The Effect of Inclusion of Rhythmic Music on the Effectiveness of Basic Life Support (BLS) Education

PURPOSE: An adequate chest compression rate during CPR is associated with improved hemodynamics and primary survival rate. The purpose of this study was to compare performance based measures of chest compression (CC), including compression rate and depth, from two versions of a CPR course: Instructor-led (IL) training, and the same IL training but augmented with rhythmic music. METHODS: Ninety-one medical students having completed the BLS provider course, 4 months prior, participated in CPR quality improvement education. Participants performed 2 min of CC on a manikin utilizing an accelerometer-based system that measured both rate (CC/min) and depth (cm) of CC. CC parameters were evaluated three times: prior to the education, immediately after the education, and again after four months. CPR quality was analyzed using the manikin/accelerometer system. The primary outcome measures included: (1) compression rate, (2) compression depth, (3) percentage of compressions performed with adequate rate, (4) percentage of compressions performed with adequate depth, (5) absolute deviation from 100 in terms of compression rate, and (6) each 2 minute test was divided into 4 30 second sections, and any rate differences between the 4 sections were assessed. For the augmented IL study, popular music with a tempo of 100 beats per minute was utilized. RESULTS: There were no differences in CC rate and depth between the two IL trainings. However, students offered IL training augmented with musical rhythm performed CC with a higher percentage of adequate rate and depth. They also had less absolute deviation and variation of CC rate difference between the four, 30 second sections, than students instructed without the use of rhythmic music. CONCLUSION: Students receiving IL training augmented with music performed adequate, standardized CC with a steadier rate than those who received IL training without the benefit of music. This result provides evidence to support the use of rhythmic music in improving BLS education results.

Stress Distribution According to Center-Edge Angle in Dysplastic Hip and the Biomechanical Effect of Rotational Acetabular Osteotomy / 대한정형외과학회잡지

PURPOSE: The purpose of this study was to estimate the biomechanical effect of rotational acetabular osteotomy by analyzing the stress on the surface of the femoral head according to center-edge (CE) angle by computer simulation. MATERIALS AND METHODS: We performed computer simulation by simplifying the pelvis and femur to 3-dimensional flat stress. We analyzed the change of distribution of stress and the amount of deformation according to the degree of acetabular dysplasia, represented by the change of CE angle, by using a Finite element model (FEM). Stress and deformation were calculated in two cases that underwent rotational acetabular osteotomy. RESULTS: In the FEM model, the stress was 3.74 MPa at a CE angle of 30.and the deformation was 1.37 mm. The stress was 14 MPa at 15., 34.2 MPa at 0., and 82.4 MPa at -15. In a case of rotational acetabular osteotomy, the pre-operative and post-operative stresses were 26.1 MPa and 5.16 MPa, and the maximal deformations were 16.1 mm and 1.6 mm, respectively. CONCLUSION: As the severity of acetabular dysplasia increases, the stress concentration also increases. When the CE angle is below 0., a high concentration of stress develops. After rotational acetabular osteotomy, maximal stress was reduced to normal levels and sufficient stress distribution was achieved.