We are updating the design of this site. Learn more.
Show more
ClinicalTrials.gov Menu

Patients Preference With Self-Injection: The PRISM Study

This study has been completed.
ClinicalTrials.gov Identifier:
First Posted: November 15, 2005
Last Update Posted: March 10, 2009
The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details.
St. Joseph's Health Care London
Information provided by:
McMaster University
The purpose of this study is to determine which short-acting blood thinner (low-molecular-weight heparin [Enoxaparin] or unfractionated heparin) is associated with less discomfort and bruising when given as a subcutaneous (under the skin) injection before and after a planned surgery or procedure in patients who temporarily stop warfarin.

Condition Intervention Phase
Bruises Drug: Unfractionated heparin Drug: Enoxaparin Phase 4

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)
Primary Purpose: Treatment
Official Title: THE PRISM Study-Low-Molecular-Weight Heparin Versus Unfractionated Heparin for Perioperative Bridging Anticoagulation: the Patient Preference for Self-Injection Study and Related Measurements

Resource links provided by NLM:

Further study details as provided by McMaster University:

Primary Outcome Measures:
  • The primary outcome measure is self-reported comfort score based on a visual analogue scale (VAS). Patients will complete a 10-point VAS. Patients will complete a VAS at the time of injection.

Secondary Outcome Measures:
  • On the day of the procedure, bruising at injection sites will be evaluated.
  • Patients will document in a diary each injection before and after the surgery or invasive procedure. On the day of surgery or procedure abdominal bruising measurement will be obtained. A digital photo will be take of the injection site.

Estimated Enrollment: 100
Study Start Date: October 2005
Estimated Study Completion Date: January 2007
Detailed Description:

Increasing Patient Comfort and Compliance: The Bridging Anticoagulation Clinic strives to provide the highest quality of care to patients who require temporary interruption of warfarin therapy. An important component of optimizing patient care is minimizing patient discomfort with perioperative administration of short-acting anticoagulants (LWMH or UFH) used for bridging therapy, which, in turn, may optimize patient compliance with this treatment. This issue is especially relevant for patients who are receiving out-of-hospital treatment with LMWH or UFH because about 85% of such patients will be taught to self-administer this medication. This study seeks to determine if there is less discomfort and bruising associated with self-injection of LMWH than with UFH.

Minimizing Injection Site Bruising: No studies, to our knowledge, have assessed the characteristics or clinical importance of bruising in patients receiving subcutaneous LMWH or UFH. Thus, there is no evidence to support any association between bruising and discomfort. To bridge this gap in knowledge, we will document each injection site during the course of the study and measure the amount of bruising observed using a standardized photographic methodology. Injection site bruising has the potential to cause medical problems if an injection site hematoma develops, which can become infected or can cause long-term discomfort.


Information from the National Library of Medicine

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.

Ages Eligible for Study:   18 Years and older   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

  1. Patient is receiving warfarin therapy with a target international normalized ratio (INR) of 2.0-3.5
  2. Patient requires temporary interruption of warfarin because of elective surgery or procedure.

Exclusion Criteria:

  1. History of allergy to heparin, including heparin-induced thrombocytopenia (HIT)
  2. Bridging anticoagulation with low molecular weight heparin (LMWH) or unfractionated heparin (UFH) not indicated
  3. Impaired cognitive function or language barrier
  4. Creatinine clearance < 30 ml/min
  5. Patient declines consent
  6. Patient is < 18 years of age.
  7. Patient is not willing and able to self inject.
  8. Patient has significant visual or hand motor impairment
  Contacts and Locations
Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT00253396

Canada, Ontario
St. Joseph's Healthcare
Hamilton, Ontario, Canada, L8N 4A6
Sponsors and Collaborators
Hamilton Health Sciences Corporation
St. Joseph's Health Care London
Principal Investigator: Co-Investigators Dr. James Douketis and Karen Woods RN McMaster University
  More Information


ClinicalTrials.gov Identifier: NCT00253396     History of Changes
Other Study ID Numbers: 05-2482
First Submitted: November 14, 2005
First Posted: November 15, 2005
Last Update Posted: March 10, 2009
Last Verified: May 2007

Keywords provided by McMaster University:
clinical trial
pain measurement
heparin, low-molecular-weight

Additional relevant MeSH terms:
Calcium heparin
Heparin, Low-Molecular-Weight
Fibrinolytic Agents
Fibrin Modulating Agents
Molecular Mechanisms of Pharmacological Action