Maltese Matthew R, Castner Thomas, Niles Dana, Nishisaki Akira, Balasubramanian Sriram, Nysaether Jon, Sutton Robert, Nadkarni Vinay, Arbogast Kristy B
The Children's Hospital of Philadelphia, 3535 Market Street, 11th Floor, Philadelphia, PA 19104, USA.
Stapp Car Crash J. 2008 Nov;52:83-105. doi: 10.4271/2008-22-0004.
Accurate pediatric thoracic force and deflection data are critical to develop biofidelic pediatric anthropomorphic test devices (ATDs) used in designing motor vehicle safety systems for child occupants. Typically, post-mortem human subject (PMHS) experiments are conducted to gather such data. However, there are few pediatric PMHS available for impact research, therefore novel methods are required to determine pediatric biomechanical data from children. In this study, we have leveraged the application of chest compressions provided in the clinical environment during pediatric cardiopulmonary resuscitation (CPR) to collect this fundamental data. The maximum deflection of the chest during CPR is in the range of chest deflections in PMHS impact experiments and therefore CPR exercises the chest in ways that are meaningful for biofidelity assessment. Thus, the goal of this study was to measure the force-deflection characteristics of the thorax of children and young adults during CPR. To do so, a force and deflection sensor was integrated into a patient monitor-defibrillator used during CPR in the Pediatric Intensive Care Unit and Emergency Department of a children's hospital. The sensor was interposed between the chest of the patient and hands of the rescuer during CPR compressions. Following a CPR event, thoracic force and deflection data were downloaded from the monitor-defibrillator for analysis. Each compression cycle was fit to a parallel spring-damper model, wherein stiffness and damping were linearly dependent on chest deflection. Average maximum chest deflection, force at maximum deflection, linear stiffness, and elastic and viscous model forces are reported for each subject and correlated with age. Eighteen subjects (11 females) ages 8 to 22 years were enrolled in the study and each received a mean of 2000 (Standard Deviation 2339) chest compressions during CPR. Average maximum chest deflection and corresponding force were 39 +/- 5 mm and 309 +/- 55 N respectively. When combined with our previous study of adult CPR data, and other data from the literature, our findings suggest that the stiffness of the thorax increases from youth to middle age, and then decreases in the elderly. CPR has the potential to provide data from a wide range of human subjects with which to study the effect of age on mechanics of thoracic deformation. Future studies will expand the sample size and age range of data collected to further explore the age-related changes in thoracic mechanics.
准确的儿科胸部受力和偏转数据对于开发用于设计儿童乘员机动车安全系统的生物逼真儿科人体模拟试验装置（ATD）至关重要。通常，会进行尸体人类受试者（PMHS）实验来收集此类数据。然而，可用于撞击研究的儿科PMHS很少，因此需要新的方法来从儿童中确定儿科生物力学数据。在本研究中，我们利用了儿科心肺复苏（CPR）临床环境中提供的胸部按压应用来收集这些基础数据。CPR期间胸部的最大偏转处于PMHS撞击实验中胸部偏转的范围内，因此CPR以对生物逼真度评估有意义的方式对胸部施加作用。因此，本研究的目的是测量CPR期间儿童和青年成人胸部的力-偏转特性。为此，将一个力和偏转传感器集成到儿童医院儿科重症监护病房和急诊科CPR期间使用的患者监护除颤器中。在CPR按压期间，传感器置于患者胸部和施救者手部之间。CPR事件后，从监护除颤器下载胸部受力和偏转数据进行分析。每个按压周期拟合到一个平行弹簧-阻尼器模型，其中刚度和阻尼与胸部偏转呈线性相关。报告了每个受试者的平均最大胸部偏转、最大偏转时的力、线性刚度以及弹性和粘性模型力，并与年龄相关。18名年龄在8至22岁的受试者（11名女性）参与了该研究，每个受试者在CPR期间平均接受了2000次（标准差2339）胸部按压。平均最大胸部偏转和相应的力分别为39±5毫米和309±55牛。当与我们之前对成人CPR数据的研究以及文献中的其他数据相结合时，我们的研究结果表明，胸部的刚度从青年到中年增加，然后在老年人中降低。CPR有可能提供来自广泛人类受试者的数据，用于研究年龄对胸部变形力学的影响。未来的研究将扩大收集数据的样本量和年龄范围，以进一步探索胸部力学中与年龄相关的变化。
