Bender Janelle E, Shang Allan B, Moretti Eugene W, Yu Bing, Richards Lisa M, Ramanujam Nirmala
Department of Biomedical Engineering, Duke University, 136 Hudson Hall, Box 90281, Durham, NC 27708, USA.
Opt Express. 2009 Dec 21;17(26):23396-409. doi: 10.1364/OE.17.023396.
We conducted a pilot study on 10 patients undergoing general surgery to test the feasibility of diffuse reflectance spectroscopy in the visible wavelength range as a noninvasive monitoring tool for blood loss during surgery. Ratios of raw diffuse reflectance at wavelength pairs were tested as a first-pass for estimating hemoglobin concentration. Ratios can be calculated easily and rapidly with limited post-processing, and so this can be considered a near real-time monitoring device. We found the best hemoglobin correlations were when ratios at isosbestic points of oxy- and deoxyhemoglobin were used, specifically 529/500 nm. Baseline subtraction improved correlations, specifically at 520/509 nm. These results demonstrate proof-of-concept for the ability of this noninvasive device to monitor hemoglobin concentration changes due to surgical blood loss. The 529/500 nm ratio also appears to account for variations in probe pressure, as determined from measurements on two volunteers.
我们对10名接受普通外科手术的患者进行了一项初步研究，以测试可见波长范围内的漫反射光谱作为手术中失血的非侵入性监测工具的可行性。测试波长对处的原始漫反射率比值作为估计血红蛋白浓度的初步方法。比值可以通过有限的后处理轻松快速地计算出来，因此这可以被视为一种近实时监测设备。我们发现，当使用氧合血红蛋白和脱氧血红蛋白等吸收点处的比值时，与血红蛋白的相关性最佳，特别是529/500纳米。基线扣除改善了相关性，特别是在520/509纳米处。这些结果证明了这种非侵入性设备监测因手术失血导致的血红蛋白浓度变化能力的概念验证。根据对两名志愿者的测量，529/500纳米的比值似乎也能解释探头压力的变化。
