Chiba Takashi, Yamauchi Misa, Nishida Naoki, Kaneko Taeko, Yoshizaki Katsuaki, Yoshioka Naofumi
Department of Social Medicine, Division of Forensic Sciences, Akita University School of Medicine, Hondo 1-1-1, Akita 010-8543, Japan.
Forensic Sci Int. 2005 May 10;149(2-3):151-8. doi: 10.1016/j.forsciint.2004.04.085.
A series of experiments were carried out to clarify the cause of death and the risk factors related to sudden death in the Japanese senior population while bathing in a Japanese style "hot bath." The biodynamic changes while bathing were carefully monitored under actual bathing situations occurring in both the winter and summer seasons. We observed double product (DP), total peripheral blood vessel resistance (TPR), cardiac output (CO), and blood vessel compliance (COMP) by measuring blood pressure, heart rate, pulse wave, and electrocardiogram (ECG). The finding of a high level of DP in the elderly suggests that more myocardial oxygen consumption is needed than for young adults, particularly in subjects with arrhythmia. Although the values for TPR and CO changed somewhat during bathing, the changes were considered normal and to be expected. However, more significant and substantial changes were observed during the winter experiment than during the summer experiment, no doubt owing to lower temperature of the bathing room. The value of COMP did not vary significantly between winter and summer subjects. Twelve subjects in the elderly developed ECG changes while bathing such as supraventricular extrasystole or ventricular tachycardia. No clinical significance was found in the biochemical analyses of the blood obtained before and after bathing. In conclusion, some subjects in the elderly showed risky changes in the above parameters and ECG, factors which may partially explain some of the causes of the many reported cases of lapse of consciousness and unexpected sudden death in the elderly while bathing especially in the winter season. Cold climate, hot water immersion, and hydrostatic pressure may affect their physiological compensation along with existing of coronary stenosis or weakness of respiratory function as a normal consequence of advanced age.
开展了一系列实验，以阐明日本老年人群在日式“热水浴”沐浴时的死亡原因及与猝死相关的风险因素。在冬季和夏季实际沐浴情况下，仔细监测沐浴时的生物动力学变化。我们通过测量血压、心率、脉搏波和心电图（ECG）来观察双乘积（DP）、总外周血管阻力（TPR）、心输出量（CO）和血管顺应性（COMP）。老年人中DP水平较高的发现表明，与年轻人相比，老年人需要更多的心肌耗氧量，尤其是有心律失常的受试者。尽管TPR和CO的值在沐浴期间有所变化，但这些变化被认为是正常的且在意料之中。然而，冬季实验期间观察到的变化比夏季实验期间更显著、更明显，这无疑是由于浴室温度较低。冬季和夏季受试者的COMP值没有显著差异。12名老年受试者在沐浴时出现了心电图变化，如室上性早搏或室性心动过速。对沐浴前后采集的血液进行生化分析未发现临床意义。总之，一些老年受试者在上述参数和心电图方面出现了有风险的变化，这些因素可能部分解释了许多报道的老年人在沐浴时尤其是在冬季出现意识丧失和意外猝死病例的一些原因。寒冷气候、热水浸泡和静水压力可能会影响他们的生理代偿，同时随着年龄增长，冠状动脉狭窄或呼吸功能减弱也是正常现象。
