NCT02477072

Brief Summary

Hypothesis: Optimal anticoagulation defined as an Activated Clotting Time (ACT) of 300 to 350 seconds obtained by weight-adjusted doses of unfractionated heparin (UFH) will improve the hemostatic environment downstream from the vascular clamp, provide better blood flow in the distal bed following peripheral revascularization surgery. Objectives: This study is designed to assess the effects of an optimized regimen of UFH on the hemostatic environment downstream from the vascular clamp in major vascular surgery.

Trial Health

87
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
32

participants targeted

Target at P25-P50 for not_applicable

Timeline
Completed

Started Sep 2015

Shorter than P25 for not_applicable

Geographic Reach
1 country

1 active site

Status
completed

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

First Submitted

Initial submission to the registry

June 16, 2015

Completed
6 days until next milestone

First Posted

Study publicly available on registry

June 22, 2015

Completed
2 months until next milestone

Study Start

First participant enrolled

September 1, 2015

Completed
4 months until next milestone

Primary Completion

Last participant's last visit for primary outcome

January 1, 2016

Completed
Same day until next milestone

Study Completion

Last participant's last visit for all outcomes

January 1, 2016

Completed
Last Updated

January 12, 2016

Status Verified

January 1, 2016

Enrollment Period

4 months

First QC Date

June 16, 2015

Last Update Submit

January 11, 2016

Conditions

Peripheral Revascularisation

Outcome Measures

Primary Outcomes (1)

  • Anticoagulation upstream and downstream from the clamp

    Adequacy of anticoagulation upstream and downstream from the clamp will be assessed with the ACT and the thromboelastogram.

    From induction of anesthesia until 30 minutes following the return of normal blood flow

Secondary Outcomes (6)

  • Peripheral blood flow

    Before surgery and following surgery in the recovery room - on Day 1

  • Occurence of any new revascularization surgery as a measure of safety and efficacy

    From surgery until thirty days following surgery

  • Occurrence of arrhythmia as a measure of safety

    From surgery until discharge from the hospital - approximately 4 days

  • Quantity of blood lost during surgery as a measure of safety

    At the end of surgery - on Day 1

  • Number of red blood cells transfusions administered as a measure of safety

    From surgery until discharge from the hospital - approximately 4 days

  • +1 more secondary outcomes

Study Arms (3)

Fixed heparin dose (general anesthesia)

ACTIVE COMPARATOR

Study subjects will be randomized to receive a fixed dose of 5000 units of heparin administered intravenously 2 minutes prior to vascular clamping and blood flow interruption. A subsequent dose of heparin will be administered if requested by the surgeon following a visual assessment of the anticoagulation in the surgical field. Anticoagulation will be monitored at different time points during surgery using ACT and TEG. Peripheral blood flow will be assessed prior and after surgery using the ankle-brachial index and toe-brachial index.

Procedure: ACTProcedure: TEGProcedure: Ankle-brachial indexProcedure: Toe-brachial indexDrug: Heparin

Weight-adjusted doses of heparin

EXPERIMENTAL

Study subjects will be randomized to receive 100 units of heparin per kilogram administered intravenously 2 minutes before vascular clamping and blood flow interruption. Subsequent doses of heparin will be administered to maintain the ACT between 300 and 350 seconds at all times during vascular clamping. Anticoagulation will be monitored at different time points during surgery using ACT and TEG. Peripheral blood flow will be assessed prior and after surgery using the ankle-brachial index and toe-brachial index.

Procedure: ACTProcedure: TEGProcedure: Ankle-brachial indexProcedure: Toe-brachial indexDrug: Heparin

Fixed heparin dose (regional anesthesia)

ACTIVE COMPARATOR

For safety reasons, study subjects under regional anesthesia will automatically be assigned to this group and will receive a fixed dose of 5000 units of heparin administered intravenously 2 minutes prior to vascular clamping and blood flow interruption. A subsequent dose of heparin will be administered if requested by the surgeon following a visual assessment of the anticoagulation in the surgical field. Anticoagulation will be monitored at different time points during surgery using ACT and TEG.

Procedure: ACTProcedure: TEGDrug: Heparin

Interventions

ACTPROCEDURE

Blood samples for ACT will be collected following induction of anesthesia, 30 minutes after heparin administration, and on arrival in the recovery room.

Also known as: Activated clotting time
Fixed heparin dose (general anesthesia)Fixed heparin dose (regional anesthesia)Weight-adjusted doses of heparin
TEGPROCEDURE

Blood samples for TEG will be collected following induction of anesthesia, 30 minutes after heparin administration, and on arrival in the recovery room.

Also known as: Thromboelastography
Fixed heparin dose (general anesthesia)Fixed heparin dose (regional anesthesia)Weight-adjusted doses of heparin
Ankle-brachial indexPROCEDURE

Peripheral blood flow will be assessed prior and after surgery using the ankle-brachial and toe-brachial indexes.

Fixed heparin dose (general anesthesia)Weight-adjusted doses of heparin
Toe-brachial indexPROCEDURE

Peripheral blood flow will be assessed prior and after surgery using the ankle-brachial and toe-brachial indexes.

Fixed heparin dose (general anesthesia)Weight-adjusted doses of heparin
HeparinDRUG

Heparin doses will be administered according to the assigned group.

Also known as: Unfractionated heparin
Fixed heparin dose (general anesthesia)Fixed heparin dose (regional anesthesia)Weight-adjusted doses of heparin

Eligibility Criteria

Age18 Years - 90 Years
Sexall
Healthy VolunteersNo
Age GroupsAdult (18-64), Older Adult (65+)

You may qualify if:

  • Patients undergoing elective revascularization surgery
  • American Society of Anesthesiologists (ASA) physical status l-lll inclusive

You may not qualify if:

  • Known or suspected allergy to heparin or protamine
  • Contraindication to heparin or protamine
  • Known or suspected coagulopathy
  • Current anticoagulation or residual effect of anticoagulants, antiplatelet agents, except aspirin

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

Centre Hospitalier de l'Université de Montréal (CHUM-Hôtel-Dieu)

Montreal, Quebec, H2W 1T8, Canada

Location

Related Publications (1)

  • Roy M, Todorov A, Ruel M, Elkouri S, Hardy JF. Anticoagulation Obtained below the Arterial Clamp Using a Single Fixed Bolus of Heparin in Vascular Surgery: A Pilot Study. Ann Vasc Surg. 2018 Jul;50:242-248. doi: 10.1016/j.avsg.2017.11.060. Epub 2018 Feb 23.

    PMID: 29481926DERIVED

MeSH Terms

Interventions

ThrombelastographyHeparin

Intervention Hierarchy (Ancestors)

Blood Coagulation TestsHematologic TestsClinical Laboratory TechniquesDiagnostic Techniques and ProceduresDiagnosisInvestigative TechniquesGlycosaminoglycansPolysaccharidesCarbohydrates

Study Officials

  • Hardy Jean-François, MD, FRCPC

    Centre hospitalier de l'Université de Montréal (CHUM)

    PRINCIPAL INVESTIGATOR

Study Design

Study Type
interventional
Phase
not applicable
Allocation
RANDOMIZED
Masking
DOUBLE
Who Masked
PARTICIPANT, CARE PROVIDER
Purpose
TREATMENT
Intervention Model
PARALLEL
Sponsor Type
OTHER
Responsible Party
SPONSOR

Study Record Dates

First Submitted

June 16, 2015

First Posted

June 22, 2015

Study Start

September 1, 2015

Primary Completion

January 1, 2016

Study Completion

January 1, 2016

Last Updated

January 12, 2016

Record last verified: 2016-01

Locations

CA(1)