From the Guidelines
The pediatric airway is narrowest at the subglottis, specifically at the cricoid cartilage level. This is based on the most recent and highest quality evidence from the field of pediatrics, which highlights the significance of the subglottic region as the narrowest part of the pediatric airway 1. The subglottis is the area below the vocal cords and above the trachea, and its narrowness is due to the complete ring formed by the cricoid cartilage. This anatomical feature is crucial in understanding the management of pediatric airways, especially in conditions such as infantile hemangioma, where airway obstruction can occur 1.
Key points to consider:
- The subglottic region is the narrowest part of the pediatric airway, making it prone to obstruction during respiratory illnesses or intubation.
- The cricoid cartilage forms a complete ring, which cannot expand when swollen, increasing the risk of airway compromise in children.
- Understanding the anatomy of the pediatric airway is essential for healthcare providers to manage pediatric airways effectively, select appropriate endotracheal tube sizes, and anticipate potential complications during respiratory emergencies in children.
In clinical practice, recognizing the subglottis as the narrowest part of the pediatric airway is vital for preventing and managing airway obstruction, which can significantly impact morbidity, mortality, and quality of life in pediatric patients 1.
From the Research
Location of the Narrowest Portion of the Pediatric Airway
The location of the narrowest portion of the pediatric airway is a topic of ongoing research and debate.
- Studies have investigated the dimensions of the pediatric larynx, including the glottis, cricoid, and subcricoid regions, to determine the narrowest portion 2, 3, 4, 5, 6.
- According to a study published in 2018, the narrowest portion of the pediatric larynx is located in the subcricoid region, with the mean anterior-posterior diameter being the shortest at this level 2.
- However, another study published in 2009 found that the glottis, rather than the cricoid, was the narrowest portion of the pediatric airway 3.
- A study published in 2017 found that the cricoid ring is generally round in children older than 1 year, but elliptical in infants, with the anterior-posterior dimension being larger than the transverse dimension 4.
- A review article published in 2015 discussed the implications of recent studies on pediatric airway anatomy, suggesting that the narrowest segment may be at or just below the glottic opening, and that the airway is elliptical in shape rather than circular 5.
- A study published in 2019 found that the narrowest part of the pediatric trachea is the transverse diameter at the infraglottic level, and that the traditional age-based formula for predicting endotracheal tube size may not be accurate 6.
Comparison of Locations
- The cricoid region is often considered the narrowest portion of the pediatric airway, but studies have shown that this may not always be the case 2, 3, 4, 5, 6.
- The glottis and subcricoid regions have also been identified as potential narrowest portions of the pediatric airway 2, 3.
- The infraglottic level has been found to be the narrowest part of the pediatric trachea, with the transverse diameter being the smallest 6.
Key Findings
- The pediatric airway is a complex and dynamic structure, and its anatomy can vary depending on age and development 2, 3, 4, 5, 6.
- Recent studies have challenged traditional assumptions about the pediatric airway, and further research is needed to fully understand its anatomy and implications for clinical practice 2, 3, 4, 5, 6.