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.