Transcutaneous Oximetry, Transcutaneous Carbon Dioxide and Supplemental Oxygen Therapy in Lower Limb Amputations

Study Overview
=================
Brief Summary
-----------------
TCOM is a multicentre prospective cohort study in patients undergoing lower limb amputations. Patients will provide oxygen and carbon dioxide measurements in the lower limb for 20 to 30 minutes before their surgery and will be followed up until 6 months after their surgery. The purpose of the TCOM study is to determine the ability of oxygen and carbon dioxide measurements in the legs of patients undergoing lower limb amputation to predict wound healing complications and to determine an optimum cutoff value for both oxygen and carbon dioxide levels beyond which healing complications are likely to occur and a closer amputation level is indicated.

Detailed Description
-----------------
Lower limb amputation is a serious and unfortunate outcome for many patients with vascular disease, especially those with diabetes. It results in significant decreases in all aspects of quality of life. The need for further surgery to revise the amputation to a more proximal level leads to increased potential for serious and life-threatening complications, as well as a decrease in patient morale. From surveys and background literature, it can be estimated that there are approximately 8600 vascular disease-related lower limb amputations in Canada each year. As the epidemic of diabetes continues to unfold and the mean age of the population increases, this number is expected to increase. The results of this study may significantly assist in the surgical and clinical care of this patient population by providing clinicians with a means to assess appropriate lower limb amputation levels. Further, the modalities of transcutaneous measures may assist in guiding further intervention studies in higher risk patients to improve clinically important outcomes. This study will act in part as a feasibility trial for a randomized controlled trial assessing the efficacy of supplemental oxygen therapy, including hyperbaric oxygen therapy, as a therapeutic tool to increase rates of healing after lower limb amputation.

Official Title
-----------------
Transcutaneous Oximetry, Transcutaneous Carbon Dioxide and Supplemental Oxygen Therapy in Lower Limb Amputations - An Observational Study

Conditions
-----------------
Amputation Wound

Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Age ≥ 18 years Requires a lower limb amputation between the ankle and knee due to vascular complications Provides written informed consent Exclusion Criteria: Requires a lower limb amputation for non-vascular reasons, including trauma and cancer Requires primary amputation below the level of the ankle or above the knee

Ages Eligible for Study
-----------------
Minimum Age: 18 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| leg amputation<br>Patients undergoing below-knee and above ankle amputation for vascular reasons will receive transcutaneous oximetry and transcutaneous carbon dioxide measurement | |

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Composite of all-cause 30-day mortality and healing failure of the surgical stump | Composite of all-cause 30-day mortality and healing failure of the surgical stump at 30 days postoperatively, defined as the need for amputation revision. | 30 days post-surgery | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| 6-month all-cause mortality. | 6-month all-cause mortality | 6 months post-surgery | 
| Incidence of re-amputation from 30 days to 6 months post-amputation | Incidence of re-amputation from 30 days to 6 months post-amputation | 6 months post-surgery | 
| Use of prosthesis for mobilization within 6 months post-amputation | Use of prosthesis for mobilization within 6 months post-amputation | 6 months post-surgery | 
| Change in health-related quality of life from baseline at 6-months post-amputation | Change in health-related quality of life from baseline at 6-months post-amputation, based on the quality of life questionnaire (EuroQoL-5D) | 6 months post-surgery | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
leg amputation, transcutaneous oximetry, transcutaneous carbon dioxide, wound healing failure, amputation revision