Predictors of Post Operative Outcome in Peripheral Vascular Surgical Patients
Over 3000 people each year undergo bypass operations to their lower limbs, and these operations carry significant risks with approximately 1 in 20 of these people dying in hospital, and another 1 in 20 having a heart attack. The number of people having this type of procedure has grown over recent years, and the trend is predicted to continue. Due to this significant increase in the volume of these patients and the associated complications that occur with this surgery utilisation of more resources such as critical care is often needed. Assessment of these patients in order to stratify their risk of both dying and having significant complicatons aid in improving their care, allow better utilisation of scarce critical care resources, and also allow us to give patients informed consent. A high risk group in major abdominal surgery can be identified through a simple exercise test (cardiopulmonary exercise test) that looks at how the body uses oxygen, and also through a blood test that look at a hormone secreted by the heart. Vascular surgical patients are at risk for the development of major cardiac complications in the postoperative period but a system for appropriate preoperative risk stratifications has yet to be achieved.
Aims The aims of the project are to assess the feasibility of exercise testing this group of patients both with cycle and arm exercise, and to identify markers of outcome in this group. Identification of markers that can predict how patients will fair after surgery will allow for informed consent, better resource utilisation, and opportunities to attempt to modify outcomes.
Methodology This is a prospective observational study designed to test the hypothesis that a combination of cardiopulmonary exercise testing and blood tests provides prognostic value on outcome measures after surgery for lower limb revascularisation Subjects will have 2 exercise tests, one arm and one cycle, prior to surgery at their preoperative assessment appointment. From this these test we will measure how much work patients can do, how much oxygen they are able to use, and when the hear is unable to deliver enough oxygen to the cells. In addition they will have blood samples taken prior to the operation (brain naturetic peptide), and on days 1 and 3 (troponin I) after the operation to look at cardiac markers of damage. This data will be used to see if we can predict those patients that have both short and long term complications, and also to see whether the different forms of exercise testing are comparable, or if one type is superior.
Expected outcomes We expect that through a combination of exercise testing and blood test we will be able to identify patients at increased risk of complications after surgery. We also expected to find that arm exercise will be a more feasible and informative test that cycle exercise.
Implications Identification of a high risk group would allow appropriate strategies to be implemented to reduce risk, and allow better post-operative resource utilisation. This study will also allow a larger multicentre study to be adquarely powered and constructed.
|Study Design:||Observational Model: Cohort
Time Perspective: Prospective
|Official Title:||Prognostic Markers of Outcome in Patients Undergoing Infra-inguinal Revascularisation. A Prospective Observational Study.|
- 1 year all cause mortality [ Time Frame: 1 year ] [ Designated as safety issue: No ]
- 1 year major adverse cardiac event. [ Time Frame: 1 year ]
- Morbidity as measured by the Post operative morbidity survey [ Time Frame: 7 days ] [ Designated as safety issue: No ]
- major adverse cardiac event. [ Time Frame: participants will be followed for the duration of hospital stay, an expected median of 10 days ] [ Designated as safety issue: No ]
- 30 day all cause mortality. [ Time Frame: 30 day ] [ Designated as safety issue: No ]
- Correlation between anaerobic threshold on cycle and arm ergometry [ Designated as safety issue: No ]
- Correlation of peak oxygen consumption on cycle and arm ergometry [ Designated as safety issue: No ]
- Surgical post operative complications [ Time Frame: participants will be followed for the duration of hospital stay, an expected median of 10 days ] [ Designated as safety issue: No ]participants will be followed for the duration of hospital stay, an expected median of 10 days
- Medical post operative complications [ Time Frame: participants will be followed for the duration of hospital stay, an expected median of 10 days ]participants will be followed for the duration of hospital stay, an expected median of 10 days
- Quality of life measured at 6 and 12 months postoperatively by the EQ-5D-5L questionnaire. [ Time Frame: 0,6 and 12 months ] [ Designated as safety issue: No ]
|Study Start Date:||September 2011|
|Estimated Study Completion Date:||September 2014|
|Estimated Primary Completion Date:||September 2014 (Final data collection date for primary outcome measure)|
Peripheral vascular disease
Subjects who have peripheral vascular disease
|Contact: Simon J Davies, MBChBemail@example.com|
|York Teaching Hospitals NHS Foundation Trust||Not yet recruiting|
|York, North Yorkshire, United Kingdom, YO318HE|
|Principal Investigator: Simon J Davies, MBChB|