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David K Harrison

Publications and source records attributed to David K Harrison.

6 recordsLinked to original sources

Amputation level viability in critical limb ischaemia: setting new standards.

We have previously demonstrated the successful use of skin oxygen saturation (SO2) measurements to predict the healing viability in lower limb amputations for critical limb ischaemia. The measurements are quick and easy to perform, but the instrument that has been used to date is now obsolete and a new, lightweight, portable instrument has recently been introduced. However, fundamental differences between the two instruments could influence the criteria used for determining amputation level viability. The purpose of this study was to compare the in vivo measurements using the two instruments in order to validate amputation level viability criteria using the RM200. Skin SO2 measurements were carried out on critically ischaemic lower limbs of patients, and on the forearms of normal volunteers during before, during and after a 5 minute period of tourniquet ischaemia. A linear correlation (r2 = 0.91) was found between the values obtained from the two instruments within the range of interest (0 to 40% SO2). Differences between the instruments lay within 1 standard deviation of the mean, demonstrating a high degree of agreement between the two methods. The RM200 is thus an acceptable replacement for the MCPD instrument for amputation level viability assessments.

Amputation, Surgical↗

Optical measurements of tissue oxygen saturation in lower limb wound healing.

This review has highlighted the role of oxygen in wound healing and in the mechanism of preventing infection. Optical measurements of tissue SO2 in wounds can provide valuable information, not only about the inflammatory state of the wound, but also about healing potential in ulcers and critical limb ischaemia. The technique is fast, non-invasive and can be used without the necessity for contact with the skin.

Amputation, Surgical↗

Optical measurement of tissue oxygen saturation.

Advances in opto-electronic systems have meant that optical spectroscopy can now be used for noninvasive measurements in tissue in patients. A number of techniques have evolved over the last 15 years that make use of the characteristic differences in the absorption spectrum of deoxygenated and oxygenated hemoglobin to measure oxygen saturation. This article summarizes, in particular, those techniques that may prove to be applicable to measurements relating to lower extremity wounds. A short introduction is given about existing electrode methods before describing applications of near infrared and visible wavelength spectroscopy to measurements in tissue. The advantages and limitations of these methods are discussed. An example of an area where tissue spectroscopy is now in routine clinical use for tissue healing viability assessment is presented.

Journal Article↗