Siegel M N, Gravenstein N
Department of Anesthesiology, University of Florida, College of Medicine, Gainesville 32610-0254.
J Clin Monit. 1990 Apr;6(2):89-92. doi: 10.1007/BF02828283.
The most efficient site for monitoring heart and lung sounds by esophageal stethoscope is not the warmest segment of the esophagus. This study investigated the ability of passive warming of airway gases to increase the accuracy of temperatures measured at this site (i.e., to decrease their difference from core temperature). In 15 adult patients undergoing general anesthesia and endotracheal intubation, esophageal temperatures were measured before and after use of a heat and moisture exchanger (an artificial nose) that passively warmed inspired gases. The resulting values were compared with nasopharyngeal temperatures, which represented core temperature. Before use of the heat and moisture exchanger, esophageal and nasopharyngeal temperatures differed significantly (mean difference +/- SD, 0.9 +/- 0.4 degrees C; P less than or equal to 0.001). After passive warming of inspired gases, esophageal temperatures increased significantly (mean increase +/- SD, 0.5 +/- 0.2 degrees C; P less than or equal to 0.001) but inconsistently (range, 0.1 to 1.2 degrees C). However, the mean difference between esophageal and nasopharyngeal temperatures was still significant (0.5 +/- 0.3 degrees C; P less than 0.001). Discrepancies between esophageal and core temperatures persist when a currently available esophageal stethoscope with adjacent auscultation chamber and temperature probe is used, despite passive warming of airway gases.
用食管听诊器监测心肺音的最有效部位并非食管中温度最高的节段。本研究调查了气道气体被动加温提高该部位所测温度准确性的能力（即缩小其与核心温度的差值）。在15例接受全身麻醉和气管插管的成年患者中，在使用被动加温吸入气体的热湿交换器（人工鼻）前后测量食管温度。将所得数值与代表核心温度的鼻咽温度进行比较。在使用热湿交换器之前，食管温度和鼻咽温度差异显著（平均差值±标准差，0.9±0.4℃；P≤0.001）。吸入气体被动加温后，食管温度显著升高（平均升高值±标准差，0.5±0.2℃；P≤0.001），但升高并不一致（范围为0.1至1.2℃）。然而，食管温度与鼻咽温度的平均差值仍然显著（0.5±0.3℃；P＜0.001）。尽管气道气体进行了被动加温，但使用目前配备相邻听诊腔和温度探头的食管听诊器时，食管温度与核心温度之间的差异依然存在。
