Contact Activation of Coagulation in Newly Inserted Central Venous Catheters

Not Applicable

Not yet recruiting

• Conditions: Central Venous Catheter; Coagulation; Coagulation Activation; Central Venous Catheter Complications

• Registration Number: NCT07014722
• Lead Sponsor: Thomas Kander

Brief Summary

A central venous catheter (CVC) is a thin plastic tube placed into one of the body's large veins, typically in the neck or near the clavicle. CVCs are crucial for administering medications, fluids, and secure blood samples. Although CVCs are an essential tool in healthcare, there are certain risks and complications associated with their use. CVCs can affect the body's coagulation system, potentially leading to the formation of blood clots at the site of the catheter. This can result in serious complications, and in some cases, increased morbidity and mortality. Despite the known risk of blood clot formation with catheter use, it is still do not fully understand why clots occur or how a newly inserted catheter affects the coagulation system.

The aim of this randomized controlled trial is to compare four different central venous catheters and their impact on the coagulation system.

Eighty patients ≥18 years of age, who require a CVC and agree to participate in the study will be randomly assigned to one of the four predetermined, commonly used, central venous catheters. Two blood samples will be taken from the newly inserted catheter. The first blood sample (Sample 1) will be collected within seconds after catheter insertion without pre-flushing the catheter with saline. The second blood sample (Sample 2) will be taken after the catheter has been flushed with saline, and the initial blood discarded. Samples 1 and 2 will then be analyzed to measure how the coagulation system is affected after contact with the inside surface of the CVC. The blood samples will also be compared between the different catheter types.

The study could provide valuable information on how the coagulation system is affected after catheter insertion. This knowledge could help improve preventive measures to reduce the risk of blood clot formation and ensure safer blood sampling for patients with venous catheters.

Detailed Description

This is a randomized controlled trial, designed to evaluate coagulation activation in response to four different commercially available central venous catheters (CVCs), all with similar internal surface areas. The study focuses on comparing changes in coagulation parameters, primarily clotting time (CT), measured using rotational thromboelastometry (ROTEM® NATEM), as well as additional ROTEM variables and standard coagulation markers.

Participants are included based on clinical need for central venous access, and are randomized using REDCap to receive one of four CVC types:

1. MERITMEDICAL Careflow™ Two-Lumen Catheter (7 Fr, 150 mm, polyurethane, OD 2.4 mm)

2. ARROW Two-Lumen Catheter (7 Fr, 160 mm, polyurethane, OD 2.5 mm)

3. ARROWg+ard Blue Plus® Two-Lumen Catheter (8 Fr, 160 mm, polyurethane, OD 2.8 mm, chlorhexidine/silver sulfadiazine coating)

4. Multicath 2 Expert UP Two-Lumen Catheter (7.5 Fr, 160 mm, polyurethane shaft embedded with silver ions, OD 2.5 mm)

Blood samples will be collected at two time points for each participant:

* Sample 1: Immediately after catheter insertion, before flushing

* Sample 2: After a standardized flush and discard protocol

All catheters will be inserted without pre-procedural filling with saline.

Blood will be collected into Vacuette® CTAD tubes (Greiner Bio-One, Kremsmünster, Austria) containing sodium citrate, theophylline, adenosine, and dipyridamole, designed for hemostatic testing. The tubes will be inverted eight times immediately after blood collection and kept at 37°C until processing. ROTEM® analysis will be performed within 3 hours of blood collection. After the ROTEM® analysis, the remaining blood will undergo centrifugation at 4000g for 15 minutes, and 600-700 µL of plasma from each sample will be transferred into cryotubes, which will be immediately frozen and stored at -80°C for further analysis.

Laboratory and ROTEM® Analyses

ROTEM® analyses will be performed on whole blood using recalcified non-activated thromboelastometry (NATEM), in accordance with the manufacturer's instructions. Each test will be run for 60 minutes, measuring the following variables:

Clotting Time (CT) - time to initial fibrin formation Clot Formation Time (CFT) - speed of thrombus development Alpha Angle (α-angle) - kinetics of clot formation Maximum Clot Firmness (MCF) - measure of final clot strength

Routine Plasma-Based Coagulation Assays:

Prothrombin Time-International Normalized Ratio (PT-INR) Activated Partial Thromboplastin Time (aPTT)

The following coagulation markers will also be assessed:

Factor VII (FVII) and Factor XII (FXII) Thrombin-Antithrombin Complex (TAT)

Study Timeline

• Study First Submitted: 2025-05-12
• Status Verified: 2025-06
• Study First Submitted QC: 2025-06-02
• Last Update Submitted: 2025-06-10
• Study First Posted: 2025-06-11
• Last Update Posted: 2025-06-13
• Study Start: 2025-09-01
• Primary Completion: 2025-12-30
• Study Completion: 2026-11-30

Recruitment & Eligibility

• Status: NOT_YET_RECRUITING
• Sex: All
• Target Recruitment: 80

Inclusion Criteria

Not provided

Exclusion Criteria

Not provided

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Primary Outcome Measures

Name	Time	Method
Change in ROTEM Clotting Time (CT) (seconds) between Sample 1 and Sample 2	Immediately after catheter insertion (Sample 1) and after flush and discard, within one hour (Sample 2)	The primary endpoint is the difference in clotting time (CT), measured using ROTEM NATEM, between two blood samples collected from each participant. Sample 1 is collected immediately after catheter insertion, and Sample 2 is collected after a standardized flush and discard procedure. The change in CT will be compared across the four catheter groups to evaluate differences in coagulation activation.

Secondary Outcome Measures

Name	Time	Method
Within catheter group change in Clotting Time (CT) (seconds) between Sample 1 and Sample 2	Immediately after catheter insertion (Sample 1) and after flush and discard, within one hour (Sample 2)	Within-catheter group changes in CT between Sample 1 and Sample 2 will be analyzed
Change in ROTEM Alpha Angle (α-angle) (degrees) between Sample 1 and Sample 2	Immediately after catheter insertion (Sample 1) and after flush and discard, within one hour (Sample 2)	The within-subject differences in α-angle between Sample 1 and Sample 2 will be analyzed and compared across the four catheter types. In addition, within-catheter group changes in α-angle between Sample 1 and Sample 2 will be analyzed
Change in ROTEM Clot Formation Time (CFT) (seconds) between Sample 1 and Sample 2	Immediately after catheter insertion (Sample 1) and after flush and discard, within one hour (Sample 2)	The within-subject differences in CFT between Sample 1 and Sample 2 will be analyzed and compared across the four catheter types. In addition within-catheter group changes in CFT between Sample 1 and Sample 2 will be analyzed
Change in ROTEM Maximum Clot Firmness (MCF) (mm) between Sample 1 and Sample 2	Immediately after catheter insertion (Sample 1) and after flush and discard, within one hour (Sample 2)	The within-subject differences in MCF between Sample 1 and Sample 2 will be analyzed and compared across the four catheter types. In addition, within-catheter group changes in MCF between Sample 1 and Sample 2 will be analyzed
Change in Prothrombin Time - International Normalized Ratio (PT-INR) (continous unitless variable) between Sample 1 and Sample 2	Immediately after catheter insertion (Sample 1) and after flush and discard, within one hour (Sample 2)	The within-subject differences in PT-INR between Sample 1 and Sample 2 will be analyzed and compared across the four catheter types. In addition, within-catheter group changes in PT-INR between Sample 1 and Sample 2 will be analyzed
Change in Activated Partial Thromboplastin Time (aPTT) (seconds) between Sample 1 and Sample 2	Immediately after catheter insertion (Sample 1) and after flush and discard, within one hour (Sample 2)	The within-subject differences in aPTT between Sample 1 and Sample 2 will be analyzed and compared across the four catheter types. In addition, within-catheter group changes in aPTT between Sample 1 and Sample 2 will be analyzed
Change in Factor VII Activity (FVII) (kIU/L) between Sample 1 and Sample 2	Immediately after catheter insertion (Sample 1) and after flush and discard, within one hour (Sample 2)	The within-subject differences in FVII between Sample 1 and Sample 2 will be analyzed and compared across the four catheter types. In addition, within-catheter group changes in FVII between Sample 1 and Sample 2 will be analyzed
Change in Factor XII Activity (FXII) (kIU/L) between Sample 1 and Sample 2	Time Immediately after catheter insertion (Sample 1) and after flush and discard, within one hour (Sample 2)	The within-subject differences in FXII between Sample 1 and Sample 2 will be analyzed and compared across the four catheter types. In addition, within-catheter group changes in FXII between Sample 1 and Sample 2 will be analyzed
Change in Thrombin-Antithrombin Complex Concentration (TAT) (mikrogr/L) between Sample 1 and Sample 2	Immediately after catheter insertion (Sample 1) and after flush and discard, within one hour (Sample 2)	The within-subject differences in TAT between Sample 1 and Sample 2 will be analyzed and compared across the four catheter types. In addition, within-catheter group changes in TAT between Sample 1 and Sample 2 will be analyzed

Trial Locations

Locations (1)

Skåne University Hospital Lund; 🇸🇪 Lund, Skåne, Sweden