Radiologic and surgical evidence of pre-tracheal anatomies for safe procedures in older adult oncologic patients: educational implications for elective or emergent tracheotomies among novice practitioners.

Background: Most of the current tracheotomy-related recommendations centers on indications, evaluations and post-treatment care, while on an educational standpoint, little knowledge of the pre-tracheal anatomies/variations can be found, which may play an important role in avoiding tracheotomy-related complications. This study aims to assess the anatomical relationship and age-related variability of the anatomies in the pre-tracheal space in older adult patients with head and neck cancers and to guide tracheotomy with clinical evidence for either planned or improvised procedures. Methods: From January 2019 to February 2022, hospitalized head and neck cancer patients aged over 65 years (127 cases) and under 65 years (74 cases) were enrolled in this study as the observation and the control groups, respectively. All these patients received contrast-enhanced computed tomography (CECT) scans, ablative operations and tracheotomies for primary head and neck cancers. The radiographic reconstructions of vascular morphologies were compared, focusing on three target vessels: anterior jugular veins (AJVs), innominate arteries (IAs) and inferior thyroid vascular plexus (ITVPs). The upper locations of the isthmus, and the largest diameters of thyroid glands were compared as well. In addition, surgical exposure of those vessels was recorded during tracheostomies to verify these radiologic findings. The tracheotomy procedure-related complications were also compared. Results: A total number of 201 patients (115 males and 86 females) were identified in this study. The mean age of the older adult group reached 72.0 years (range, 65-87 years), most (86/127, 67.7%) were with oral cancer. The ratio of single-branch type AJVs in the older-adult group (15/126, 11.9%) was higher than that in the non-older adult counterpart (6/73, 8.2%), though no statistical difference was found (P=0.701). Radiologically speaking, the IAs were mainly categorized as the low-bifurcation (104/201, 51.7%), high-bifurcation (37/201, 18.4%), high-platform (27/201, 13.4%), low-platform (30/201, 14.9%), and variant types (3/201, 1.5%). Age-related changes of IA types were found between the older and the non-older adult groups (P<0.01), especially for the platform IAs types, which might interfere with intraoperative tracheal exposure. This phenomenon was also closely related to our intraoperative tracheotomy findings (r Conclusions: Considering the age-related changes, the evaluation of the pre-tracheal anatomies based on radiographic evidence can facilitate safer tracheotomies in older adult patients. Besides, educational implications for impromptu tracheotomies may also be drawn with knowledge of these variable anatomies.