Physiologic changes on the rescuer and efficiency of CPR in the increased chest compression

흉부압박의 횟수증가가 구조자에게 미치는 생리학적 변화와 심폐소생술 정확도에 미치는 영향

Purpose : This study was designed to examine physiological changes in the body of rescuers conduct CPR according to the 2005 new guideline from American Heart Association. The ratio of artificial respiration has changed from 15 : 2 into 30 : 2 in 2005. The researcher tried to know the correlation between the physiological changes and the accuracy of CPR. Method : The examinees of this study were 26 students (Dept. of Emergency Medical Service). After the training, participants conducted 10 minute CPR and soon after the CPR, their vital signs were checked, and lactic acid and concentration of ammonia were analysed from their blood samples. Questionnaires to ask their subjective fatigue level were filled out after blood samples and 10 minute - CPR was performed. Results : 1) After the CPR, concentrations of ammonia were $149.71{\mu}{\ell}/d{\ell}$ and $162.17{\mu}{\ell}/d{\ell}$ in 15 : 2 and 30 : 2, respectively. The number was higher in 30 : 2 but it wan not statistically meaningful (p = .493). Log value of lactic acid was a little higher in 30 : 2 with 42 log($mmol/{\ell}$) and 54 log($mmol/{\ell}$) in 15 : 2 and 30 : 2, respectively but it was not statistically meaningful (p = .113). 2) Blood pressure in 15 : 2 and 30 : 2 were 118.50 mmHg and 125.08 mmHg while pulse in two different cases were 96.14 and 97.25, showing no statistically significant differences (blood pressure : p = .155, pulse : p = .841). 3) Subjective fatigue was a bit high in 30 : 2 with 5.93 and 6.92 points in 15 : 2 and 30 : 2 respectively but it was not statistically meaningful (p = .142). 4) In the 10 minute CPR, respiration accuracy was 96.21% in 15 : 2 and 94.79% in 30 : 2. There was no statistical significances between the two(p = .225). In the meanwhile, chest compression accuracy was 92.57% in 15 : 2 and 91.83% in 30 : 2. From the beginning to the end of chest compression, there showed no difference(p = .425). the type of CPR did not influence upon the accuracy of chest compression(p = .756). Conclusion : In the CPR conducted by skilled rescuers for 10 minutes, there were no statistically meaningful differences between 15 : 2 and 30 : 2 in the concentration of fatigue element in a blood, subjective fatigue, vital signs and accuracy of CPR. Therefore, 30 : 2 CPR recommended by American Heart Association need to be recommended and performed in scene size up.