Development and Validation of an Ultrasound-Based Difficult Cannulation Risk Score

Overview

Ultrasound-guided internal jugular vein (IJV) catheterization is widely used in critically ill patients. Despite ultrasound guidance, difficult catheterization and first-pass failure remain clinically important and may increase the risk of mechanical complications. Pre-procedural characteristics of the IJV, its anatomical relationship with the common carotid artery (CCA), head rotation, and operator experience may influence procedural success. The ROTATE-ICU study is a prospective observational cohort study designed to investigate pre-procedural ultrasound and clinical predictors of difficult IJV catheterization in critically ill adults. Consecutive adult intensive care unit patients undergoing ultrasound-guided IJV central venous catheterization will undergo standardized pre-procedural ultrasound assessment. IJV anterior-posterior diameter, skin-to-vessel depth, IJV position relative to the CCA, head rotation angle, operator experience, and relevant clinical and procedural characteristics will be recorded. The primary objective is to develop and internally validate a clinical prediction model for cannulation difficulty and first-pass cannulation outcome. Secondary objectives include evaluating the relationship between head rotation and IJV morphology and describing the association between complete IJV collapse and procedural outcomes. The planned enrollment is 150 participants.

Central venous catheterization is a common procedure in critically ill patients. Ultrasound guidance improves procedural safety; however, first-pass failure and difficult catheterization remain common and may lead to repeated punctures, prolonged procedure time, arterial puncture, hematoma, and other mechanical complications. Anatomical characteristics of the internal jugular vein (IJV), particularly vessel diameter and its positional relationship with the common carotid artery (CCA), may influence cannulation difficulty. Operator experience and head position may also modify procedural success. Nevertheless, these factors have rarely been integrated into a prospective pre-procedural prediction strategy in critically ill patients. ROTATE-ICU is a prospective, single-center observational cohort study enrolling consecutive adult intensive care unit patients undergoing ultrasound-guided IJV central venous catheterization. Before catheterization, patients will undergo standardized ultrasound examination with measurement of the IJV anterior-posterior diameter and skin-to-vessel depth and classification of the IJV position relative to the CCA. Head rotation angle and operator experience will also be recorded. Procedural outcomes including first-pass cannulation success, number of skin punctures, procedure duration, need for site change, and mechanical complications will be prospectively documented. Difficult catheterization will be defined using a composite of multiple punctures, prolonged procedure duration, and/or need for access-site change. The study aims to determine independent pre-procedural predictors of cannulation outcome and to develop a clinically applicable ultrasound-based risk prediction model. Model discrimination and calibration will be assessed and internal validation will be performed. A planned cohort of 150 participants will be enrolled. No intervention is assigned by the study protocol, and all catheterization decisions and clinical management will remain at the discretion of the treating clinical team.