5 Enterprise Health Information Systems Healthcare institutions generate massive volumes of information that must be collected, transmitted, recorded, retrieved, and summarized. The problem of managing all these activities for clinical information has become monu- mental. As a result, computer-based hospital information systems (HISs) were designed, tested, and installed in hospitals of all sizes. The original purpose of HISs was to provide a computer-based framework to facilitate the communication of information within a hospital setting. Essentially, an HIS is a communication network linking terminals and output devices in key patient care or service areas to a central processing unit that coordinates all essential patient care activities. Thus, the HIS provides a communication sys- tem between departments (e.g., dietary,nursing units, pharmacy,laboratory); a central information system for receipt, sorting, transmission, storage, and retrieval of information; and a high-speed, data-processing system for fast, economic processing of data to provide information in its most useful form. The management of information in the hospital setting and its environs is a critical component in the process of healthcare delivery. The problem of information management has been complicated by an exponential increase in the amount of data to be managed, the number of stakeholders in the pro- cess, and the requirements for real-time access and response. In the United States, 12% to 15% of the cost of healthcare is attributed to the costs asso- ciated with information handling (Office of Technology Assessment, 1995). The cost of information handling in the hospital setting has led to the use of computers in an attempt to provide more data at lower costs. Estimates of the costs of information handling vary between 25% and 39% of the to- tal cost of healthcare (Jackson, 1969). Most health informatics professionals agree that a reasonable expenditure on information systems in healthcare is at least 3% to 5% of the operational budget for a health organization. This chapter is based in part on previously published material [Hannah, K.J., & Hammond, W.E. (1997). The evolution of clinical information systems. In: Ball, M.J., & Douglas, J. (eds.) Clinical Information Systems That Support Evolving Delivery Systems. Redmond: Spacelabs.] 57 58 Nursing Use of Information Systems Information systems currently being used in healthcare environments can be broadly categorized into three types. The first type is composed of systems that are limited in objective and scope. They most often exist as a stand-alone module and address a single application area. Examples of such a system are the nursing workload measurement systems currently being used in many hospitals. The Medicus and GRASP systems serve a specific function and therefore fall into this category of systems. In the hospital environment, sys- tems commonly included in this category are dedicated clinical laboratory systems, dedicated financial systems, and dedicated radiology, electrocar- diography, pulmonary function, pharmacy, and dietary systems. In a public health setting a stand-alone immunization system is a good example of this category of systems. The second type of information system is composed of hospital informa- tion systems, which usually consist of a communications network, a clinical component, and a financial/administrative component. The overall commu- nications component integrates these three major parts into a cohesive infor- mation system. A typical hospital information system in this category may have computer terminals at each nursing station as well as terminals that are in, or accessible to, each ancillary area in the hospital. The terminals are tied together through one or more large central computers, which may be on-site or off-site. Generally such systems are focused on acute care and are organized around departmental functions. The use of the third type of information system, enterprise health infor- mation systems (EHISs), is expanding in health environments. Such systems capture and store comprehensive patient information across the entire con- tinuum of care in health organizations using integrated healthcare delivery models. These records are captured and stored in multiple media including audio, image, animation, and print. The records may be stored centrally, in total or abstracted format, using a data warehouse approach. Alternatively, these records may be physically stored at the point of capture and logically linked to a virtual record that is physically assembled only when required to meet care requirements. These systems are characterized by the fact that they are focused on patients (rather than departments or disciplines) receiv- ing care in multiple integrated settings (e.g., ambulatory care, acute care, long-term care) having one common organizational structure (i.e., a single enterprise). An expanded type of EHIS has emerged recently as the elec- tronic health record (EHR) system. Several countries are moving toward developing nationwide electronic EHRs. Hospital Information Systems Early computer applications for hospitals dealt with administration and fi- nancial matters. Later applications included task-oriented functions such as admission/discharge/transfer (ADT), order entry, and result reporting. With Enterprise Health Information Systems 59 the availability of minicomputers and finally personal computers, various de- partmental service-related systems (e.g., laboratory, radiology, pharmacy) were developed. Few if any of these systems were electronically connected. The subsequent development of hospital information systems (HISs) was a combination of factors related to technology (hardware and software), people (developer and user), and economics. An implicit assumption in the development of HISs is that the ability of complete, accurate, timely data delivered at the point of care to the person providing that care results in a higher quality of care at a more efficient cost. Support for this assumption is provided by simple observation; for example, such systems should eliminate redundant tests, eliminate the need to reestablish diagnoses, increase awareness of drug allergies and adverse events, increase awareness of the medications the patient is taking, and en- hance communication among those involved with the patient’s care. There are four main functions typical of such hospital information systems. r Recognize both sending and receiving stations, format all messages, and manage all the message routing (called message switching) r Validate, check, and edit each message to ensure its quality r Control all the hardware and software needed to perform the first two functions r Assemble transaction data and communicate with the accounting system The first hospital computer systems developed during the late 1960s were geared to batch accounting to meet the complexity of third-party billing, cost statistics, and fiscal needs. The technology of that era was unsuccessfully ap- plied to clinical systems. Terminal devices, such as cathode-ray tubes, were expensive and unreliable. Also, hardware and software were limited, expen- sive, and highly structured. Database systems that we take for granted today had not appeared. During this period, some hospitals installed stand-alone computers in clinical departments and in business offices to do specific jobs. The most common clinical example is laboratory systems. Most of the hospi- tals that embarked on these clinical programs for stand-alone systems were large teaching institutions with access to federal funding or other research grants. Usually there was no attempt to integrate the accounting computer with the stand-alone departmental computers—this came much later. The 200 and 400 bed hospitals that installed computers during the late 1960s for accounting had varied success. During that period accounting needs became more complex, and this trend continues. The result is a constant battle just to maintain and change existing systems to keep pace with reg- ulating agencies. Many hospitals of this size turned to a shared computer service such as Shared Medical Systems. The reason these companies pros- pered was not only because of their products and services but also because a small hospital simply cannot justify employing and retaining the technical staff and management skills necessary for this complex, conflicting, changing environment. 60 Nursing Use of Information Systems During the early 1970s, with rampant inflation and restricted cost reim- bursement, some large hospitals that had installed their own computers with marginal success changed to the shared service. By this time, the shared com- panies had better accounting software and audit controls. Most importantly, these companies developed field personnel who understood hospital oper- ations and were able to communicate and translate the use of computer systems into results in their client hospitals. This added dimension of service that is not offered or understood by the hardware vendors increased business opportunities for the service companies. Many of these companies, in turn, increased their scope of services beyond fiscal to clinical and communication applications. The hardware vendors of the 1960s (e.g., IBM, Burroughs, Honeywell, NCR) committed themselves to large general-purpose computers that at- tempted to support clinical, communications, and financial systems. During the 1970s, technology such as the minicomputer and personal computer was generally