Edward Charles DeLand

FLUID BALANCE AND ELECTROLYTE DISTRIBUTION IN THE HUMAN BODY

This Memorandum presents a conceptual model and a mathematical method for computing the physiological fluid and electrolyte distribution for selected body compartments of an average, young, 70-kilogram human male. The mathematical procedure simulates the physiological subsystems by incorporating all the known chemical reactions and electrochemical relations which seem necessary to establish the fluid and electrolyte distribution. Because the whole body is being considered, the relatively large number of computations required argues that a computer be employed, The construction of the model and the mathematical background is given in heuristic form only, with reference to earlier papers for rigorous development. However, considerable detail is shown regarding the analysis of the computed results for a standard, steady-state, average, young, resting, 70-kg human male. Finally, the results of validation experiments, consisting of chemical stresses applied to the model, are discussed. In some cases, these results are compared with similar experiments in the biological literature, but in others reference is made to a companion paper by G. B. Bradham, et al. (1), in which particular laboratory validation experiments are described in detail. The results of these experiments indicate that the model is a valid supplementary tool for research in the clinical and the research laboratory as well as in theoretical physiology.

A mathematical model of the human external respiratory system.

This study examines the thesis that a part of the human physiological system can be simulated by a suitably constructed mathematical model. The model employed derives from a class of mathematical programming methods that were originally developed for representing complex military and industrial activities and have recently been used to represent involved chemical equilibria. The motivation for this research is the long-range view that a successful mathematical simulation of the human system or of human subsystems would provide an important tool for biological investigations. A sufficiently complex mathematical model-that is, a model that embodies sufficiently complex mathematical model-that is, a model that embodies sufficient chemical and biological detail to represent a whole, functioning human system or subsystem-could be used to explore biological hypotheses, environmental stress reactions, and interplay of dependent subsystems, and could serve as a pedagogical tool or even as an aid to medical diagnosis. Of course, the foregoing long-range view is an ultimate goal. For the moment, only the techniques, concepts, and characteristics of such a mathematical model are being explored. This paper presents the results of a simulation of the external respiratory function. Respiration, and the consequent gas exchanges at the lung surfaces, involves many chemical reactions and a transformation of venous blood into arterial blood. This activity was chosen as a test cast to explore the feasibility of constructing a mathematical model of a human subsystem.

BIOMOD: an interactive computer graphics system for modeling

Many of those involved in improving the quality of life often model and simulate continuous systems as part of their work. For example, one group of investigators may model an oil refinery to learn how to produce a new fuel efficiently, while another may simulate a global weather model to determine the effect of burning large quantities of the fuel at high altitudes. An urban planning team may simulate the water flow in an estuary to discover the best location for a new sewage treatment plant or the effect of a proposed breakwater. A medical team may simulate the bodily distribution of drugs to determine optimal dosage amounts and intervals, while another team might simulate the blood-volume control system to design a more efficient artificial kidney.

Technological opportunities for the delivery of health care

This paper has been designed to examine the programs and aspirations assigned to the National Center for Health Services Research and Development which has just recently been created in Washington, D. C. This Center will be supported by grants and contracts, and will endeavor to promote, support, and stimulate a national program of health-services research, development, and demonstrations. More specifically, the National Center for Health Services Research and Development will attempt to make health services available to all people and to assist all health professions in their efforts to improve their ability to assess the quality of their services. It will also investigate the comparative costs of alternative methods of providing and financing health services and experiment with architectural designs, site locations, plans, and new methods of construction. The Center will try to increase the efficiency of health services by developing new methods of training and using personnel. Applying and refining computer technology in screening techniques, automation of medical records, and selected other aspects of medical care process will be included in the program, as well as methods for accelerating the applications of new or improved techniques for the prevention, treatment, and control of diseases and other disabilities. The Center will design and initially operate experimental health-services systems in both urban and rural areas. It will make multi-disciplinary analyses of the organization and functioning of all components of the health-services system and will increase academic resources for training health-services research and for developing personnel. The Center will establish and operate a health-services data system relevant to research and development, planning, policy making, and management. Much of this paper discusses the opportunities which exist in the development of computer technology in the United States in relation to the delivery of health care.