Tissue Vascular Optics and Impedance Measurements for the Detection of Early Tissue Damage and Pressure Ulceration

Study Overview
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Brief Summary
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Pressure ulcers are common, distressing and expensive. Currently scoring systems and checks by nursing staff are carried out to assess a patient's risk of developing a pressure ulcer. The investigators would like to see whether non-invasive measurements can be taken from patients to predict who might be at risk of pressure ulcers to allow us to intervene and reduce the risk of it happening.

Detailed Description
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Pressure ulcers are common, distressing and expensive. Currently scoring systems and checks by nursing staff are carried out to assess a patient's risk of developing a pressure ulcer. The aim is to investigate whether non-invasive physiological measurements can be taken from patients to predict who might be at risk of pressure ulcers to allow us to intervene and reduce the risk.

Official Title
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Optical Pressure Ulcer Study: Tissue Vascular Optics and Impedance Measurements for the Detection of Early Tissue Damage and Pressure Ulceration

Conditions
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Pressure Ulcer

Intervention / Treatment
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* Other: Physiological measurements from heel


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: HEALTHY VOLUNTEERS: Able to give consent Male or female Over the age of 18 years No known peripheral vascular disease No known tissue damage Able to read and understand basic English language PATIENTS: Able to give consent Male or female Over the age of 18 years Either at risk (Braden scale <17) or confirmed Category 1 or 2 PU or confirmed DTI Well enough to attend lab without any attachments (IV fluids, IV medications, oxygen) Able to transfer to bed with assistance of one Able to read and understand basic English Language Exclusion Criteria: HEALTHY VOLUNTEERS: Presence of tissue damage or ulceration in the foot Known peripheral vascular disease Known hypersensitivity to fixation tape Presence of a pacemaker Participants unable to or refusing to give informed consent PATIENTS: Known hypersensitivity to fixation tape Participants unable to or refusing to give informed consent Unable to transfer to bed with assistance of one. Requiring more than routine observations and requiring attachments (IV fluids, IV medications, oxygen) Presence of a pacemaker

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 99 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Healthy volunteer<br>Physiological measurements from heel over 60 minute period | Other: Physiological measurements from heel<br>* Measurements of blood flow, tissue oxygen saturation, temperature, pressure<br>|
| At risk of Pressure Ulcer<br>Physiological measurements from heel over 60 minute period | Other: Physiological measurements from heel<br>* Measurements of blood flow, tissue oxygen saturation, temperature, pressure<br>|
| Confirmed Catefory I Pressure Ulcer<br>Physiological measurements from heel over 60 minute period | Other: Physiological measurements from heel<br>* Measurements of blood flow, tissue oxygen saturation, temperature, pressure<br>|
| Suspected Deep Tissue Injury<br>Physiological measurements from heel over 60 minute period | Other: Physiological measurements from heel<br>* Measurements of blood flow, tissue oxygen saturation, temperature, pressure<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Laser Doppler Flowmetry | Laser light to assess perfusion of heel | 20 minutes | 
| Spectrometry | Light spectrometry to assess tissue oxygen saturation of the heel | 20 minutes | 
| Impedance | Measurement of oedema of the heel | 5 minutes | 
| Temperature | Thermal image of heel to assess skin temperature | 5 minutes | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Co-morbidities | The presence of peripheral arterial disease, ischaemic heart disease, diabetes and previous pressure ulcers | 5 minutes |