Principles and Considerations in the Early Identification and Prehospital Treatment of Thrombocytopenia.

Thrombocytopenia is a common condition characterized by a low platelet count, typically less than 150,000/µL. This article outlines key considerations for field medical providers to effectively identify the early signs of thrombocytopenia and treat different etiologies in the prehospital environment. Following a representative case study, we present a review of basic pathophysiology to include different manifestations of thrombocytopenia as well as diagnostic methods, treatments, and other necessary interventions in this unique setting. With an adequate understanding of typical patient histories and physical presentations leading to this diagnosis, field medics and physicians can be armed with useful information to potentially improve patient outcomes.

Two-Dimensional Modeling of Nanomechanical Strains in Healthy and Diseased Single-Cells During Microfluidic Stress Applications.

Investigations in cellular and molecular engineering have explored the impact of nanotechnology and the potential for monitoring and control of human diseases. In a recent analysis, the dynamic fluid-induced stresses were characterized during microfluidic applications of an instrument with nanometer and picoNewton resolution as developed for single-cell biomechanics (Kohles, S. S., Nève, N., Zimmerman, J. D., and Tretheway, D. C., 2009, "Stress Analysis of Microfluidic Environments Designed for Isolated Biological Cell Investigations," ASME J. Biomech. Eng., 131(12), p. 121006). The results described the limited stress levels available in laminar, creeping-flow environments, as well as the qualitative cellular strain response to such stress applications. In this study, we present a two-dimensional computational model exploring the physical application of normal and shear stress profiles (with 0.1, 1.0, and 10.0 Pa peak amplitudes) potentially available within uniform and extensional flow states. The corresponding cellular strains and strain patterns were determined within cells modeled with healthy and diseased mechanical properties (5.0-0.1 kPa moduli, respectively). Strain energy density results integrated over the volume of the planar section indicated a strong mechanical sensitivity involving cells with disease-like properties. In addition, ex vivo microfluidic environments creating in vivo stress states would require freestream flow velocities of 2-7 mm/s. Knowledge of the nanomechanical stresses-strains necessary to illicit a biologic response in the cytoskeleton and cellular membrane will ultimately lead to refined mechanotransduction relationships.