Kei Sato

Power Spectral Analysis of Beat-to-beat Variability during Inhalation Anesthesia in Dogs.

犬6頭を用いてハロセン, イソフルラン吸入麻酔下における心拍変動を最大エントロピースペクトル分析をした結果, 低・高周波数帯 (0.02～0.09Hzと0.15Hz以上) のピークの周波数, 振幅値および面積値は, 麻酔濃度の上昇にともなって変化し, 変動様式ではイソフルランとハロセンの両者間に差が認められた。よって麻酔下における心拍変動の周期解析は, 自律神経系のモニターとして有用な方法であることが示唆された。

Changes in Cell-mediated Immunological Function after Operation in Dogs.

外科的侵襲に対する犬の細胞性免疫機能を評価するために実験的に麻酔や手術負荷を加えた後にルミノール依存性化学発光 (CL: chemilumines cence) 測定法により免疫担当細胞である好中球, マクロファージ, 末梢血リンパ球 (PBL) の動態について検討した。その結果は麻酔群ではCL活性の変動はほとんど見られなかった。手術群では, 術後1日目から全血 (好中球) および一細胞当たりの活性増強と好中球の増多が観察された。その後3日目にかけて全血 (好中球) 活性が低下すると同時に, マクロファージ, PBLの活性増強が認められた。以上のことから本実験で用いたCL測定法は術前術後の免疫機能診断法の一つとして有用性が高いものと思われる。

Serum Concentrations of Ampicillin-Na Infused during General Anesthesia in Dogs.

Ampicillin Na (AB-PC) was administered intravenously at a rate of 10 mg/kg/hr for 2 hours to the dogs anesthetized with halothane and enflurane, respectively. The AB-PC concentration reached the maximal values 2hours after the anesthesia (halothane 18.82 μg/ml, enflurane 19.57 μg/ml) which were approximately 1.4 times higher than that of the control dogs (13.84 μg/ml) . In addition, that the lower excretion rate was shown in the anesthetized dogs when terminating the drip infusion of AB-PC may indicate the depression of the excretion during anesthesia. The phenomena mentioned above are considered as the results caused by the deterioration of the blood-tissue permeation. Further study is necessary on the infusion method for maintaining AB-PC concentration during and after the operation.

Effects of Electrical Stimulation on Living Tissue

When platinum electrodes of four different lengths were buried in the rabbits ear and a micro-current was applied, the shorter the electrodes were the greater the rise in potential and the faster the process was. The potentials then remained high throughout the experiment. The positive potential was always greater, but the ratio of positive to negative decreased as the length of the electrodes was shortened.

Effects of peritoneal dialysis on the recovery from pentobarbital anesthesia in dogs.

The effect of peritoneal dialysis on the recovery from anesthesia was evaluated using 10 healthy mixed-breed dogs. The animals were given sodium pentobarbital (25 mg/kg) intravenously. After a surgical anesthesia was attained, peritoneal dialysis was performed using a metal catheter and a commercial dialysis fluid. The arousal time, respiratory rate, heart rate, body temperature, blood pressure and ECG were recorded during and after the dialysis. Furthermore, the pentobarbital concentration in the collected fluid was measured.In 6 of the 10 dogs receiving peritoneal dialysis, the arousal time was decreased to 70 % of those in control dogs. Two other dogs showed no significant reduction, and the rest of the dogs showed a longer arousal time. In addition, the mean pentobarbital concentration in the collected dialysate fluid (273 ml/head) was as low as 6.4μg/ml. Between the control and the dialysis group, no significant difference was found in clinical findings and physiological data.