Abstract
The purpose of this study was to find the most effective frequency of the practice session in the closed chest cardiac massage. Fifteen healthy nurse-school female students were randomly divided into three different experimental groups (n=5). The first group (M-g) practiced once a week for one month. The second group (W-g) exercised one practice session per day for four days, and the third group (D-g) four practice sessions in one day. Each practice session consisted of one minute of intensive training under the supervision of the present investigators. The thorax compression force was measured using a force measurement device attached to a cardiac massage dummy (the Leardal's Recording Resuci Anne), and the angle of elbow was also measured by means of an electro-goniometer system. The measurement was done before and after each practice session, and one month and 6 months after the final practice session. During each practice session each subject was instructed that an ideal magnitude of the force was 40 kg, and the elbows were straightened (0 degree) throughout the compression phases.
It was found that the compression forces before the first practice session were 34.94±1.22 kg, 35. 3±2.24 kg, and 34.9±3.39 kg for M-g, W-g, and D-g, respectively. There were no significant differences in these mean values of three groups. The compression force after the four practice sessions for each group was significantly larger than its corresponding initial mean value. The M-g had 42.1±0.97 kg, and the W-g and D-g had 39.5±1.05 kg and 39.5±0.20 kg, respectively. It was noted that these values were similar to the ideal force of 40 kg, suggesting that each training method was equally effective.However, there were significant differences in the compression forces when measured 6 months after the final practice session. The W-g and D-g had an apparent decremental effect in the compression force, and the greatest change was seen in D-g. There were no significant changes in the elbow angle due to the effects of time. These results suggested that lessons of the cardiac massage should be spaced over a relatively longer period of time.
