ContentsContributorsAcknowledgments1. Clinical Engineering: Evolution of a Discipline Evolution of the Modern Health-Care System What is Clinical Engineering? Hospital Organization and the Role of Clinical Engineering Professional Status of Clinical Engineering Certification for Clinical Engineers Clinical Engineering Education Future of Clinical Engineering Exercises References2. Safety in the Clinical Environment Electrical Safety Safety Programs Summary Exercises References3. Technology Management Technology Management Program Medical Equipment Management Maintenance Schedules Computerized Maintenance Management and Information Systems Summary Exercises References4. Medical Technology: Assessment and Acquisition Technology Assessment Technology Assessment in Hospitals: An Example Acquisition of New Equipment Summary Exercises References5. Codes, Standards, and Regulations History Definitions Role of the United States Government Building Codes Voluntary Consensus Standards Organizations Voluntary Accreditation Organizations Trade Associations Professional Societies Listing Organizations International Standards Summary Exercises References6. Facilities Management and Design Facilities Management Facilities Design Case Study: Design of a Cardiac Catheterization Laboratory Summary Exercises References7. Management and Supervision Planning Preparing a Business Plan Organizing and Leading Controlling A Case Study: The Biomedical Instrumentation Department at the University of Texas, M.D. Anderson Cancer Center Summary Exercises References8. Development and Operation of a Clinical Engineering Department: A Practitioner's Perspective Development of a Clinical Engineering Program: Initial Steps Determination of Required Resources Program Management Summary Exercises References9. Computer Systems of Interest to Clinical Engineers Basic Computer Concepts The Binary Number System The Microcomputer Memory Storage and Input/Output (I/O) Devices Data Acquisition and Signal Processing Computer Networks Data Base Systems Computers in the Clinical Laboratory Patient Data Base Acquisition, Multiphasic Testing and Development of the Patient Medical Record Patient Monitoring Systems Medical Imaging Technology Diagnostic Support Systems: Expert Systems in Clinical Care Clinical Engineering and Management-Information Systems Summary Exercises References10. Moral and Ethical Issues in Clinical Engineering Practice The Ethical Significance of Professionalism Code of Ethics The Nature of Moral Judgments Defining Death: A Moral Dilemma Posed by Medical Technology Euthanasia Human Experimentation Regulation of Medical Device Innovation Conclusion: Equitable Access to Medical Technologies Exercises References11. Clinical Engineering: International Comparisons and Future Directions The First International Survey of Clinical Engineering Departments (1988) Major Conclusions of the First Study The Second Study (1991) Main Changes occurring Over the Three-Year Period (1988-1991) Conclusion ReferencesIndex
CHAPTER 1
CLINICAL ENGINEERING: EVOLUTION OF A DISCIPLINE
Publisher Summary
This chapter discusses the evolution of a clinical engineering as a new discipline. Biomedical engineering is an interdisciplinary branch of engineering with a foundation based in both engineering and the life sciences. It ranges from theoretical, nonexperimental undertakings to state-of-the-art applications. It can encompass research, development, implementation, and operation. Biomedical engineers apply electrical, chemical, mechanical, and other engineering principles to understand, modify, or control biological systems. When biomedical engineers work within a hospital or clinic, they are more properly called clinical engineers. However, this theoretical distinction is not always observed in practice as many professionals working in the U.S. hospitals today continue to be called biomedical engineers. In many hospitals, administrators have established clinical engineering departments to manage effectively all the technological resources, especially those relating to medical equipment, that are necessary for providing patient care. The primary objective of these departments is to provide a broad-based engineering program that addresses all aspects of medical instrumentation and systems support.
In the twentieth century, technological innovation has reshaped the field of medicine and the delivery of health-care services. Although the art of medicine has a long history, advances in medical technology, primarily in this century, have provided a wide range of positive diagnostic, therapeutic, and rehabilitative tools that are now routinely used in the cure of specific diseases and illnesses. In the process, the modern hospital in the United States has evolved as the center of a technologically sophisticated health-care system serviced by a technologically sophisticated staff.
With the dramatic role technology has played in shaping medical care, engineering professionals have become intimately involved in many medical ventures. As a result, the discipline of biomedical engineering has emerged as an integrating medium for two dynamic professions: medicine and engineering. Today, biomedical engineers assist in the struggle against illness and disease by providing materials, tools, and techniques (such as biomaterials, medical imaging, and artificial intelligence) that can be utilized for research, diagnosis, and treatment by health-care professionals. In addition, one subset of the biomedical engineering community, namely clinical engineers, has become an integral part of the health-care delivery team by managing the utilization of medical equipment within the hospital environment. The purpose of this chapter is to provide a broad overview of technology’s role in shaping our modern health-care system and to review the basic functions performed by clinical engineers within a hospital environment. This chapter also presents the status of the professionalization of clinical engineering (including certification), describes attributes of clinical engineering educational programs, and reflects upon the future of the discipline.
EVOLUTION OF THE MODERN HEALTH-CARE SYSTEM
Before 1900, medicine had little to offer the average citizen because its resources consisted mainly of the physician, his education, and his little black bag. In general, physicians seemed to be in short supply, but the shortage then had rather different causes than found today. Although the costs of obtaining medical training were relatively low, the demand for doctors’ services was also very small because many of the services provided by the physician could also be obtained from experienced amateurs in the community. The home was typically the site for diagnosis, treatment, and recuperation, and relatives and neighbors constituted an able and willing nursing staff. Babies were delivered by midwives, and those illnesses not cured by home remedies were left to run their natural, albeit frequently morbid, course. The contrast with contemporary health-care practices, in which specialized physicians and nurses located within the hospital provide critical diagnostic and treatment services, is dramatic.
The changes that have occurred within medical science originated in the rapid developments that took place in the applied sciences (chemistry, physics, engineering, microbiology, physiology, pharmacology, etc.) at the turn of the century. This process of development was characterized by intense interdisciplinary cross-fertilization, which provided an environment in which medical research was able to take giant strides in developing techniques for the diagnosis and treatment of disease. For example, in 1903, Willem Einthoven, the Dutch physiologist, devised the first electrocardiograph to measure the electrical activity of the heart. In applying discoveries in the physical sciences to the analysis of a biological process, he initiated a new age in both cardiovascular medicine and bioelectrical measurement techniques.
New discoveries in medical technology followed one another like intermediates in a chain reaction. However, the most significant innovation for clinical medicine was the development of X-rays. These “new kinds of rays,― as their discoverer W.K. Roentgen described them in 1895, opened the “inner man― to medical inspection. Initially, X-rays were used to diagnose bone fractures and dislocations. In the process, this “modern technology― became commonplace in most urban hospitals. Separate departments of radiology were established, and their influence spread to other departments throughout the hospital. By the 1930s, X-ray visualization of practically all organ systems had been made possible because of the inherent radiopacity of the body and the use of barium salts and a wide variety of radio-opaque materials.
X-ray technology gave physicians a powerful tool that, for the first time, permitted accurate diagnosis of a wide variety of diseases and injuries. Moreover, since X-ray machines were too cumbersome and expensive for local doctors’ clinics, they had to be placed in hospitals. Once there, X-ray technology essentially triggered the transformation of the hospital from a passive receptacle for the sick poor to an active curative institution for all members of society.
For economic reasons, the centralization of health-care services became essential because of many other important technological innovations appearing on the medical scene. However, hospitals remained institutions to dread, and it was not until the introduction of sulfanilamide in the mid-1930s and penicillin in the early 1940s that the main danger of hospitalization, i.e., cross-infection among patients, was significantly reduced. With these new drugs in their arsenals, surgeons were permitted to perform their operations with reduced morbidity and mortality due to infection. Furthermore, even though the different blood groups and their incompatibility were discovered in 1900 and sodium citrate was used in 1913 to prevent clotting, full development of blood banks was not practical until the 1930s when technology provided adequate refrigeration. Until that time, “fresh― donors were bled, and the blood was transfused while it was still warm.
Once these surgical units were established, employment of the available medical technology assisted in further advancing the development of complex surgical procedures. For example, the Drinker respirator was introduced in 1927, and the first heart-lung bypass was accomplished in 1939. By the late 1940s, medical procedures heavily dependent upon medical technology, such as cardiac catheterization and angiography (the use of a cannula threaded through an arm vein and into the heart with the injection of radio-opaque dye for the X-ray visualization of heart vessels and valves), were developed. As a result, accurate diagnoses of congenital and acquired heart disease became possible, and a new era of cardiac and vascular surgery was established.
Following World War II, the development of medical devices accelerated rapidly and the medical profession benefitted greatly from this rapid surge of technological finds throughout the next four decades.
Since it is impossible to cover all of the medical innovations that occurred during this period, consider just a few examples:
• Advances in electronics made it possible to map the subtle electrical behavior of the fundamental unit of the central nervous system–the neuron–and to monitor various physiological functions of patients in intensive care units (ICUs) by utilizing such diagnostic tools as the electrocardiogram (ECG) and the electroencephalogram (EEG). (Figure 1.1)
Figure 1.1 Modern bioelectric monitoring device used during surgery to monitor various physiological signals.
(Courtesy of Space Labs Medical, Inc. Redman, WA) • Nuclear medicine, an outgrowth of the atomic age, emerged as a powerful and effective approach to applying radioactive materials (tracers) to medical diagnosis and treatment. Activities in this area have included (a) the creation and use of radiopharmaceuticals; (b) the design and application of appropriate nuclear instrumentation to detect and display the activity of these radioactive elements; and (c) the determination of the relationship between the activity of radioactive tracers and specific...
