A randomised clinical trial to compare the AV impulse foot pump with low molecular weight Heparin in the prevention of deep vein thrombosis after total knee replacement

ISRCTN	ISRCTN51028168
DOI	https://doi.org/10.1186/ISRCTN51028168
Protocol serial number	R/41/1.97/Warw
Sponsor	NHS R&D Regional Programme Register - Department of Health (UK)
Funder	NHS Executive South West (UK)

Submission date: 23/01/2004
Registration date: 23/01/2004
Last edited: 22/02/2008

Recruitment status: No longer recruiting
Overall study status: Completed
Condition category: Surgery

Prospectively registered

Protocol

Statistical analysis plan

Results

Individual participant data

Plain English summary of protocol

Not provided at time of registration

Contact information

Mr David Warwick
Scientific

Southampton University Hospitals NHS Trust
Department of Orthopaedic Surgery
Southampton General Hospital
Tremona Road
Southampton
SO16 6YD
United Kingdom

Phone	+44 (0)23 8079 6245
Email	davidwarwick@handsurgery.co.uk

Study information

Primary study design	Interventional
Study design	Randomised controlled trial
Secondary study design	Randomised controlled trial
Scientific title
Study objectives	What is the relative effectiveness (against deep vein thrombosis [DVT]), safety and cost of Low Molecular Weight Heparin and the AV Impulse Foot Pump after total knee replacement surgery?
Ethics approval(s)	Our study had the approval of the local Medical Research and Ethics Committee.
Health condition(s) or problem(s) studied	Total knee replacement
Intervention	Enoxaparin (40 mg) was administered, subcutaneously, 12 hours before surgery (in accordance with the UK licence) and every 24 hours thereafter until discharge from hospital. The slippers for the foot pump were applied in the recovery room and the controller was then engaged. The foot pump was then used whenever the patient was not weight-bearing until discharge from hospital. The patient lay in bed with the legs parallel to the floor. The controller activated the pump every 20 seconds at a pressure of 130 mmHg for a period of one second.
Intervention type	Drug
Phase	Not Specified
Drug / device / biological / vaccine name(s)	Enoxaparin
Primary outcome measure(s)	Frequency of DVT as shown by the results of ipsilateral ascending venography between the sixth and eighth postoperative days.
Key secondary outcome measure(s)	1. Perioperative blood loss: a single drain was used routinely and blood loss was derived from a summation of intraoperative blood loss and postoperative drainage at 36 hours 2. Haemoglobin and haematocrit: measured before operation, on the second day after surgery and just before discharge 3. Blood loss index: transfusion requirements of the patients were noted. We recorded whether or not the patient had bruising or oozing from the site of the wound on the fourth and seventh postoperative days. 4. Swelling: assessed by measuring the circumference of the thigh and calf at 10 cm above and below the joint, respectively on the fourth and seventh postoperative days. The level was marked by an indelible pen to maintain consistency. 5. Knee flexion: measured active knee flexion with a goniometer on the fourth and seventh postoperative days. The soft-tissue side-effects were assessed in an open-label manner as it was apparent whether or not the patient was using a foot pump.
Completion date	01/02/1999

Eligibility

Participant type(s)	Patient
Age group	Not Specified
Sex	Not Specified
Target sample size at registration	229
Key inclusion criteria	Patients scheduled for unilateral primary total knee replacement at the Avon Orthopaedic Centre.
Key exclusion criteria	1. Refusal of consent 2. Long-term warfarin therapy for pre-existing cardiac or cerebral disease 3. A bleeding tendency 4. Painful joints or wounds in the feet which would preclude the use of the foot pump
Date of first enrolment	01/08/1997
Date of final enrolment	01/02/1999

Locations

Countries of recruitment

United Kingdom
England

Study participating centre

Southampton University Hospitals NHS Trust

Southampton
SO16 6YD
United Kingdom

Results and Publications

Individual participant data (IPD) Intention to share	No
IPD sharing plan summary	Not provided at time of registration
IPD sharing plan

Study outputs

Output type	Details	Date created	Date added	Peer reviewed?	Patient-facing?
Results article	Results	01/04/2002		Yes	No