Investigating blood clots and risk factors in children with congenital heart disease undergoing surgery with central lines.

Central Venous Access Device (CVAD) Associated Thrombosis in Neonates and Infants with Congenital Heart Disease This is an observational study designed to identify the incidence of central venous access device (CVAD)-associated thrombosis in neonates and infants undergoing cardiac surgery for congenital heart disease. The study aims to evaluate the modifiable and non-modifiable risks for the development of CVAD-associated thrombosis. Procedures/Activities: 1. Ultrasound Monitoring: All CVAD insertions are completed under ultrasound (USS) guidance to monitor for potential thrombosis. Dedicated ultrasound scans will be performed on insertion and day 4 post-CVAD insertion, either with the CVAD still in place or removed. Follow-up ultrasounds may occur at 12 months for infants with diagnosed thrombosis. 2. Imaging: The neck CVAD insertion sites (internal jugular vein, subclavian vein, and brachiocephalic vein) and groin insertion sites (common femoral vein, external iliac vein, and common iliac vein) will be documented using high-frequency duplex ultrasound. 3. Blinded Ultrasound: On day 4 post-insertion, a blinded ultrasound of the CVAD and adjacent vessel will be performed. Results will not be given to the clinical team unless needed for the patient's care. If thrombosis is identified, results will be discussed with parents at discharge, along with appropriate counseling. 4. Thrombosis Resolution Follow-up: For infants with diagnosed CVAD-associated venous thrombosis, follow-up ultrasounds will be scheduled approximately 12 months after the initial CVAD insertion to assess thrombus size, type, and resolution. Mode of Delivery: - Face-to-face monitoring and follow-up will occur within Queensland Children’s Hospital (QCH), specifically in the cardiac ward, PICU, and medical imaging departments. - Ultrasound imaging will be done in the patient’s hospital bed or in the medical imaging department, depending on patient mobility. Duration: The intervention (ultrasound monitoring) will be administered at specified intervals during and post-surgery: - Initial ultrasound on insertion or within 4 days of CVAD insertion. - Blinded 4 day ultrasound - Follow-up ultrasound approximately 12 months post-CVAD insertion for patients with thrombosis. Intervention Providers: - Paediatric sonographers with expertise in cardiac and vascular ultrasound will perform imaging. - Anaesthetists will assist with intraoperative ultrasound guidance during CVAD insertion. Fidelity and Adherence: Intervention fidelity will be maintained through the use of a standardised ultrasound protocol. All sonographers will complete dedicated worksheets, and images will be reviewed and reported by a radiologist. Safeguards are in place to ensure prompt action if thrombosis is detected.