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The best example of a clinical information system with an integrated clinical decision support system is the HELP (Health Evaluation though Logical Processing), pioneered by Dr. Homer Warner and his colleagues at the Latter Day Saints Hospitals (LDS) in Salt Lake City, Utah, USA and successfully implemented since 1982 in a 550-bed general hospital manned almost exclusively by a staff of 290 specializing in private practice (Pryor, T.A., 1983 and 1984).

The HELP System

The HELP system was pioneered by Dr. Homer Warner and his colleagues at the LDS Hospital in Salt Lake City, Utah, USA. It is designed to provide consultation based on current medical knowledge, to the specialist caring for a patient who has problems outside his special area of expertise, and to the generalist, who is faced with a problem that he may not recognize or a situation which he lacks the experience to tackle. Since the system reacts automatically to each new data entry by examining new data in the context of all pertinent previous data on this patient according to rules specified and the medical logic stored in the form of decision criteria, the appropriate medical knowledge will always be promptly brought to bear on each patient’s problem. When new knowledge is acquired, an additional modification can easily be made to the appropriate component of the system and that new knowledge will automatically be applied in solving the patient’s problem from that moment onwards.

Design for the HELP System Most of the information about a patient is acquired automatically or through paramedical persons. The Help system is designed to be data-driven. Each time a new item of information is added to a patient’s file, any decisions that make use of that information are automatically processed at that time. Since decision logic is not static over time but changes as new medical knowledge is acquired, logic in the HELP system is stored independently of the computer program that executes it. As new medical knowledge becomes available, the decision criteria can modified without changing any program in the computer. A common program processes all medial logic and only this common program need to be implemented on another computer in order to transfer the medical-ware directly. HELP decisions are expressed in a natural language so that a medical expert with no computer experience can generate the logic with enough confidence to assume responsibility for the decisions that the computer makes. The decision logic, therefore, is self-explanatory, and hence transportable from one institution to another. Since the system is data-driven, the logic for at least one decision is processed almost as soon as the item of information is entered into a patient’s file. In order to accomplish efficient and economic processing of this logic, the natural language source statements representing medical logic are converted into a tightly coded form ready for efficient processing before they are stored on a disc for use by the system. Much effort has gone into this kind of optimization. The HELP system is designed to allow the user to not only use sophisticated logical and probabilistic expressions, but also to specify complex relations in time sequences among the data required to make a decision. In addition, the system is hierarchical in order that some decision may be based on other decisions as well as raw data to any level desired. HELP is designed to be modular so that it can start performing a useful service even with a small subset of its essential complement of decision logic. This modularity also facilitates division of responsibility for the system logic among experts, with each one managing the decisions in his area of expertise. Without this, the maintenance of such a complex system, would become overwhelming. The HELP system has been designed to provide most of the information needed to improve upon its current decision logic. The system itself can provide data that will form a basis for improved logic in the future. SOURCES OF DATA FOR DECISION –MAKING

Each patient on elective admission to the hospital takes a self-administered history questionnaire while setting at a terminal (details of history taking by computer are given in the next chapter). From the answer to these questions, HELP decisions are processed on the basis of conditional probabilities to provide the attending physician with a list of suggested diagnoses and the reasons for these suggestions. This procedure and the other components of the screening process are designed to detect secondary problems that may alter patient management because most patients whose physicians use Help are coming into hospital for elective surgery. An electrocardiogram (ECG) is obtained on each patient during the screening and processed online by the computer. The variables that have been extracted by the ECG program and stored in the patient record are interpreted by the ECG program and stored in the patient record are interpreted by the HELP system. A comparison of serial ECGs is also made by the HELP system (details of ECG analysis by computer are given in Chapter 7). Spirometry is also performed online as part of the screening operation. A report of these first three items of information is printed in the screening facility and the ward with the patient. In the pulmonary function laboratory, several more sophisticated breathing functions as well as blood gas values are measured using instruments connected online to the computer. Processed data as well as interpretations based on HELP logic are fed back to the technician as part of the quality control process. In the exercise laboratory, three channels of electrocardiographic information are processed on request from the technician or monitoring cardiologist at various stages of exercise. Signal averaging after rejection of extra systoles is employed o provide a clean signal for interpretation. In the cardiovascular laboratory, all hemodynamic data are acquired online during the procedure. Left ventricular angiograms are recorded on video discs and then processed by computer to detect areas of wall motion abnormality. The Clinical laboratory, including chemistry, hematology and various special procedures is online to a stand-alone laboratory computer system, which, in turn, interfaces with the HELP system; when these data are verified by a responsible technician, they are transmitted to the HELP system for storage in the patient file. This triggers off the processing of any logic that uses particular data items. Three files are maintained in the blood bank on each unit of blood-a donor file, a unit file and a record in the file of the patient who receives the unit of blood. Every prescription of the pharmacy is entered by the pharmacist through a terminal. The computer prints labels, maintains a drug file for each patient and turns to HELP to decide whether a particular prescription is potentially hazardous to the patient in the light of his known sensitivities, other drugs he is taking, his kidney function or other variables that might be deduced from the laboratory or other data in his file. If an alarm is generated the clinical pharmacist goes to the ward to bring this information to the attention of the responsible physician or nurse. Demographic information obtained during the admitting process may be used for certain decisions. In the record room, additional information including the discharge diagnosis is abstracted from the patient’s written chart. The 31 ICU and CCU beds are monitored directly by the computer for a variety of hemodynamic and rhythm measurements and recordings. Observations by the nurses are entered through the terminal in order to provide a computer record that contains all the information needed for patient care. Finally, there are terminals on all 31 nursing stations which are used for entering certain types of information such as increased patient temperature. However, these are primarily used for reviewing patient data. MODES OF DECISION OUTPUT TO PHYSICIAN

The decision made by the HELP system and the data used for these decisions are available to the physician in three modes. These are discussed in detail below:

Routine reports on video terminal –there are four types of routine reports upon which HELP decisions may appear. These include: The report from all the laboratories; Admission screening report; The eight –hour shift report; and The cumulative five-day report in the ICU and CCU. The physician may gain access to HELP decisions on his patients through a keyboard – video terminal in the doctor’s lounge, at each nursing station or in any of the intensive care units. He does this by calling a program that asks him for his code number and then display a list of patients who are his responsibility. The list of current decisions on any patient may then be examined, as well as the latest data from the sources just described.

Hard copies of the data displayed in the terminals can be obtained from the doctor’s lounge or the ICU of any of this information. The third mode of decision output is in the form of alerts to the clinical pharmacist in case of potential adverse drug reactions to a prescription; to a nurse or clinician for problems such as increase in the patient’s temperature or laboratory values which indicate severe electrolyte disturbances that are not being managed appropriately. In the ICU, certain decisions may turn on a red light on the monitoring panel. When a nurse or resident presses that light switch, a message describing the alert is displayed on the terminal. Finally, such programs are operational that provide the chief of any service with the facility to follow the course of all patients in any category that he described, by the logical combination of HELP decisions in the system. For instance, the chief of pathology can follow up reports on a day-to-day basis on all patients who have a hypochromic microcytic anemia but who have not undergone a serum iron and TIBC test.

Systems like HELP provide quality review while corrective measures are still possible for the patient. The system also prompts what appropriate action should be taken. A positive feedback situation is created with improved accuracy of data, improved analysis of data and improved logic of decision –making. The block diagram of the Tandem Computer system used for HELP is given in Fig. 12.1, and the list of applications on the HELP system is given in Table 12.1.

ADT (Admission, Discharge, Transfer)

Order Entry/Charge Capture

Pharmacy

Clinical Lab

Radiology

Blood Gas

Pulmonary Functions

Heart Catheterization

Cardiology/EKG

Hemodynamic /ECG Monitoring

Medical Records

Peer Review

Research