Noninvasive diagnosis of carbon monoxide poisoning using Extended Modified Lambert Beer Model

We aim to demonstrate the feasibility of using Extended Modified Lambert Beer model (EMLB) to detect differences in percent mean blood oxyhemoglobin (S_mO₂) and carboxyhemoglobin (S_mCO) saturations between smoking and nonsmoking populations. The value of these parameters is given by those that produced the closest agreement between the EMLB and the measured data optimized using the developed fitting routine. This fitting algorithm used extinction coefficients of light absorbing hemoglobin species in the wavelength range of 520-600 nm as the background information. The reflectance spectroscopy measurement on left thumb of five smokers and four nonsmokers at rest condition revealed percent S_mO₂ and S_mCO with mean value of 81.9 ± 8.8% and 16.2 ± 4.8%, respectively, for smoking population. Meanwhile a higher mean S_mO₂ of 86.5 ± 1.6% and lower mean S_mCO of 11.7 ± 1.6% are observed for nonsmoking individuals. These values are compared to that reported in the literature. This study concluded that the proposed model and fitting strategy is able to detect differences in percent blood saturations of smoking and nonsmoking volunteers, hence potentially be used to clinically detect carbon monoxide poisoning in men.