Popov Todor A, Dunev Stefan, Kralimarkova Tanya Z, Kraeva Steliana, DuBuske Lawrence M
Clinic of Allergy and Asthma, Medical University Sofia, 1, Sv. Georgi Sofiyski Street, BG 1431, Sofia, Bulgaria.
Respir Med. 2007 Oct;101(10):2044-50. doi: 10.1016/j.rmed.2007.06.005. Epub 2007 Jul 12.
Inflammation is a universal pathological reaction and is characterized among other things by increased heat production. The question stays whether the contribution of the inflamed lung tissues to the overall exhaled breath temperature (EBT) can be reliably detected and used in everyday clinical practice.
We have designed a simple device for assessment of EBT and explored its performance under standard indoor conditions. We made our measurements in the morning hours, documenting the ambient conditions (room temperature, humidity, atmospheric pressure), and physiological characteristics of the tested subjects (heart rate, blood pressure, otic and axillary temperature). We assessed its day-to-day reproducibility in 17 healthy volunteers and its ability to discriminate between the same subjects without respiratory disease and uncontrolled asthmatics (n=14). We also compared the EBT of the 14 asthmatics before and after anti-inflammatory treatment.
No association was found between EBT and any of the ambient conditions: room temperature, atmospheric pressure and humidity. While otic and axillary temperatures, which were measured in parallel, maintained high correlation between each other (Spearman's rho=0.71, p<0.01), EBT did not show meaningful association with any of them. The EBT (degrees C) of asthmatics (median 35.45, range 34.12-36.09) was higher than that of controls (34.84, 32.29-35.84), (p=0.009, Mann-Whitney U test). Anti-inflammatory treatment brought down the EBT of the asthmatics (34.78, 33.23-36.06), (p=0.001, Wilcoxon Signed Ranks test), while significantly improving their spirometry too.
Measurements of EBT with the device we constructed are not significantly influenced by changes within the accepted range of a standard indoor environment. EBT represents a different characteristic of the human organism than otic and axillary temperatures. EBT is increased in uncontrolled asthmatics and decreases under anti-inflammatory treatment.
炎症是一种普遍的病理反应，其特征之一是产热增加。问题在于发炎的肺组织对总体呼气温度（EBT）的贡献能否在日常临床实践中被可靠检测并加以利用。
我们设计了一种用于评估EBT的简单装置，并在标准室内条件下探究其性能。我们在上午时段进行测量，记录环境条件（室温、湿度、大气压）以及受试对象的生理特征（心率、血压、耳温和腋温）。我们评估了该装置在17名健康志愿者中的每日可重复性，以及区分无呼吸系统疾病的同一受试对象和未控制的哮喘患者（n = 14）的能力。我们还比较了14名哮喘患者在抗炎治疗前后的EBT。
未发现EBT与任何环境条件（室温、大气压和湿度）之间存在关联。虽然同时测量的耳温和腋温彼此之间保持高度相关性（斯皮尔曼等级相关系数rho = 0.71，p < 0.01），但EBT与它们中的任何一个均未显示出有意义的关联。哮喘患者的EBT（摄氏度）中位数为35.45，范围为34.12 - 36.09，高于对照组（34.84，32.29 - 35.84），（p = 0.009，曼 - 惠特尼U检验）。抗炎治疗使哮喘患者的EBT降低（34.78，33.23 - 36.06），（p = 0.001，威尔科克森符号秩检验），同时也显著改善了他们的肺功能测定结果。
使用我们构建的装置测量EBT不受标准室内环境公认范围内变化的显著影响。EBT代表了人体不同于耳温和腋温的一种特征。EBT在未控制的哮喘患者中升高，在抗炎治疗下降低。
