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Trial registered on ANZCTR


Registration number
ACTRN12610000139077
Ethics application status
Approved
Date submitted
8/02/2010
Date registered
10/02/2010
Date last updated
11/07/2012
Type of registration
Prospectively registered

Titles & IDs
Public title
The influence of differing inspired oxygen concentrations on platelet function in a model of lower limb ischaemic reperfusion injury
Scientific title
A trial of patients with a lower limb arterial tournique and whether an increase in inspired oxygen concentration at the time of reperfusion has any effect on platelet activation, as assessed by flow cytometry and thromboelastography
Secondary ID [1] 1394 0
None
Universal Trial Number (UTN)
Trial acronym
SLIPPER
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Ischaemic reperfusion injuries 256783 0
Condition category
Condition code
Blood 256928 256928 0 0
Clotting disorders
Anaesthesiology 256929 256929 0 0
Anaesthetics
Anaesthesiology 256930 256930 0 0
Other anaesthesiology

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
After randomization to a fractional inspired oxygen concentration of either 0.3, 0.5 or 0.8, the fractional inspired oxygen concentration is altered accordingly from 0.3 at the time of reperfusion. This is achieved by altering oxygen concentration on the ventilator. This is a one off treatment started 10 minutes before tourniquet release and continued until 24 hours after tourniquet release.
Intervention code [1] 255987 0
Treatment: Other
Comparator / control treatment
Keeping the fractional inspired oxygen concentration at 0.3 at the time of reperfusion. This is a one off treatment started 10 minutes before tourniquet release and continued until 24 hours after tourniquet release.
Control group
Dose comparison

Outcomes
Primary outcome [1] 257803 0
Change in platelet activation as assessed by flow cytometry (degree of change unknown)
Timepoint [1] 257803 0
pre induction, 10 mins pre tourniquet deflation, immediately pre tourniquet deflation, 5 mins post tourniquet, 30 mins and 24 hours post tourniquet deflation
Secondary outcome [1] 263218 0
Change in platelet activation as assessed by thromboelastography (degree of change unknown)
Timepoint [1] 263218 0
pre induction, 10 mins pre tourniquet deflation, immediately pre tourniquet deflation, 5 mins post tourniquet, 30 mins and 24 hours post tourniquet deflation

Eligibility
Key inclusion criteria
1. Adult patients undergoing lower limb surgery that requires the use of a tourniquet for more than 45 minutes
2. American Society of Anaesthesiology (ASA) grade 1 or 2
Minimum age
18 Years
Maximum age
80 Years
Gender
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
1. Patients taking any antiplatelet medication 2. Confirmed coagulation disorder (pathological or drug induced) 3. Platelet count less then 80 x 109/l 4. Blood urea greater than 8.0 mmol/L 5. Systemic infection 6. Confirmed systemic Inflammatory diseases 7. Documented pregnancy 8. Documented malignancy 9. Trauma other than the ipsilateral lower limb 10. Multiple tourniquet episodes 11. Likely intraoperative O2 requirement > 30%

Study design
Purpose of the study
Treatment
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Identified from theatre lists. Written informed consent as per ethical guidelines. Allocation concealment by sealed opaque envelopes. Patients blinded to intervention.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Random number generator using computerised sequence generation
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?



Intervention assignment
Parallel
Other design features
Phase
Not Applicable
Type of endpoint(s)
Safety
Statistical methods / analysis

Recruitment
Recruitment status
Not yet recruiting
Date of first participant enrolment
Anticipated
Actual
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)

Funding & Sponsors
Funding source category [1] 256490 0
Charities/Societies/Foundations
Name [1] 256490 0
Royal Perth Hospital Medical Research Fundation
Address [1] 256490 0
Royal Perth Hospital, Wellington street Campus, Perth 6000 WA
Country [1] 256490 0
Australia
Primary sponsor type
Hospital
Name
Royal Perth Hospital
Address
Royal Perth Hospital, Wellington street Campus, Perth 6000 WA
Country
Australia
Secondary sponsor category [1] 255803 0
None
Name [1] 255803 0
Address [1] 255803 0
Country [1] 255803 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 258541 0
Royal Perth Ethics Committee
Ethics committee address [1] 258541 0
Royal Perth Hospital, Wellington street Campus, Perth 6000 WA
Ethics committee country [1] 258541 0
Australia
Date submitted for ethics approval [1] 258541 0
Approval date [1] 258541 0
08/02/2010
Ethics approval number [1] 258541 0
EC2009/127

Summary
Brief summary
Evidence exists that surgery conducted with the use of a tourniquet results in blood being more prone to clotting. This phenomena starts whilst the tourniquet is inflated and increases when the tourniquet is deflated. Platelets are thought to be central to this process. Activation of the platelets may in part be due to products produced by the oxygen deprived tissue secondary to the use of the tourniquet. Some evidence exists that these products can be modified by altering the concentration of inspired oxygen at the time of reperfusion. However, whether altering the inspired concentration of oxygen influences platelet function remains unexplored. We plan to investigate whether changes in the inspired oxygen concentration alter platelet function in a model of ischaemic reperfusion injury. This is of clinical interest because ischaemic reperfusion injuries are encountered commonly in surgical practice. Examples include revascularisation of limbs in vascular surgery, organ transplantation, crush injuries etc. Maintenance of normal blood clotting is vital to clinical outcome.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 30817 0
Address 30817 0
Country 30817 0
Phone 30817 0
Fax 30817 0
Email 30817 0
Contact person for public queries
Name 14064 0
Dr Manuel Wenk
Address 14064 0
Department of Anaesthesia and Pain Medicine
Royal Perth Hospital,
Wellington Street Campus,
Perth 6000
WA
Country 14064 0
Australia
Phone 14064 0
+61 8 9224 1036
Fax 14064 0
Email 14064 0
manuel.wenk@health.wa.gov.au
Contact person for scientific queries
Name 4992 0
Dr Manuel Wenk
Address 4992 0
Department of Anaesthesia and Pain Medicine
Royal Perth Hospital,
Wellington Street Campus,
Perth 6000
WA
Country 4992 0
Australia
Phone 4992 0
+61 8 9224 1036
Fax 4992 0
Email 4992 0
manuel.wenk@health.wa.gov.au

No information has been provided regarding IPD availability
Summary results
No Results