Assessment of Sympathetic Nerve Activity in Patients Under Enflurane Anesthesia by Computer Analysis of Laser-Doppler Skin Blood Flow Osamu Shimoda and Tatsuhiko Kano * Department of Anesthesiology, Kumamoto Rosai Hospi- tal, Yatsushiro 866, Japan, * Surgical Center, Kumamoto University Hospital, Kumamoto University Hospital, Ku- mamoto 860, Japan

We studied the quantitative expression of sympathetic nerve activity in the course of nitrous oxide (60%) and enflurane anesthesia. Skin blood flow was measured continuously from the 2nd finger-tip by means of laser Doppler flowmetry and later analyzed with a personal computer. The subjects were thirteen female patients undergoing laparoscopic examination. The quantitative parameters used were the percentage change in mean blood flow and the power density of the basic wave component (0.05-0.15 Hz) as a measure of blood flow fluctuation. At an enflurane concentration of 1.9%, the mean blood flow increased significantly to 256% the baseline value, while the peak amplitude and the band area of the basic wave component decreased signifi- cantly to 20% the baseline value. At the lower enflu- rane concentration of 1%, the mean blood flow did increase to 210%, while both parameters of the basic wave component increased to over 120% the baseline values. When tested 5 and 20 min after awakening from the anesthesia, each of the three parameters was significantly reduced to about 40% the baseline value. We conclude that the patterns of mean blood pressure and basic wave component are different in deep anes- thesia, in light anesthesia and during recovery from anesthesia. Analysis by laser Doppler flowmetry of skin blood flow could be useful for monitoring sympathetic nerve activity during clinical anesthesia.

(The Autonomic Nervous System, 30 (1993) 42-46)

Sympathetic Skin Response and Body Temperature in Patients with Cerebellar Degeneration Takanori Yokota *, Hiroshi Tsukagoshi * and Hitoshi Tanabe Department of Neurology, Tokyo Metropofitan Neurolog- ical Hospital, Tokyo 183, Japan, * Department of Neu- rology, Tokyo Medical and Dental University, Tokyo 113, Japan

Sympathetic skin response and body temperature were evaluated in 79 patients with cerebellar degeneration:

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41 with multiple system atrophy, 14 with familial olivo- pontocerebellar atrophy, 11 with familial cerebellar atrophy, and 9 with sporadic cerebellar atrophy. Body temperature was measured three times a day, for 2 weeks while the patients were free from infections, and maximum, minimum and average body temperatures were evaluated. The amplitude of the sympathetic skin response correlated with the maximum body tempera- ture but not with the minimum body temperature. The maximum body temperature in patients with abnormal sympathetic skin response was significantly higher that in patients with normal sympathetic skin response, whereas there was no difference in minimum body temperatures. The low level fever often observed in patients with cerebellar degeneration is considered to be due to hyperthermia caused by sweat disturbance; however, the temperature does not exceed 38.5°C.

(The Autonomic Nervous System, 30 (1993) 67-71)

Neurophysioiogically Optimal Drive Conditions for the Total Artificial Heart Tomoyuki Yambe, Shin-ichi Nitta, Yoshiaki Katahira, Taroh Sonobe, Shigeru Naganuma, Hiroshi Mat- suzawa, Hiroshi Akiho, Yoshito Kakinuma, Kenji Izutsu, Yuh-ichi Kikuchi, Motonao Tanaka, Makoto Miura *, Naoshi Sato *, Hitoshi Mohri *, Kyouichiroh Izumi **, Satoshi Koidc **, Hiroshi Takeda ** and Makoto Yoshizawa * * * Department of Medical Engineering and Cardiology, Re- search Institute for Chest Diseases and Cancer, Tohokt~ University, Sendai 980, Japan, * Department of Thoracic and Cardiovascular Surgery, Tohoku UnilTersity School of Medicine, Sendai 980, Japan, * * Department of Elec trical Engineering, Faculty of Engineering, Tohoku Uni- versity, Sendai 980, Japan, * ** Department of Knowl- edge-Based Information Engineering, Toyohashi Unit~er. si~ of Technology, Toyohashi 441, Japan

To determine the optimal drive conditions of total artificial heart, we analyzed the renal sympathetic nerve activity by means of power spectra and coherence functions. Two pneumatically actuated sac-type ven-- tricular assist devices were implanted as biventricular bypasses in acute experiments on sheep. After biven- tricular bypass pumping, the natural heart was electri- cally fibrillated to constitute a biventricular bypass-type total artificial heart model. After opening of thc left flank, a bipolar electrode was attached to the left renal sympathetic nerve via the retroperitoneal approach to detect the renal sympathetic nerve activity. Transfer