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Trial registered on ANZCTR


Registration number
ACTRN12618000356268
Ethics application status
Approved
Date submitted
12/01/2018
Date registered
9/03/2018
Date last updated
9/03/2018
Type of registration
Prospectively registered

Titles & IDs
Public title
Modelling risk of early post-operative complications for patients undergoing major lower limb amputation
Scientific title
Modelling risk of in-hospital mortality and other early post-operative complications for patients undergoing major lower limb amputation entered into the United Kingdom National Vascular Registry
Secondary ID [1] 293739 0
None
Universal Trial Number (UTN)
U1111-1207-3753
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Lower limb amputation 306106 0
Condition category
Condition code
Cardiovascular 305234 305234 0 0
Diseases of the vasculature and circulation including the lymphatic system
Musculoskeletal 305235 305235 0 0
Other muscular and skeletal disorders
Surgery 305705 305705 0 0
Other surgery

Intervention/exposure
Study type
Observational
Patient registry
True
Target follow-up duration
30
Target follow-up type
Days
Description of intervention(s) / exposure
Patients undergoing major lower limb amputation who are entered into the United Kingdom National Vascular Registry
Duration of observation: from time of surgery until discharge from hospital.
Intervention code [1] 299991 0
Not applicable
Comparator / control treatment
No control group
Control group
Uncontrolled

Outcomes
Primary outcome [1] 304388 0
In-hospital mortality, as entered into the registry by the hospital or unit responsible for the patient's care, and validated by the surgeon responsible for the patient's care.
Timepoint [1] 304388 0
The registry collects this outcome prospectively from the hospital or unit responsible for the patient's care and this is validated by the surgeon responsible for the patient's care. We will assess this retrospectively from the registry at the date of study commencement.
Secondary outcome [1] 341791 0
Length of post-operative stay in hospital, as entered into the registry by the hospital or unit responsible for the patient's care, and validated by the surgeon responsible for the patient's care.
Timepoint [1] 341791 0
The registry collects this outcome prospectively from the hospital or unit responsible for the patient's care and this is validated by the surgeon responsible for the patient's care. We will assess this retrospectively from the registry at the date of study commencement.
Secondary outcome [2] 341792 0
Return to theatre during primary admission, as entered into the registry by the hospital or unit responsible for the patient's care, and validated by the surgeon responsible for the patient's care.
Timepoint [2] 341792 0
The registry collects this outcome prospectively from the hospital or unit responsible for the patient's care and this is validated by the surgeon responsible for the patient's care. We will assess this retrospectively from the registry at the date of study commencement.
Secondary outcome [3] 341793 0
Re-admission to a higher level of care during primary admission, as entered into the registry by the hospital or unit responsible for the patient's care, and validated by the surgeon responsible for the patient's care.
Timepoint [3] 341793 0
The registry collects this outcome prospectively from the hospital or unit responsible for the patient's care and this is validated by the surgeon responsible for the patient's care. We will assess this retrospectively from the registry at the date of study commencement.
Secondary outcome [4] 341794 0
Post-operative complications during primary admission, as entered into the registry by the hospital or unit responsible for the patient's care, and validated by the surgeon responsible for the patient's care.
Timepoint [4] 341794 0
The registry collects this outcome prospectively from the hospital or unit responsible for the patient's care and this is validated by the surgeon responsible for the patient's care. We will assess this retrospectively from the registry at the date of study commencement.

Eligibility
Key inclusion criteria
Patients undergoing major lower limb amputation entered into the United Kingdom National Vascular Registry between January 1st 2014 and December 31st 2016
Minimum age
18 Years
Maximum age
No limit
Gender
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
Patients not entered into the database, or not undergoing major lower limb amputation during the study period.

Study design
Purpose
Natural history
Duration
Longitudinal
Selection
Defined population
Timing
Retrospective
Statistical methods / analysis
Logistic regression analysis will be used to develop models for the outcomes using pre-operative and peri-operative predictors. Information Criterion analysis will be used to select predictors in order to generate a parsimonious model which avoids over-fitting. Bootstrap methodology will then be used to assess performance of the model, and compare this to existing risk prediction models, as well as comparing the results obtained using complete case analysis with those obtained using multiple imputation, to assess the impact of the method of handling missing data on the results. Missing data will be handled using both complete case analysis and multiple imputation with chained equations.

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 outside Australia
Country [1] 9474 0
United Kingdom
State/province [1] 9474 0

Funding & Sponsors
Funding source category [1] 298352 0
Government body
Name [1] 298352 0
Aneurin Bevan University Health Board
Address [1] 298352 0
Clinical Research and Innovation Centre
St Woolos Hospital
Block C
Stow Hill
Newport, South Wales
NP20 4SZ
Country [1] 298352 0
United Kingdom
Primary sponsor type
Government body
Name
Aneurin Bevan University Health Board
Address
Clinical Research and Innovation Centre
St Woolos Hospital
Block C
Stow Hill
Newport, South Wales
NP20 4SZ
Country
United Kingdom
Secondary sponsor category [1] 297474 0
Individual
Name [1] 297474 0
Christopher P Twine
Address [1] 297474 0
Vascular Institute
Royal Gwent Hospital
Cardi Road
Newport
NP20 2UB
Country [1] 297474 0
United Kingdom

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 299347 0
Wales REC 3
Ethics committee address [1] 299347 0
Health and Care Research Wales Support Centre
Castlebridge 4
15-19 Cowbridge Road East
Cardiff CF11 9AB
Ethics committee country [1] 299347 0
United Kingdom
Date submitted for ethics approval [1] 299347 0
17/01/2018
Approval date [1] 299347 0
29/01/2018
Ethics approval number [1] 299347 0
16/WA/0353

Summary
Brief summary
The appropriate counselling of patients about peri- and post-operative risks is an essential part of the process of consent to surgery. Patients undergoing major lower limb amputation (MLLA) are a high risk group, with 30-day mortality rates of around 10%, making MLLA the highest risk common Vascular Surgery operation other than ruptured abdominal aortic aneurysm (AAA) repair: higher than elective open AAA repair (3.0%) or lower limb bypass (3.0%). Recent UK court rulings about patient consent have brought this issue to the fore for both patients and surgeons alike. This is an evolving area, but current advice is now that ‘surgeons are required to engage in a consenting process tailored to the individual patient with detailed, accurate and realistic explanations of the pros and cons of surgery.’ In procedures such as MLLA, where individual risk clearly varies widely between patients, it is important therefore to be able to quantify risks as accurately as possible. The issue of risk prediction for high-risk surgical procedures is also important in light of the advent of surgeon-specific outcome publication in the United Kingdom. In order to reduce the likelihood that high risk patients are denied procedures which they might otherwise have chosen to undergo as a result of a surgeon’s unwillingness to run the risk of poor outcomes publication, it is essential to be able to appropriately risk adjust these national audits.
Using existing, prospectively collected data from the United Kingdom National Vascular Registry, we will develop models to predict the chances of complications after surgery including death in hospital, prolonged stay in hospital, need to go back to the operating theatre for another operation, post-operative chest infection and post-operative heart problems.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 80134 0
Mr Christopher P Twine
Address 80134 0
Vascular Institute
Royal Gwent Hospital
Cardiff Road
Newport
NP20 2UB
Country 80134 0
United Kingdom
Phone 80134 0
+44 1633 234124
Fax 80134 0
Email 80134 0
christopher.twine@wales.nhs.uk
Contact person for public queries
Name 80135 0
Dr Graeme Ambler
Address 80135 0
Division of Population Medicine
Cardiff University School of Medicine
3rd Floor Neuadd Meirionnydd
Heath Park
Cardiff
CF14 4YS
Country 80135 0
United Kingdom
Phone 80135 0
+44 1633 234124
Fax 80135 0
Email 80135 0
amblergk@cardiff.ac.uk
Contact person for scientific queries
Name 80136 0
Dr Graeme Ambler
Address 80136 0
Division of Population Medicine
Cardiff University School of Medicine
3rd Floor Neuadd Meirionnydd
Heath Park
Cardiff
CF14 4YS
Country 80136 0
United Kingdom
Phone 80136 0
+44 1633 234124
Fax 80136 0
Email 80136 0
amblergk@cardiff.ac.uk

No data has been provided for results reporting
Summary results
Not applicable