height: D (cm) = 4 + 0.1 × Height (cm) was preferable to APLS formula and MFL-based formula with a high incidence of appropriate endotracheal tube position.

Applications of Airway Ultrasound for Endotracheal Intubation in Pediatric Patients: A Systematic Review

Endotracheal intubation is a challenging procedure for pediatric patients. Airway ultrasound as a new technology is suitable for aiding this process, but its diagnostic value remains unclear. We searched MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, and the Chinese biomedical literature database to summarize specific applications of airway ultrasound in each step of endotracheal intubation in pediatric patients. Diagnostic accuracy and 95% confidence interval were used as outcomes. In total, 33 studies (6 randomized controlled trials and 27 diagnostic studies) with 1934 airway ultrasound examinations were included. Population included neonates, infants, and older children. Airway ultrasound could be used to determine the endotracheal tube size and confirm endotracheal intubation and intubation depth; the diagnostic accuracy for all these factors was 23.3-100%, 90.6-100%, and 66.7-100%, respectively. Furthermore, the accuracy of airway ultrasound in predicting endotracheal tube size was consistently higher than traditional methods, such as height formula, age formula, and the width of the little finger. In conclusion, airway ultrasound has unique advantages for confirming successful endotracheal intubation in pediatric patients, and it may become an effective auxiliary tool in this field. There is a need to develop a unified airway ultrasound protocol to conduct clinical trials and practice in the future.

Tracheal Tube Misplacement after Emergency Intubation in Pediatric Trauma Patients: A Retrospective, Exploratory Study

Inadvertent tracheal tube misplacement and particularly endobronchial intubation are well-known complications of emergency endotracheal intubation (ETI) in pediatric trauma patients, which require repositioning of the tube to avoid impairment of gas exchange. The main aim of study was to identify the frequency of tube misplacement and associated factors of pediatric trauma patients who received ETI either by prehospital physician-staffed emergency medical service (EMS), or at emergency department (ED) admission to a single level-1 trauma center. Sixty-five patients (median age 14 years and median injury severity score 29) were included. Of these, 30 underwent helicopter EMS ETI, 29 ground EMS ETI, and 6 ED ETI. Seventeen cases (26%) of tracheal tube misplacement were recognized. After multivariable analysis, tracheal tube misplacement was independently negatively associated with body weight (OR 0.86; 95% CI, 0.76–0.99; p = 0.032) and helicopter EMS ETI (OR 0.20; 95% CI, 0.04–0.97; p = 0.036). Two of nineteen patients received tube thoracostomy due to endobronchial intubation. Mortality and length of stay were comparable in patients with misplaced tubes and correctly placed tubes. The results suggest that particularly small children require attention to avoid tracheal tube misplacement, which emphasizes the need for special training. Helicopter EMS physicians’ expertise might be beneficial in prehospital pediatric trauma patients requiring advanced airway management.

Diagnostic value of pleural ultrasound to refine endotracheal tube placement in pediatric intensive care unit

AIM

To assess the diagnostic performance of a simplified lung point-of-care ultrasound (POCUS) to confirm the correct positioning of an endotracheal tube (ETT) in a pediatric intensive care unit (PICU) used to chest radiography (CXR), and to compare the time to obtain the ETT position between POCUS and CXR.

METHODS

We conducted a single-center prospective study in critically ill children requiring urgent endotracheal intubation. Esophageal tube malposition was first avoided using auscultation and end-tidal CO2. The ETT position was assessed with CXR and lung POCUS using the lung sliding sign on a pleural window. All of the investigators had to read guidelines and received 1-h training on the technical aspects of lung sliding. The primary objective was the accuracy of POCUS in confirming correct nonselective endotracheal intubation as compared with CXR.

RESULTS

A total of 71 patients were included from December 2016 to November 2018. CXR identified proper nonselective ETT placement in 43 of 71 (61%) patients, while the rate for selective intubation was 39%. The sensitivity and specificity of POCUS as compared with CXR were 77% and 68%, respectively. Median time to POCUS was significantly shorter than CXR (2 min to perform POCUS, 10 min to obtain radiographs, p<10-4).

CONCLUSION

Pleural ultrasound, although faster than CXR, appears to be inadequate for identifying selective ETT after urgent intubation in a PICU less accustomed to this kind of ultrasound. In this heterogeneous and fragile population, timely POCUS may remain useful at the bedside as compared with auscultation, aiming at guiding optimal ETT placement and reducing respiratory complications, provided by trained physicians.

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.

Point-of-Care Ultrasound in Sternal Notch Confirms Depth of Endotracheal Tube in Children

OBJECTIVES

To determine if a saline-filled cuff seen at the suprasternal notch on ultrasound corresponds to correct endotracheal tube depth on a chest radiograph (tip at/below clavicle AND ≥ 1 cm above carina).

DESIGN

Prospective observational study.

SETTING

Tertiary Care Pediatric hospital.

PATIENTS

Patients between the ages of 0-18 years requiring nonemergent cardiac catheterizations and endotracheal intubation with a cuffed endotracheal tube were included in the study. Children with anticipated or known difficult airways were excluded.

INTERVENTIONS

Ultrasound evaluation of the neck following saline inflation of the endotracheal tube cuff.

MEASUREMENTS AND MAIN RESULTS

Ultrasonography of the patient's neck was performed following intubation by a pediatric anesthesiologist. A linear probe was used in transverse axis to identify the saline-filled cuff starting at the suprasternal notch and moving cephalad. A cine-fluoroscopic image, similar to a chest radiograph, was obtained to ascertain the endotracheal tube depth after the cuff was identified sonographically. Endotracheal tube cuffs seen on ultrasound at the suprasternal notch were compared with the endotracheal tube depth on the cine-fluoroscopic image. A total of 75 children were enrolled in the study. The endotracheal tube was seen sonographically at the suprasternal notch in 70 patients of which 60 had complete data (an adequate chest radiograph available for review). Patient ages ranged from 2 months to 18 years with a median age of 4 years. The median endotracheal tube tip to carina distance was 2.4 cm (interquartile range, 1.75-3.3 cm.) The endotracheal tube tip to carina distance was greater than or equal to 1 cm in 57 out of the 60 patients. Endotracheal tube cuff at the suprasternal notch on ultrasound corresponded with correct endotracheal tube depth on chest radiograph with an accuracy of 95% (CI, 86-98%).

CONCLUSIONS

Visualization of the cuff at the suprasternal notch by ultrasound demonstrates potential as a means of confirming correct depth of the endotracheal tube following endotracheal intubation.

Impact of changes in head position during head and neck surgery on the depth of tracheal tube intubation in anesthetized children

Background

The classic formula has been used to estimate the depth of tracheal tube intubation in children for decades. However, it is unclear whether this formula is applicable when the head and neck position changes intraoperatively.

Methods

We prospectively reviewed the data of 172 well-developed children aged 2–12 years (64.0% boys) who underwent head and neck surgery under general anesthesia. The distances from the tracheal carina to the endotracheal tube tip (CT), from the superior margin of the endotracheal tube tip to the vocal cord posterior commissure (CV), and from the tracheal carina to the posterior vocal commissure (TV) were measured in the sniffing position (maximum), neutral head, and maximal head flexion positions.

Results

Average CT and CV in the neutral head position were 4.33 cm and 10.4 cm, respectively. They increased to 5.43 cm and 11.3 cm, respectively, in the sniffing position, and to 3.39 cm and 9.59 cm, respectively, in the maximal flexion position (all P-values < 0.001). TV remained unchanged and was only dependent on age. After stratifying patients by age, similar results were observed with other distances. CT and CV increased by 1.099 cm and 0.909 cm, respectively, when head position changed from neutral head to sniffing position, and decreased by 0.947 cm and 0.838 cm, respectively, when head position changed from neutral head to maximal flexion.

Conclusion

Change in head position can influence the depth of tracheal tube intubation. Therefore, the estimated depth should be corrected according to the surgical head position.