Anesthesia

Introduction: This case report describes the successful use of combined ultrasound scan (USS) and fiberoptic bronchoscopy in two cases for insertion of a percutaneous dilatational tracheostomy (PDT).

Case Description: Two patients were scheduled for percutaneous dilatational tracheostomy. The first patient was a 56 year old female and the second patient was 63 year old male.

Methods: The patient’s neck was exposed and scanned in the neutral position to determine the need for an extended or regular tracheostomy tube. The neck was then extended, sterilized and draped. Higher frequency linear probe (7.5 MHZ) in a sterile sheath and fiberoptic bronchoscopy were used with two intensivists and a nurse in attendance. The midline structures and cricoid cartilage were identified in out of plane position. The probe was then rotated 90 degrees to obtain a longitudinal view of the cricothyroid cartilage, cricoid cartilage and tracheal rings. The needle was inserted between the 2^nd and 3^rd tracheal rings using in plane mode, with the goal of placing the puncture site between 11 and 1 o’clock on the bronchoscopy view as close as possible to the midline. The bronchoscope was used to visualize the needle insertion point and to avoid injury to the posterior wall of the trachea.

Discussion: USS of the upper airway can provide important anatomical information that would not be evident upon clinical examination alone. This includes information about the anatomy of the pre- and paratracheal regions and identification of vulnerable structures, such as blood vessels and the thyroid gland, thereby avoiding immediate vascular complications. It also enables the clear visualization of the tracheal rings, thereby facilitating positioning of the tracheal puncture and correct midline placement. Real-time US guidance makes it possible to follow the needle path during tracheal puncture and to determine the final position of the tracheostomy tube. However, intraluminal air prevents the visualization of structures such as the posterior pharynx and the posterior wall of the trachea with USS. Therefore, injury to the posterior wall of the trachea cannot be completely avoided. However, we believe that the combined use of fiberoptic bronchoscopy makes it safer by minimizing injury to the posterior tracheal wall, avoiding false passages and tracheal cartilage rupture.