POCUS of the Pediatric Critical Airway, A Prospective Clinical Observational Study

The pediatric airway is markedly different front that of the adult airway, with unique anatomical challenges that can make endotracheal extubation of the pediatric airway more complicated. Pediatric patients are sensitive to small changes in diameter and patients who have been intubated may experience laryngeal edema. This laryngeal edema is multifactorial, but in large part is caused by mechanical pressure or irritation from the endotracheal tube itself. Mucosal ulcerations and laryngeal edema occur in almost all patients intubated for greater than four days. In pediatrics, the laryngeal edema from endotracheal intubation can lead to upper airway obstruction (UOA) with the development of post extubation stridor (PES), and often, respiratory distress. Early identification of patients who are at high risk for PES is critical, as it allows for proper preparation and prevention of complications.

The rates of PES have been estimated between 5% and 54%, widely varied in the literature. Some factors that have been identified as predictive of PES include young age, female gender, previous history of airway difficulties, longer intubation duration, elevated cuff pressure, incorrect endotracheal tube size, airway infection, traumatic intubation, repeated intubation attempts, prolonged intubation, aggressive tracheal aspiration, increased tube mobility, and unintentional extubations.

Recently, ultrasound has been used to help predict those patients who may be at risk for PES. Currently, cuff leak tests have been widely used to predict upper airway patency and are currently standard of care in Pediatric Intensive Care Units across the country, however, the positive predictive value of this test has consistently shown to be low. With ultrasound, a measurement of the laryngeal air column width can be used to predict patients who will develop PES. An observational study done in 2018 at a single, tertiary pediatric hospital showed that laryngeal ultrasound done by experienced ultrasonographers and radiologists prior to extubation could predict patients who would develop PES.

In critical care, there is a significant need to decrease PES rates and POCUS could provide a rapid, reliable, and sensitive assessment of the pediatric patient who is at risk for PES and its complications.

The investigators hypothesize that patients with smaller laryngeal air column width differences on POCUS will have a higher likelihood of developing PES.