The determinants of propofol induction time in anesthesia / 대한마취과학회지

BACKGROUND: The required dose of anesthetics is generally smaller in patients with low cardiac output (CO). A high CO decreases the blood concentration of anesthetics during induction and maintenance of anesthesia. However, a high CO may also shorten the delivery time of anesthetics to the effect site, e.g. the brain. We assessed the time required for induction of anesthesia with propofol administered by target-controlled infusion (TCI), and investigated factors that modify the pharmacodynamics of propofol. METHODS: After measuring CO and blood volume (BV) by dye densitometry, propofol was infused using TCI to simulate a plasma concentration of 3 microg/ml. After infusion, the time taken to achieve bispectral index (BIS) values of 80 and 60 was determined. Age, sex, lean body mass (LBM), and cardiovascular parameters were analyzed as independent variables. The dependent variables were the time taken to achieve each BIS value and the plasma concentration of propofol (Cp) 10 min after the commencement of infusion. RESULTS: Multiple regression analysis revealed that a high CO significantly reduced the time taken to reach the first end point (P = 0.020, R2 = 0.076). Age and LBM significantly prolonged the time taken to reach the second end point (P = 0.001). Cp was negatively correlated with BV (P = 0.020, R2 = 0.073). CONCLUSIONS: Cardiac output was a statistically significant factor for predicting the time required for induction of anesthesia in the initial phase, whereas, age and LBM were significant variables in the late phase. The pharmacodynamics of propofol was intricately altered by CO, age, and LBM.

THE PRACTICE OF TAI CHI CHUAN IN MIDDLE AND ELDERLY PERSON AND ITS EFFECT TO STATIC AND DYNAMIC POSTURAL STABILITY / 体力科学

A balance test was given to middle-aged and elderly persons who are practicing Tai Chi Chuan for evaluating its effect on postural stability. The subjects were 34 (female : 34) healthy persons aged from 50 to 70 (mean : 63.2 ± 7.8years) .<BR>The Equitest System (Neuro Com Co. Ltd.) was used for the balance test. The Equitest System has several devices for evaluating postural balance both in a static and dynamic condition. The two tests used in this study-the Sensory Organization Test (SOT) and the Movement Coordination Test (MCT) -were performed to evaluate postural stability. The SOT consists of 3 static and 3 dynamic testing conditions, while the MCT evaluates postural response time against a shift board.<BR>The subjects were separated into 2 groups-beginner and skilled-for comparison between the two. The results of SOT showed that there were statistically significant differences of postural control in the dynamic condition between the two groups. But, there was no such difference seen in the static condition. For MCT, statistically significant differences were also observed between the two groups in the dynamic postural condition. The results of SOT and MCT suggest that skilled persons in Tai Chi Chuan acquire both highly developed dynamic balance and quick response in the disturbed condition.<BR>The results of the Cybex muscle strength test also suggests that the leg extensor develops muscle strength through long-term Tai Chi Chuan training.

Comparison of walking patterns of young and elderly men with a special reference to the characteristics of the lower leg movement / 体力科学

The purpose of this study was to clarify the characteristics of the gait function for the elderly with a special reference to the angle of the ankle joint and that of the metatarsophalangeal (MP) joint at heel contact and toe off. Five healthy young men (aged 22 to 23 yrs) and five healthy elderly men (aged 65 to 71 yrs) participated as the subjects in this study. The angle variation of the right ankle joint and that of the MP joint detected in goniometers were analyzed synchronously with the data of the force plate and the image data of bare foot movements during free, slow, and fast gait. The following results were obtained:<BR>1. The walking speed, step length, and cadence for the elderly during free gait were significantly small. Furthermore, the step length of the elderly was shorter than that of the younger subject even with the same height. Moreover, it was found that the fluctuation in both the step length and cadence resulted in an fluctuation in walking speed.<BR>2. One reason for the decrease in step length and cadence, and the increase in duration of the double supporting time for the elderly is the lowering of walking speed.<BR>3. The angle of the ankle at heel contact, the angle of the ankle at toe off, and the angular displacement of the MP joint were significantly smaller for the elderly during free gait and during walking within a range of speeds. Also, the angle of the ankle at heel contact, and the angle of the ankle at toe off for young and elderly subjects were separated into two groups during walking within a range of speeds. It may be showed that the reason for the smallness of the angle of the ankle at heel contact and the angle of the ankle at toe off for the elderly irrespective of walking speed is due to an elderly behavior that unconsciously makes the angle smaller to prevent the danger of falling.<BR>In conclusion, the difference in variables between young and elderly subjects during free gait and walking within a range of speeds exemplifies the characteristics of gait function for the elderly.

A Case of Common Hepatic Aneurysm with Anomalous Origin from the Aorta / 日本心臓血管外科学会雑誌

We describe a 52 year old woman who had an aneurysm involving the common hepatic artery directly originating from the aorta. It was successfully treated by aneurysmectomy without needing the arterial reconstruction. An aneurysm of the common hepatic artery that has an anomalous origin from the aorta is very rare and only 4 cases including the present case were reported in Japanese literature on our survey. The features and management of hepatic aneurysm are discussed.