부산대학교 도서관

BACKGROUND:: Our purpose was to determine if there are reliable non-invasive methods to assess upper extremity ischemia regardless of skin pigmentation. METHODS:: We conducted a study of healthy subjects classified based on skin pigmentation using the Fitzpatrick Scale, the Von Luschan color scale, and self-described race (2 Hispanics, 3 Caucasians, and 4 African-Americans). A surface temperature probe and a near-infrared spectroscopy (NIRS) monitor were placed on the posterior interosseous artery skin territory. Temporary upper limb ischemia was induced by tourniquet insufflation. Readings from both devices were taken at baseline and every 15 seconds for a total of 10 minutes of ischemia. RESULTS:: During tourniquet insufflation we found a reliable decrease in tissue oxygenation measured by NIRS in all subjects and no significant change in temperature readings for any subjects. There was an average decrease of 19% in tissue oxygenation using NIRS, with measurements on average starting at 77% and ending at 57%. There was no significant difference in the change in NIRS oxygenation between participants with Fitzpatrick 3, 4, and 5 skin types or when participants were grouped into Fitzpatrick ≤3 versus >3, or when grouped into Fitzpatrick ≤4 versus >4. There was also no significant difference in participants grouped into Von Luschan scores ≤20 versus >20. CONCLUSION:: In this healthy subjects study, NIRS rapidly identified ischemia in all cases whereas skin surface temperature did not. NIRS may be a reliable way to non-invasively monitor for ischemia regardless of skin pigmentation degree.