In our previous report, the electromagnetic immunity test on our arterial blood pressure measuring equipment demonstrated that the electromagnetic wave(3V/m, 34∼65MHz) increased the zero-point of our equipment to 50∼100mmHg. Besides, this malfunction was prevented by covering the reuse-cable of the equipment with the shield tube or the PC core. Therefore, EMI was considered to be the cause of the equipment malfunction in ICU. Then the electromagnetic waves were consecutively measured in ICU for 11 days in this study. It was demonstrated that the 60633 counts were detected as the total count for 11 days by the electromagnetic noise sensor. The electromagnetic waves with 5∼10V/m of which the strength could cause EMI were also detected among them. It was also demonstrated that those electromagnetic waves tended to be more often detected in the night than in the daytime.
Since the more electromagnetic waves were detected near the window side, they were considered to come from the outside of the hospital. Given our electromagnetic environment where our hospital is located near the center of the broadcast(Tokyo Tower) in Tokyo, the electromagnetic waves outside the hospital are highly considered to cause our arterial blood pressure measuring equipment to malfunction.

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Mayer wave(10s period or 0.1Hz fluctuation) included in heart rate variability and blood pressure variability appears apparently in the resting state. On the other hand, it can be predicted that a strong emotional reaction may affect the relationship between these variabilities. This prediction suggests that the human emotional reaction can be quantified by the maximum correlation coefficient ρ_max between heart rate and blood pressure whose frequency components are limited to the Mayer wave-band. However, the conventional method of obtaining ρ_max needs a bulky and expensive device for measuring continuous blood pressure. In this study, a smaller and cheaper device for measuring pulse wave transmission time(PTT) has been developed. This paper has shown that the PTT can give ρ_max instead of blood pressure and that ρ_max obtained by the PTT may significantly reflect the emotional reaction on the basis of an experiment using nine healthy subjects with nine self-produced devices in which pictures were presented to the subjects to induce their emotional reactions.

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To examine the possibility that the dexmedetomidine-induced cerebral vasoconstriction deteriorates ischemic brain damage, we administered dexmedetomidine during transient focal cerebral ischemia in rats. Rats received intravenous infusions of dexmedetomidine at 0.1μg·kg^-1·min^-1, and 1μg·kg^-1·min^-1 during cerebral ischemia induced by the occlusion of the middle cerebral artery with a nylon suture. Further, 5mg·kg^-1 of yohimbine combined with dexmedetomidine were also given during the cerebral ischemia. Cerebral infarction was detected in rats receiving infusions of dexmedetomidine at 0.1μg·kg^-1·min^-1 and 1μg·kg^-1·min^-11. Cerebral infarct volume was significantly larger in rats receiving dexmedetomidine infusion at 1μg·kg^-1·min^-1 than that of rats receiving at 0.1μg·kg^-1·min^-1. Treatment with yohimbine significantly decreased the dexmedetomidine-induced infarct volume by 84%. Therefore, it is suggested that the infusion of high-dose dexmedetomidine aggravates ischemic brain damage following focal cerebral ischemia in rats via the activation of alpha-2 adrenoceptor.

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We report our experiences in use of a minimal incision with retroperitoneal approach for treatment of patients with abdominal aortic aneurysm(AAA) and arteriosclerosis obliterans(ASO) in the aortoiliac area. Between January 2000 and March 2002, nineteen consecutive patients with the AAA or ASO underwent operation with a minimal incision technique(<10cm, group M), were compared with 25 patients treated in the same time period with conventional incision(>20cm, group C). There were no significant differences in operation time and cross-clamping time. There was no hospital death in both groups. With the advantages of minimal skin incision, less abdominal muscle dissection, optimal aortic exposure, early resumption of ambulation and shorter hospitalization time, we believe that this technique is a safe and less invasive method for use in abdominal aortic surgery.

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We encountered a patient with cerebral infarction developing simultaneously in both the left posterior cerebral artery and the left superior cerebellar artery. The patient had a history of myocardial infarction. Based on diagnostic images and the type of disease onset, the case seemed to be cerebral embolism. However, no source of embolism could be identified.

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Blunt trauma to a subclavian artery can result in intimal tears and secondary thrombosis of the arterial lumen. We report a case of subclavian artery occlusion due to this mechanism. Arterial flow to the upper extremity was restored by axillo-axillary bypass grafting. This less invasive procedure may also decrease the morbidity and mortality as compared with that using thoracotomy or sternotomy.

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