Related Experiment Videos
Limb perfusion in the lower limb amputee--a comparative study using a laser Doppler flowmeter and a transcutaneous
S L Fairs1, R O Ham, B A Conway
1Department of Medical Engineering and Physics, King's College School of Medicine and Dentistry, London.
Prosthetics and Orthotics International
|August 1, 1987
Summary
Laser Doppler flowmetry (LDF) with thermal stressing offers a non-invasive method to objectively assess lower limb amputation levels. This technique shows significant differences in blood flow responses between control and amputee groups, correlating well with transcutaneous oxygen measurements.
Area of Science:
- Vascular Surgery
- Medical Devices
- Diagnostic Techniques
Background:
- Accurate assessment of lower limb amputation level is crucial for patient management.
- Non-invasive techniques are sought to objectively determine amputation sites.
- Laser Doppler flowmetry (LDF) measures skin blood flow and has potential pre-operative applications.
Purpose of the Study:
- To evaluate the efficacy of Laser Doppler flowmetry (LDF) combined with thermal stress for objectively determining lower limb amputation levels.
- To compare LDF measurements with transcutaneous oxygen measurements (TcPO2) in patients undergoing amputation for vascular disease.
Main Methods:
- Pre-operative LDF measurements were performed on 25 vascular amputee patients and 5 controls.
- Baseline and post-heating skin blood flux were recorded on the medial aspect of the legs.
- Transcutaneous oxygen measurements (TcPO2) were taken at the same sites for comparison.
Main Results:
- Significant differences in TcPO2 were observed between controls, below-knee (BK), and above-knee (AK) amputees (p < 0.001).
- Heated LDF flux showed significant differences between controls and both BK and AK groups (p < 0.005), and between amputee groups.
- The relative increase in LDF flux (heated/baseline) significantly differed between controls, BK, and AK groups (p < 0.001) and correlated with TcPO2 (r=0.7, p < 0.001).
Conclusions:
- Laser Doppler flowmetry (LDF) with thermal stressing provides a quick, simple, and non-invasive method for objective amputation level determination.
- This technique shows promise in differentiating between healthy tissue, below-knee, and above-knee amputation levels.
- LDF offers a valuable adjunct to existing methods like TcPO2 for pre-operative assessment in vascular amputees.