Are endotracheal tubes with cuffs suitable for use in children

Endotracheal tubes with cuffs have the wide range of applications. They not only provide stable respiratory support for patients requiring an artificial airway, but also play the vital role in emergency care, ICUs, anesthesiology, and other fields.
but are they suitable for use in children?

Advantages of endotracheal tubes with cuffs
Cuffed endotracheal tubes create a seal between the endotracheal tube and the tracheal wall, ensuring that there is no leakage during controlled positive pressure ventilation and that the inhaled volume is not reduced. Leakage around uncuffed endotracheal tubes is difficult to control, and due to decreased chest wall and lung compliance, effective ventilation is reduced, increasing the risk of aspiration of gastric contents and pharyngeal secretions around the endotracheal tube. Furthermore, leakage of exhaled CO2 can lead to falsely low ETCO2 readings. Other advantages of cuffed endotracheal tubes include more reliable low-flow inhalation anesthesia, a reduced incidence of endotracheal tube reinsertion, and reduced contamination of the operating room with anesthetic gases.

Concerns Regarding the Use of Cuffed Endotracheal Tubes in Children
The debate surrounding the use of cuffed endotracheal tubes in pediatric patients has been ongoing for decades. Many pediatric anesthesiologists recommend against using cuffed endotracheal tubes in children under eight years old. This recommendation is based on the anatomical characteristics of the child's larynx and trachea: infants have a vertically narrow larynx, a short epiglottis, a glottis with an anterior-posterior diameter of approximately 7 mm and a transverse diameter of approximately 4 mm, and the narrowest part of the neonatal airway is approximately 4-5 mm below the glottis, where the submucosal layer of the cricoid cartilage is thicker and contains abundant mucous glands.

From birth to 3 years of age, the larynx grows rapidly in proportion, and the anatomical relationships of the laryngeal structures remain relatively constant. Compared to adults, the reduction in airway cross-sectional area due to tracheal mucosal edema is more significant in infants and young children. In adults, tracheal wall pressure exceeding 30 cmH2O can affect blood flow perfusion pressure, causing tracheal wall ischemia and permanent damage; tracheal perfusion pressure is undoubtedly lower in young children than in adults. The air leak test is commonly used to determine the appropriate tube size. A ​​small air leak at an airway pressure of 25 cmH2O is associated with fewer reports of postoperative respiratory complications, but the air leak test cannot be used to predict post-extubation stridor in children under 7 years of age.

Areas of the airway that are easily damaged in children
The pediatric airway is susceptible to injury at three locations: the glottic opening, the cricoid cartilage (subglottic region), and the mid-trachea. Examination of children after prolonged tracheal intubation often reveals damage at the posterior commissure (where the endotracheal tube is located), the cricoid cartilage, and the area of ​​airway compression (at the cuff of the endotracheal tube). An ideal endotracheal tube should be as narrow as possible at the vocal cords and cricoid cartilage, and yet be able to form an airtight seal in the trachea. A non-cuffed endotracheal tube would be too large at the glottis and cricoid cartilage to achieve an airtight seal.Using a cuffed endotracheal tube may be ideal when the cuff is small enough to fit the child's airway, the volume is just right for sealing the airway or slightly lower, and the pressure exerted on the tracheal wall is low.

Endotracheal tubes with cuffs can be used in children and offer some advantages. However, caution is necessary to ensure that the pressure exerted on the tracheal wall is not excessive. Inflating the cuff arbitrarily is not recommended when the intracuff pressure is unknown. N2O can diffuse into the cuff and significantly increase the intracuff pressure. Future developments in pediatric-specific endotracheal tubes may reduce the incidence of complications.