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R S Evans

Publications and source records attributed to R S Evans.

At least 19 recordsLinked to original sources

Decision support in medicine: examples from the HELP system.

Computerized health information systems can contribute to the care received by patients in a number of ways. Not the least of these is through interactions with health care providers to modify diagnostic and therapeutic decisions. Since its beginning, developers have used the HELP hospital information system to explore computerized interventions into the medical decision making process. By their nature these interventions imply a computer-directed interaction with the physicians, nurses, and therapists involved in delivering care. In this paper we describe four different approaches to this intervention. These include: (1) processes that respond to the appearance of certain types of clinical data by issuing an alert informing caregivers of these data's presence and import, (2) programs that critique new orders and propose changes in those orders when appropriate, (3) programs that suggest new orders and procedures in response to patient data suggesting their need, and (4) applications that function by summarizing patient care data and that attempt to retrospectively assess the average or typical quality of medical decisions and therapeutic interventions made by health care providers. These approaches are illustrated with experience from the HELP system.

Adult

The timing of prophylactic administration of antibiotics and the risk of surgical-wound infection.

BACKGROUND: Randomized, controlled trials have shown that prophylactic antibiotics are effective in preventing surgical-wound infections. However, it is uncertain how the timing of antibiotic administration affects the risk of surgical-wound infection in actual clinical practice. METHODS: We prospectively monitored the timing of antibiotic prophylaxis and studied the occurrence of surgical-wound infections in 2847 patients undergoing elective clean or "clean-contaminated" surgical procedures at a large community hospital. The administration of antibiotics 2 to 24 hours before the surgical incision was defined as early; that during the 2 hours before the incision, as preoperative; that during the 3 hours after the incision, as perioperative; and that more than 3 but less than 24 hours after the incision, as postoperative. RESULTS: Of the 1708 patients who received the prophylactic antibiotics preoperatively, 10 (0.6 percent) subsequently had surgical-wound infections. Of the 282 patients who received the antibiotics perioperatively, 4 (1.4 percent) had such infections (P = 0.12; relative risk as compared with the preoperatively treated group, 2.4; 95 percent confidence interval, 0.9 to 7.9). Of 488 patients who received the antibiotics postoperatively, 16 (3.3 percent) had wound infections (P less than 0.0001; relative risk, 5.8; 95 percent confidence interval, 2.6 to 12.3). Finally, of 369 patients who had antibiotics administered early, 14 (3.8 percent) had wound infections (P less than 0.0001; relative risk, 6.7; 95 percent confidence interval, 2.9 to 14.7). Stepwise logistic-regression analysis confirmed that the administration of antibiotics in the preoperative period was associated with the lowest risk of surgical-wound infection. CONCLUSIONS: We conclude that in surgical practice there is considerable variation in the timing of prophylactic administration of antibiotics and that administration in the two hours before surgery reduces the risk of wound infection.

Adult

Computerized identification of patients at high risk for hospital-acquired infection.

Surveillance for hospital-acquired infections is required in U.S. hospitals, and statistical methods have been used to predict the risk of infection. We used the HELP (Health Evaluation through Logical Processing) Hospital Information System at LDS Hospital to develop computerized methods to identify and verify hospital-acquired infections. The criteria for hospital-acquired infection are standardized and based on the guidelines of the Study of the Efficacy of Nosocomial Infection Control and the Centers for Disease Control. The computer algorithms are automatically activated when key items of information, such as microbiology results, are reported. Computer surveillance identified more hospital-acquired infections than did traditional methods and has replaced manual surveillance in our 520-bed hospital. Data on verified hospital-acquired infections are electronically transferred to a microcomputer to facilitate outbreak investigation and the generation of reports on infection rates. Recently, we used the HELP system to employ statistical methods to automatically identify high-risk patients. Patient data from more than 6000 patients were used to develop a high-risk equation. Stepwise logistic regression identified 10 risk factors for nosocomial infection. The HELP system now uses this logistic-regression equation to monitor and determine the risk status for all hospitalized patients each day. The computer notifies infection control practitioners each morning of patients who are newly classified as being at high risk. Of 605 hospital-acquired infections during a 6-month period, 472 (78%) occurred in high-risk patients, and 380 (63%) were predicted before the onset of infection. Computerized regression equations to identify patients at risk of having hospital-acquired infections can help focus prevention efforts.

Cross Infection

Prevention of adverse drug events through computerized surveillance.

Adverse drug events (ADEs) are a serious health problem and are the leading adverse event experienced by hospitalized patients. Numerous hospitals have used different methods to improve the reporting of ADEs but few have undertaken studies aimed at the prevention of ADEs. We found that computerized ADE surveillance identified significantly more ADEs than our previous voluntary reporting method. Moreover, the computerized ADE surveillance system created a database of ADEs which allowed us to analyze the ADEs and design methods for prevention. We found that computer alerts of previously known drug allergies generated when drugs were ordered significantly reduced the number of type B ADEs, 56 vs 8 (p < 0.001). In addition, we found that the timely surveillance of ADEs combined with physician notification reduced the number of severe ADEs, 41 vs 12 (p < 0.001). Initial analysis of the ADE database has shown that on average patients with type B ADEs are hospitalized longer (17 vs 14 days) and have larger hospitalization costs ($30,617 vs $23,256) than patients with type A ADEs. Patients with severe ADEs also are hospitalized longer (20 vs 13 days) and have larger hospitalization costs ($38,007 vs $22,474) than patients with moderate ADEs. This indicates that the prevention and early treatment of ADEs can reduce the length of hospitalization and result in a considerable cost savings to the hospital.

Clinical Pharmacy Information Systems

Intensive surveillance of midazolam use in hospitalized patients and the occurrence of cardiorespiratory arrest.

Midazolam, a benzodiazepine used extensively as a sedative and a hypnotic for patients undergoing inpatient and outpatient medical procedures, has been associated with several side effects, the most serious of which are cardiac and respiratory arrest. We studied the use of midazolam and its association with cardiac and respiratory arrest among hospital patients at our institution. From 1988 through 1990 we identified 5439 patients exposed to midazolam, representing 8% of all patients admitted; 3031 (55.7%) received midazolam while not on mechanical ventilation. In the majority of patients the drug was given as a one-time dose, and the total dose was less than or equal to 5 mg in more than 70%. Three patients (0.099%) experienced respiratory arrest. All three events occurred within 2 hours after the last dose of midazolam had been given. All patients were elderly and all survived. The rate of respiratory arrest appears low at our institution and was associated with high doses of midazolam, concurrent use of opiates, and use in elderly patients.

Aged

Computerized surveillance of adverse drug events in hospital patients.

OBJECTIVE: To develop a new method to improve the detection and characterization of adverse drug events (ADEs) in hospital patients. DESIGN: Prospective study of all patients admitted to our hospital over an 18-month period. SETTING: LDS Hospital, Salt Lake City, Utah, a 520-bed tertiary care center affiliated with the University of Utah School of Medicine, Salt Lake City. PATIENTS: We developed a computerized ADE monitor, and computer programs were written using an integrated hospital information system to allow for multiple source detection of potential ADEs occurring in hospital patients. Signals of potential ADEs, both voluntary and automated, included sudden medication stop orders, antidote ordering, and certain abnormal laboratory values. Each day, a list of all potential ADEs from these sources was generated, and a pharmacist reviewed the medical records of all patients with possible ADEs for accuracy and causality. Verified ADEs were characterized as mild, moderate, or severe and as type A (dose-dependent or predictable) or type B (idiosyncratic or allergic) reactions, and causality was further measured using a standardized scoring method. OUTCOME MEASURE: The number and characterization of ADEs detected. RESULTS: Over 18 months, we monitored 36,653 hospitalized patients. There were 731 verified ADEs identified in 648 patients, 701 ADEs were characterized as moderate or severe, and 664 were classified as type A reactions. During this same period, only nine ADEs were identified using traditional detection methods. Physicians, pharmacists, and nurses voluntarily reported 92 of the 731 ADEs detected using this automated system. The other 631 ADEs were detected from automated signals, the most common of which were diphenhydramine hydrochloride and naloxone hydrochloride use, high serum drug levels, leukopenia, and the use of phytonadione and antidiarrheals. The most common symptoms and signs were pruritus, nausea and/or vomiting, rash, and confusion-lethargy. The most common drug classes involved were analgesics, anti-infectives, and cardiovascular agents. CONCLUSION: We believe that screening for ADEs with a computerized hospital information system offers a potential method for improving the detection and characterization of these events in hospital patients.

Adolescent

The HELP system and its application to infection control.

The HELP system is a comprehensive hospital information system that is linked to an allied financial data base. The clinical data base integrates information from areas such as admitting, pharmacy, radiology, surgery, pathology, nursing, respiratory therapy, and the clinical laboratories, including microbiology. This allows for the creation of an electronic medical record that contains all the clinical and financial data for each patient. The HELP system combines both communication and advice features through the use of data- and time-driven algorithms. We have used the HELP system to automate the surveillance and analysis of hospital-acquired infections and to identify patients at high risk for nosocomial infection. The expert system features have also been used to suggest alternatives for patients receiving inappropriate antimicrobial therapy, to improve the timing of antibiotic prophylaxis in surgery, and to curtail unnecessarily prolonged prophylaxis. Automated hospital information systems such as HELP can facilitate the investigation of a broad range of infection control, quality improvement, and cost-containment issues.

Cross Infection

Surveillance for quality assessment: IV. Surveillance using a hospital information system.

Hospital surveillance for infection control purposes is a well-accepted method of following nosocomial infections in U.S. hospitals. However, hospital surveillance is being increasingly performed for nosocomial events in noninfectious areas, such as quality assurance and other areas of outcomes research. For the continued development of hospital surveillance in all these areas, dramatic growth in the amount of information collected will occur. To accommodate this growth and to validate new approaches in these areas, large amounts of data collection will be necessary. Collection of these data will be quite difficult without the creation of clinical hospital data bases in which large amounts of information are collected as a routine part of patient care, not as an elaborate addition to patient care. Automated hospital information systems, such as the HELP system, can facilitate the conduct of ongoing hospital surveillance not only in infection control but also in a broad range of areas, such as quality improvement outcomes research and cost-containment areas.

Cross Infection

Development of a computerized adverse drug event monitor.

Adverse events during drug therapy are receiving renewed attention. Some adverse drug events (ADEs) are identified only after the widespread clinical use of a drug. The Food and Drug Administration advocates post-marketing surveillance systems to provide early warnings of previously undetected ADEs. The identification of ADEs by U.S. hospitals is now required by the Joint Commission on Accreditation of Healthcare Organizations. We developed a series of computer programs and data files on the HELP System to help identify ADEs. The HELP System monitors laboratory test results, drug orders, and data entered through a computerized ADE reporting program. A nurse or pharmacist verifies computer alerts of possible ADEs. The computerized system identified 401 ADEs during the first year of use compared to 9 by voluntary reporting methods during the previous year (p less than 0.001). This paper describes the development and early use of the computerized ADE surveillance system.

Adverse Drug Reaction Reporting Systems

Therapeutic antibiotic monitoring: surveillance using a computerized expert system.

STUDY OBJECTIVE: To develop and evaluate a computerized system to monitor therapeutic antibiotics in a hospital setting. MATERIAL AND METHODS: From November 1986 through October 1987, we prospectively monitored 1,632 hospitalized patients who had 2,157 microbiology specimens sent for culture and sensitivity testing. During the study period, computer algorithms were used to identify patients whose antibiotic therapy was inappropriate in relation to microbiology culture and sensitivity data. When inconsistencies occurred between antibiotic therapy and in vitro sensitivity data, computer algorithms generated therapeutic antibiotic monitor (TAM) alerts. A clinical pharmacist then notified the attending physician of the alert. RESULTS: Antibiotic therapy was identified by the computer as inappropriate in 696 instances (32%). After we eliminated false-positive alerts, 420 evaluable TAM alerts remained. Physicians responded to the TAM alerts by either changing or starting antimicrobial therapy in 125 cases (30%). Moreover, physicians were previously unaware of the relevant susceptibility test results in 49% of the alerts. CONCLUSION: Computer-assisted monitoring is an efficient and promising method to identify and correct errors in antimicrobial prescribing and to assure the appropriate use of therapeutic antibiotics.

Algorithms

Computer-critiqued blood ordering using the HELP system.

Recently the medical risk of blood transfusions has emphasized the need to improve the safe use of blood products. For the past 2 1/2 years at LDS Hospital we have used the HELP computer system to assist and critique ordering of blood products "on-line" by physicians and nurses. This report details the computer methods used to order blood products and to critique the appropriateness of those orders. Physicians personally enter the orders for more than 45% of the blood products using computer terminals, whereas 7% are from physician standing orders. Nurses enter the remaining orders from written orders (26%), verbal orders (14%), and phone orders (8%). There were 3396 blood orders for 1043 patients generated by 273 physicians during the fourth quarter of 1989. Each order is justified at the time it is entered by selecting from a menu of physician-approved criteria. The criteria are linked to supportive data in the data base, i.e., laboratory results and clinical data. The computer verified that 82% of these orders met criteria. Quality Assurance nurses verified the remaining 18%. Of these 18% only one in eight required manual chart review. After computer and Quality Assurance review, only eight (0.24%) of the orders were found to be true exceptions to established criteria. Physicians and nurses have accepted the computerized critiquing system. Through use of the computer we provide "on-line" critiquing and improve the use of scarce blood product resources.

Blood Banks

Reducing the duration of prophylactic antibiotic use through computer monitoring of surgical patients.

The use of antibiotic prophylaxis for unnecessarily prolonged periods after surgical procedures can contribute to increased health care costs and adverse drug reactions as well as the development of antibiotic-resistant infections. Hospitals are under economic pressures to develop methods to control the excessive use of these drugs. We expanded the capabilities of our hospital information system to monitor the duration of surgical antibiotic prophylaxis. For six months during one year we used the computer system to monitor antibiotics received by every surgical patient and to identify patients receiving antibiotic prophylaxis longer than was deemed necessary according to generally accepted guidelines. For six months in the following year we used the system to monitor and identify the same types of patients and clinical pharmacists placed antibiotic "stop orders" in the charts of the patients identified by the computer. Surgical patients received an average of 19 doses of antibiotics in the first year compared with 13 doses in the second year (p less than 0.001). The average cost of antibiotics received more than 48 hours after the operation was $42 less per patient in year 2 than in year 1, resulting in a potential cost savings of $44,562 in six months. The computer system was found to be an efficient tool for monitoring all antibiotics given to surgical patients and identifying patients receiving antibiotic prophylaxis longer than necessary. Clinical use of this system appears to have resulted in improved usage of antibiotic prophylaxis.

Anti-Bacterial Agents

Improved perioperative antibiotic use and reduced surgical wound infections through use of computer decision analysis.

A prospective study was performed over a two-year period to determine whether computer-generated reminders of perioperative antibiotic use could improve prescribing habits and reduce postoperative wound infections. During the first year, baseline patterns of antibiotic use and postoperative infection rates were established. During the second year, computer-generated reminders regarding perioperative antibiotic use were placed in the patient's medical record prior to surgery and patterns of antibiotic use and postoperative wound infections monitored. Hospitalized patients undergoing non-emergency surgery from June to November 1985 (3,263 patients), and from June to November 1986 (3,568) were monitored with respect to indications for perioperative antibiotic use, timing of antibiotic use and postoperative infectious complications. Perioperative antibiotic use was considered advisable for 1,621 (50%) patients in the 1985 sample and for 1,830 (51%) patients in the 1986 sample. Among these patients, antibiotics were given within two hours before the surgical incision in 638 (40%) of the 1985 sample and 1,070 (58%) of the 1986 sample (p less than 0.001). Overall, postoperative wound infections were detected in 28 (1.8%) of 1,621 patients in 1985 compared with 16 (0.9%) of 1,830 such patients in 1986 (p less than 0.03). We conclude that computer-generated reminders of perioperative antibiotic use improved prescribing habits with a concurrent decline in postoperative wound infections.

Anti-Bacterial Agents

Serious Pseudomonas infections associated with endoscopic retrograde cholangiopancreatography.

After observing a single case of Pseudomonas aeruginosa bacteremia following endoscopic retrograde cholangiopancreatography (ERCP), six other P. aeruginosa infections that were temporally related to ERCP were retrospectively found over one year (August 1985 through July 1986) at LDS Hospital. In all seven patients, infection developed within five days after an ERCP. Five patients had bacteremia and two had cholangitis. All five of the Pseudomonas isolates available for testing were serotype 010. Cultures from the ERCP endoscope and several other endoscopes also yielded P. aeruginosa serotype 10, as did environmental cultures from equipment used to clean endoscopes. Among 167 ERCPs performed during the outbreak period, no other patient acquired P. aeruginosa infection. Each of the patients in the outbreak received the first scheduled ERCP of the day. The mean duration between the cleaning of the ERCP endoscope and its subsequent use was significantly longer in cases than in matched controls, a factor that may have permitted contaminating organisms to achieve high inocula in the inadequately cleaned endoscope. Epidemic control measures included improved disinfection of endoscopes, ongoing surveillance, and appropriate antimicrobial prophylaxis. This experience suggests that exogenous infection with Pseudomonas is associated with ERCP, that protracted and insidious outbreaks may occur, and that the occurrence of even a single case of Pseudomonas infection after ERCP should stimulate an epidemiologic investigation.

Cholangiopancreatography, Endoscopic Retrograde

Bringing HELP to the clinical laboratory--use of an expert system to provide automatic interpretation of laboratory data.

In domains where the types of data which are to be interpreted are relatively constrained (as in the case of specific laboratory test results), our modular data-driven approach can be very productive and well received by the clinical recipient of the data. The computer rarely surpasses the knowledge of an experts result from lack of communication, imperfect memory, oversight or multiple decision-makers caring for the same patient. In such cases, most of the alerts are immediately recognized as valid, so the need for elaborate explanations is not a high priority. On the other hand, a non-specialist is alerted to the need for additional investigation, tests or collaborative support, by the fact that a reminder or diagnosis that s/he had not previously considered, appears. In other words, for the expert, a data-driven system provides unceasing oversight in high-volume low-yielded situations where a small number of mistakes may uncommonly occur for reasons which are not related to the lack of knowledge of the provider. For the non-specialist the system suggests that the patient may have problems in a domain for which the physician needs additional support. In the present state of the art, we do not think that total reliance on the computer-contained knowledge is the ultimate source of this additional support; providing the awareness of the need may be the most important contribution. Once you know that you need help, it is usually obtainable. In a discussion about how computer systems have failed, Friedman and Gustafson made the following observation.(ABSTRACT TRUNCATED AT 250 WORDS)

Decision Making, Computer-Assisted

Adapting disease-specific isolation guidelines to a hospital information system.

The authors modified the Centers for Disease Control's guideline for disease-specific isolation precautions to a hospital computerized information system. Entering a suspected diagnosis selected from the isolation option on computer terminals generated: a printout listing the isolation instructions, infective material(s), and persons who should avoid exposure; an order for the appropriate supplies; a patient charge based on the supplies required; and an option for stopping, changing, or listing the orders. In order to implement this system, both extensive in-service training for nurses and efforts to change ordering practices of physicians were necessary. Prevalence surveys before and after computerization were used to evaluate the new system. Combined surveys showed that isolation was ordered for only 21% of patients when indicated. Failure to isolate was identified as a significant problem. As a consequence, continuous surveillance and consultation of all infected patients were instituted, resulting in isolation orders for 81% when indicated. The computerized disease-specific system has resulted in better and more accurate use of isolation, probably due to in-service education and surveillance efforts.

Centers for Disease Control and Prevention, U.S.

Development of a computerized infectious disease monitor (CIDM).

At the LDS Hospital in Salt Lake City, an interface was developed between the microbiology laboratory computer system and the HELP integrated central hospital computer system. The HELP system includes medical information from most clinical care support areas. The microbiology data are translated from the laboratory computer file structure to a hierarchical data structure on the HELP system. A knowledge base was created with the help of infectious disease experts, and became part of a Computerized Infectious Disease Monitoring system (CIDM). The knowledge base is automatically activated when specific microbiology data are entered into a patient's computer file (data driven), thus decisions are made automatically with no additional effort required of medical personnel. The CIDM was designed to inform infectious disease personnel when a patient has one of the following conditions: a hospital-acquired infection, an infection at a normally sterile body site, an infection due to a bacteria with an unusual antibiotic sensitivity pattern, an infection for which the patient is not receiving an antibiotic to which the offending bacteria is sensitive, an infection that could be treated with a less expensive antibiotic, an infection which is required by law to be reported to state and national health authorities, and those patients receiving prophylactic antibiotics longer than is medically indicated. All of the microbiology data are now extensively reviewed by nurses and physicians from terminals at nursing stations or intensive care units. The CIDM is currently being used for hospital-acquired infection surveillance at LDS Hospital.

Anti-Bacterial Agents

Life history and habitat analysis of the eye fluke Diplostomum spathaceum (trematoda: diplostomatidae) in Utah.

Diplostomum spathaceum which is widespread throughout Utah in desert, mountain valley, and high alpine lakes, causes a disease known as diplostomatosis or eye fluke disease. Snails (756) were examined and two species, Lymnaea stagnalis and L. palustris were positive for D. spathaceum. Examination of 838 fish, which included 19 species, revealed 10 species (Salmo trutta, Catostomus discobulus, Salmo clarki, Micropterus salmoides, Catostomus platyrhynchus, Salmo gairdneri, Gila atraria, Catostomus ardens, Salvelinus fontinalis, and Richardsonius balteatus) positive for metacercariae of D. spathaceum. The only avian hosts positive for adult Diplostomum were Larvus californicus and L. delawarensis.

Animals