To evaluate the clinical relevance of thyroid isthmus penetration during percutaneous dilatational tracheostomy (PDTS) and to explore the role of ultrasound (US) in procedural guidance and patient selection.

Single-center, prospective interventional study.

Intensive care unit of a tertiary academic hospital.

Adult patients requiring tracheostomy due to prolonged mechanical ventilation or neurological impairment.

Following pre-procedural ultrasound assessment, patients deemed suitable for PDTS were allocated to either a landmark-based technique (Group A) or ultrasound-guided technique (Group B). Ultrasound was also used for post-puncture documentation of guidewire position. Bronchoscopic verification was performed in all cases.

Measurements and Main Results: Among 180 tracheostomies performed, 100 PDTS procedures were analyzed (51 Group A, 49 Group B). In 68% of cases, the tracheostomy trajectory traversed the thyroid isthmus. Early complication rates were similar between trans-isthmic and non-trans-isthmic procedures (4.4% vs . 3.1%; p  = 1.00) and between Group A and Group B (2.0% vs . 6.1%; p  = 0.342). Compared with surgical tracheostomy, PDTS demonstrated a lower observed complication rate (4.0% vs . 23.9%; p   <  0.001), although this comparison was confounded by baseline differences. Bronchoscopic inspection prompted guidewire repositioning in 5% of cases.

Trans-isthmic PDTS is common and, within this preselected cohort, was not associated with a higher observed rate of early complications. Pre-procedural ultrasound appears valuable for anatomical assessment and patient selection, while the additional benefit of intra-procedural ultrasound guidance in reducing early complications was not demonstrated. These findings are exploratory and should be confirmed in larger studies.

The study was registered with ClinicalTrials.gov (NCT 05792098; March 30, 2023).