Cuffed endotracheal tubes (cETT) pose the potential advantage of an infrequent need for reintubation in pediatric patients compared to uncuffed tubes. The aim of this study was to investigate tube exchange rates using second generation Microcuff® pediatric endotracheal tubes (PET) with an adapted sizing recommendation in a large single institution cohort of children and to identify potential variables associated with an elevated risk of tube exchange.

Patient data obtained from the electronic patient data management system of the Department of Anesthesia, University Children's Hospital Zurich, Switzerland, were retrospectively assessed for demographic and anthropometric information, size of the internal tube diameter used for positive pressure ventilation and divergence from the size recommendation chart.

Data from 14,188 children younger than 16 years (median 5.3 years) and weighing at least 3 kg who underwent oral or nasal tracheal intubation using second generation Microcuff® PET between 2009 and 2015 were included. Of 13,219 oral tracheal intubations 12,049 (84.9%) were performed according to the manufacturer's size recommendation and 1170 with divergent endotracheal tubes. The odds ratio (OR) of oral reintubation was 0.13% (95% confidence interval 0.08-0.22%) for cases using the manufacture's size recommendation correctly and 22.74% (95% confidence interval 20.42-25.23%) for patients intubated with a not recommended tube (p < 0.0001).

These findings indicate that the second generation Microcuff® PETs can be reliably used with low tube exchange rates across the entire pediatric age range when the tube size is selected according to the manufacturer's size recommendation chart. Adherence to the manufacturer's tube size recommendation is urgently advised.

Airway injuries are reported among preterm infants with bronchopulmonary dysplasia. We hypothesized that prolonged ventilation in preterm infants is associated with subglottic dilatation that can be reliably evaluated by point of care ultrasonography (POCUS).

All preterm infants (<29-weeks) admitted to the neonatal ICU at the Advent-Health from January-2020 to June-2022 were eligible if they required invasive ventilation for ≤7 days in the first 28 days of life (control) or remained intubated for ≥28 days (prolonged ventilation). Sonography was performed by one technician and all images were reviewed by the pediatric radiologist. The trachea size was measured 3 times by randomly selecting three images. The first 20 scans were also independently reported by a different pediatric radiologist. Intra and inter-observer variability was estimated. Mean trachea size and weight at the time of imaging were compared.

Out of 417 eligible infants; 11 died before 28 days and 163 required ventilation for 8-27 days. Consent missed for 80 infants during COVID-19 pandemic. We enrolled 23 and 28 infants in the control & prolonged ventilation groups, respectively. Inter and intra-observer correlations were 0.83 and 0.97 respectively. Infants in the control group had higher gestation and birth weight. Infants on prolonged ventilation were at higher risk for infections, BPD, longer hospital stay and significant subglottic dilation (4.51 ± 0.04 vs 4.17 ± 0.02 mm, p < 0.01) despite smaller body weight at the time of imaging (884 ± 102 vs 1059 ± 123g, p < 0.01).

Extremely preterm infants on prolonged ventilation are at risk for sub-glottic dilatation that can be reliably measured by POCUS.

In everyday pediatric anesthesia practice, clinicians frequently exchange an already inserted endotracheal tube because of a leak or resistance causing significant morbidity. We investigated the accuracy of two ultrasound measurements; the transverse cricoid diameter and epiphyseal diameter of the distal radius in the prediction of endotracheal tube size that best fits in children compared to age-based formulas.

One hundred children (1-6 years) who underwent elective surgery with endotracheal tube whether cuffed (n = 50) or uncuffed (n = 50) were enrolled. The primary endpoint was the agreement between the reference tube size for which its outer diameter was selected based on transverse cricoid diameter and the final best-fit-ETT. The Correlation and Bland Altman agreement tests were conducted between best-fit-ETT outer diameter and ultrasound-measured outer diameter, and between best-fit-ETT inner diameter and inner diameter calculated by age-based formulas.

The agreement rate between transverse cricoid diameter-based endotracheal tube size and best-fit-ETT size was 88% in cuffed group compared to 90% in uncuffed group. A significant positive correlation was reported between the outer diameter of best-fit-ETT and the outer diameter measured by the two ultrasound methods. A lower degree of positive correlation was reported between the inner diameter of best-fit-ETT, and the inner diameter calculated by age-based formulas. Bland Altman's analysis showed agreement between best-fit-ETT outer diameter and epiphyseal diameter of the distal radius in both groups and with transverse cricoid diameter in the cuffed group, with no agreement with age-based formulas in either group.

Both transverse cricoid diameter and epiphyseal diameter of the distal radius are reliable predictors of the size of best-fit-ETT pediatric endotracheal tube compared to age-based formulas. To save time and effort, we recommend the US measurement of the epiphyseal diameter of distal radius in the preoperative visit and documenting the predicted tube size with the preoperative assessments.

Airway ultrasound allows for precise airway evaluation, particularly for assessing the difficult airway and the potential for front of neck access. Many studies have shown that identification of the cricothyroid membrane by airway ultrasound is more accurate than digital palpation. However, no reports to date have provided clinical evidence that ultrasound identification of the cricothyroid membrane increases the success rate of cricothyroidotomy. This is a narrative review which describes patients with difficult airways for whom airway ultrasound may have been useful for clinical decision making. The role of airway ultrasound for the evaluation of difficult airways is summarized and an approach to the use of ultrasound for airway management is proposed. The goal of this review is to present practical applications of airway ultrasound for patients predicted to have a difficult airway and who undergo cricothyroidotomy.

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.

The rigid cricoid cartilage is functionally the narrowest portion of the larynx. There is some controversy over the shape of the pediatric cricoid cartilage in the transverse plane. It is important to understand the development of the cricoid cartilage so that endo-traceheal tubes can be used more safely.

To determine changes in the internal diameter and shape of the cricoid cartilage during development and explore the implications of those changes for the selection of ETT type and size for children.

The cervical computed tomography scans were reviewed in patients aged 1-20 years. After performing the multiplanar reconstruction and correcting the slant, the transverse and anteroposterior internal diameters of the inlet and outlet of the cricoid cartilage were measured, respectively. The angle between the arch and the lamina of the cricoid cartilage in the middle sagittal plane was measured. The ratios of transverse to anteroposterior diameter for the inlet and outlet of the cricoid cartilage were calculated, respectively.

In females, the internal diameters of the cricoid cartilage increased linearly with age. In males, the internal diameters of the cricoid cartilage exhibited a growth spurt during adolescence. The transverse diameter of the inlet was the smallest diameter of the cricoid cartilage, and the predicting formula of the transverse diameter of the inlet for children aged 1-12 was 0.4 × age (year) + 5.1, R²  = .758. The angle between the arch and lamina of the cricoid cartilage and the ratios of transverse to anteroposterior diameter correlated weakly with age.

The transverse inner diameter of the inlet is the smallest diameter of the cricoid cartilage. The "funnel shape" of the cricoid cartilage remains unchanged during development. The outer diameter should be considered when selecting an endotracheal tube.