皮膚組織加熱前後血流與血量的相關性

The relationship between blood flow and blood volume of in skin tissue before and after heating

林建源(Chien-Yuan Lin)

指導教授 ： 蔡正倫

中原大學/工學院/醫學工程研究所/碩士(2001年)

https://doi.org/10.6840/cycu200100216

摘要

植皮手術是治療中重度燒燙傷的主要方法，而各部位燒燙傷程度判斷的準確性，直接影響手術的成功率，然而，燒傷程度的判斷卻仍是一大難題。一般外科醫師，多半由其外觀與感覺功能，做主觀判斷，因而容易造成許多誤判，延誤治療時機。由於燒傷程度最難判別的地方就是2度深層及3度燒傷的模糊地帶，而其所達之深度約為綠光的穿透深度，由於深度不深所以光源與檢測器的距離需盡量靠近，因而採用細光纖來做光的傳導與檢測，且光源採用綠光半導體雷射(532nm)。目前臨床上使用雷射都卜勒測量加熱前後血流速的改變，在判斷燒傷深度已有不錯的結果，為了研究是否能以更簡單的血量量測來取代血流量測，因此本研究架構一光纖式血流及血量量測系統，藉由量測皮膚組織在加熱前後都卜勒頻譜的變化作為血流變化的指標以及同時量測光血管收縮舒張造成的血量改變使光吸收度產生變化亦即觀察光體積描繪圖（PPG）做為血量的變化的指標。依照這些指標來瞭解皮膚組織中微血管是否仍能正常擴張，以判斷皮膚燒燙傷程度。實驗結果顯示血流血量的頻譜在加熱之後確有明顯的變化，各部位都卜勒的平均頻移量在加熱之後變大範圍在120% ~ 350%之間，以臉部的變化最明顯。血量在加熱後的變大範圍在180% ~ 550%之間。
因此組織加熱的血量改變，較血流的改變更靈敏，由於血量量測較簡單，未來將有可能發展出比雷射血流計更便宜的燒傷深度量測儀器。

關鍵字

光體積描繪圖 ； 綠光半導體雷射 ； 光纖式血流血量量測系統 ； 燒燙傷程度 ； 都卜勒頻譜

並列摘要

Skin-grafting is a main method to treat deep burns. The success of skin grafting greatly depends on the correct determination of burn depth. However, this is still very difficult in clinical practice. Most burn depth diagnosis is still by the clinical assessment of an experienced burn surgeon. Although the judgment could be quite accurate for very deep or very shallow burns, clinical assessment of the second degree and the third degree of burns are very difficult. One promising method for measuring the burn depth is to evaluation the change in blood flow after heating. The blood flow of microcirculation in skin tissue is measured using laser Doppler flowmeter. Since skin burn is only a few hundred microns in depth and this is about the penetration depth of green light in skin tissue, green light diode laser (532 nm) was used as the light source. The probing depth is also restricted by the size of optical fibers and the distance between them
In this study, a measurement system was built to simultaneously measure the changes in skin blood flow and blood volume before and after heating to 42°C. The experiment results show that the Doppler mean frequency at different measuring sites increased from 120% to 350% and the signal of photoplethysmography (the change in blood volume) could increase from 180% ~ 550%. In general, the change in tissue blood volume is more obvious than the change in blood flow after heating. Therefore, a photoplethysmography can be used to replace the more expensive and complex laser Doppler flowmeter.

並列關鍵字

The degree of burns ； Doppler frequency ； green light diode laser ； optic-fibre measurement system for blood flow an

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