NCT07856641 · The University of Texas Health Science Center, Houston
Circadian Variation of Anti-Factor Xa in Hospitalized Trauma Patients
What this study is about
The purpose of this study is to determine whether a circadian rhythm exists in anti-FXa levels and AT3 activity in hospitalized trauma patients receiving low-molecular-weight heparin (LMWH) chemoprophylaxis
View original scientific description
The purpose of this study is to determine whether a circadian rhythm exists in anti-FXa levels and AT3 activity in hospitalized trauma patients receiving low-molecular-weight heparin (LMWH) chemoprophylaxis
Primary outcome measures
Change in anti-factor Xa (anti-FXa) levels
Time frame: 4 hours after the 3rd LMWH dose (T0), then every 6 hours (T6, T12, T18)
Change in Antithrombin III (AT3) activity
Time frame: 4 hours after the 3rd LMWH dose (T0), then every 6 hours (T6, T12, T18)
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- Inpatient admission for acute traumatic injury ≥72 hours
- Prescribed LMWH subcutaneous for VTE chemoprophylaxis
Exclusion criteria
- Brain hemorrhage or non-survivable injury
- Chronic Kidney disease ≥ 3b estimated Glomerular Filtration Rate (eGFR) less than 30 interferes with coagulation
- Chronic liver failure •-Acute stimulant use of cocaine and methamphetamine
- Active VTE or ongoing anticoagulation at admission
- History of coagulopathy or inherited bleeding disorders
- Chronic alcohol as defined as a documented diagnosis of alcohol use disorder or alcohol consumption exceeding established risk thresholds (men \>14 drinks/week; women \>7 drinks/week) within the prior 3-6 months
- Unmanaged psychiatric conditions as defined as diagnosed psychiatric disorder with evidence of inadequate or no active treatment or documented poor symptom control
- Neurologic injury involving hypothalamic or circadian regulatory centers
Where
- Houston, Texas
Collaborators
Sigma Theta Tau International Grant; Jerold B. Katz Endowment Fund
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Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced Oct 2, 2026 · Source of record for eligibility and locations