Condition category
Circulatory System
Date applied
Date assigned
Last edited
Retrospectively registered
Overall trial status
Recruitment status
No longer recruiting
Publication status

Plain English Summary

Not provided at time of registration

Trial website

Contact information



Primary contact

Dr Deborah Cook


Contact details

St Joseph's Hospital
50 Charlton Ave East
Martha Building
Rm H327
L8N 4A6
+1 905 522 1155 ext. 35325

Additional identifiers

EudraCT number number


Protocol/serial number

MCT-78568; ACTRN12606000090516

Study information

Scientific title

Low molecular weight heparin (LMWH) (dalteparin) versus unfractionated heparin (UFH) for deep vein thrombosis (DVT) prevention: a randomised, concealed, stratified, placebo-controlled, blinded, parallel assignment trial



Study hypothesis

To evaluate the effect of low molecular weight heparin (LMWH) (dalteparin) versus unfractionated heparin (UFH) on the primary outcome of proximal leg deep vein thrombosis (DVT) diagnosed by compression ultrasound, and the secondary outcomes of pulmonary embolism (PE), bleeding, heparin-induced thrombocytopenia (HIT), and objectively confirmed venous thrombosis at any site.

Please note that this is a large-scale version of a previously registered pilot trial, 'PROphylaxis for ThromboEmbolism in Critical care Trial (PROTECT) pilot study' [ISRCTN54618366] (see This large-scale version of the previous PROTECT Trial has been registered separately as changes to two of the exclusion criteria and one follow-up ultrasound of the protocol have been made between the pilot study and this large-scale trial.

As of 09/03/2009 this record was updated to include the addition of the United States of America as a country of recruitment, and an amended end date; the initial anticipated end date at the time of registration was 01/12/2011. All other changes can be found under the above date of update.

Ethics approval

1. Canada: Research Ethics Board of McMaster University, Hamilton, Ontario on the 21st November 2005 and 21st November 2007 (ref: 05-2572)
2. Australia: Ethics Committee of Alfred Hospital on the 1st December 2003 (initially) (ref: 181/03) and on the 9th January 2006 (ref: 236/05)
3. Brazil: Comitê de Ética, Santa Casa de Misericordian de Porto Alegre Hospital on the 27th July 2006 (ref: 1368/06) and the Comissâo Nacional de Ética em Pesquisa (CONEP), Ministério da saúde on the 20th August 2007 (ref: 620/2007)
4. Saudi Arabia: Institutional Review Board of King Faisal Specialist Hospital and Research Centre on the 13th March 2006 (initially) (ref: RC(J)103E/27) and on the 24th October 2007 (ref: RC(J) 334M/28)

Added 09/03/2009:
5. USA: Rhode Island Hospital IRB gave approval in April 2008

Study design

Interventional, randomised, double blind (subject, caregiver, investigator and outcomes assessor), placebo-controlled, parallel assignment, safety/efficacy study

Primary study design


Secondary study design

Randomised controlled trial

Trial setting


Trial type


Patient information sheet

Not available in web format, please use the contact details below to request a patient information sheet


Critical illness, deep vein thrombosis


1. Drug: LMWH (dalteparin), 5,000 IU daily and placebo
2. Unfractionated heparin (UFH), 5,000 IU twice daily

The followup duration is to hospital discharge (which will vary for each patient).

Intervention type



Not Applicable

Drug names

Dalteparin, unfractionated heparin

Primary outcome measure

To evaluate the effect of LMWH (dalteparin) versus UFH on the primary outcome of proximal leg DVT diagnosed by compression ultrasound. Time frame: while in ICU to a maximum of 90 days.

Secondary outcome measures

To evaluate the effect of LMWH (dalteparin) versus UFH on the secondary outcomes of PE, bleeding, HIT, and objectively confirmed venous thrombosis at any site. Time frame: while in ICU to a maximum of 90 days.

Overall trial start date


Overall trial end date


Reason abandoned (if study stopped)


Participant inclusion criteria

1. Admission to Intensive Care Unit (ICU)
2. Men or women greater than or equal to 18 years of age
3. Actual body weight greater than or equal to 45 kg
4. Admission to ICU expected to be greater than or equal to 72 hours in duration

Participant type


Age group




Target number of participants


Participant exclusion criteria

1. Trauma, post-orthopedic surgery or post-neurosurgery patients
2. Uncontrolled hypertension (systolic greater than 180 mmHg or diastolic greater than 110 mmHg)
3. Major haemorrhage, haemorrhagic stroke, DVT or PE on admission or within last three months
4. Coagulopathy as defined by international normalised ratio (INR) greater than two times upper limit of normal [ULN], or partial thromboplastin time (PTT) greater than two times ULN
5. Thrombocytopenia defined as platelet count less than or equal to 75 x 10^9/L
6. Need for oral or intravenous or subcutaneous therapeutic anticoagulation
7. Receipt of greater than three days of UFH or LMWH in ICU
8. Contraindication to heparin (e.g., suspected HIT), blood products or pork products
9. Pregnant or lactating
10. Withdrawal of life support or limitation of life support
11. Current enrolment in this trial or a related trial
12. Lack of informed consent

Recruitment start date


Recruitment end date



Countries of recruitment

Australia, Brazil, Canada, Saudi Arabia, United States of America

Trial participating centre

St Joseph's Hospital
Hamilton, Ontario
L8N 4A6

Sponsor information


Hamilton Health Sciences (Canada)

Sponsor details

1200 Main Street West
L8N 3Z5

Sponsor type

Research organisation



Funder type

Research organisation

Funder name

Canadian Institutes of Health Research (CIHR) (Canada) - (ref: MCT-78568)

Alternative name(s)

Funding Body Type

Funding Body Subtype


Results and Publications

Publication and dissemination plan

Not provided at time of registration

Intention to publish date

Participant level data

Not provided at time of registration

Basic results (scientific)

Publication list

1. 2011 results in: (added 10/04/2019)
2. 2011 protocol in: (added 10/04/2019)
3. 2013 results in: (added 10/04/2019)
4. 2013 results in: (added 10/04/2019)
5. 2014 results in: (added 10/04/2019)
6. 2014 economic evaluation in: (added 10/04/2019)
7. 2015 results in: (added 10/04/2019)
8. 2016 results in: (added 10/04/2019)

Publication citations

Additional files

Editorial Notes

10/04/2019: Publication reference added.