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D C Classen

Publications and source records attributed to D C Classen.

At least 19 recordsLinked to original sources

A computer-assisted management program for antibiotics and other antiinfective agents.

BACKGROUND AND METHODS: Optimal decisions about the use of antibiotics and other antiinfective agents in critically ill patients require access to a large amount of complex information. We have developed a computerized decision-support program linked to computer-based patient records that can assist physicians in the use of antiinfective agents and improve the quality of care. This program presents epidemiologic information, along with detailed recommendations and warnings. The program recommends antiinfective regimens and courses of therapy for particular patients and provides immediate feedback. We prospectively studied the use of the computerized antiinfectives-management program for one year in a 12-bed intensive care unit. RESULTS: During the intervention period, all 545 patients admitted were cared for with the aid of the antiinfectives-management program. Measures of processes and outcomes were compared with those for the 1136 patients admitted to the same unit during the two years before the intervention period. The use of the program led to significant reductions in orders for drugs to which the patients had reported allergies (35, vs. 146 during the preintervention period; P<0.01), excess drug dosages (87 vs. 405, P<0.01), and antibiotic-susceptibility mismatches (12 vs. 206, P<0.01). There were also marked reductions in the mean number of days of excessive drug dosage (2.7 vs. 5.9, P<0.002) and in adverse events caused by antiinfective agents (4 vs. 28, P<0.02). In analyses of patients who received antiinfective agents, those treated during the intervention period who always received the regimens recommended by the computer program (n=203) had significant reductions, as compared with those who did not always receive the recommended regimens (n= 195) and those in the preintervention cohort (n = 766), in the cost of antiinfective agents (adjusted mean, $102 vs. $427 and $340, respectively; P<0.001), in total hospital costs (adjusted mean, $26,315 vs. $44,865 and $35,283; P<0.001), and in the length of the hospital stay days (adjusted mean, 10.0 vs. 16.7 and 12.9; P<0.001). CONCLUSIONS; A computerized antiinfectives-management program can improve the quality of patient care and reduce costs.

Anti-Bacterial Agents

Oral antimicrobial prophylaxis in bone marrow transplant recipients: randomized trial of ciprofloxacin versus ciprofloxacin-vancomycin.

The optimal oral antimicrobial prophylactic regimen for bone marrow transplant recipients remains to be elucidated. We randomized 84 patients to receive either oral ciprofloxacin or ciprofloxacin plus vancomycin at hospital admission. Patients were monitored for bacteremias and clinical parameters, and stool and throat swab surveillance cultures were performed. The addition of vancomycin resulted in a significant decrease in the frequency of patients with surveillance cultures positive for coagulase-negative staphylococci (stool cultures, 44 versus 23%; throat swab cultures, 37 versus 19%) and alpha-hemolytic streptococci (throat swab cultures, 90 versus 60%). The frequencies of positivity for Candida spp. and gram-negative organisms on surveillance cultures were comparable. Despite these results, no differences in the incidences of bacteremias (12 of 41 versus 12 of 43 patients) or clinical parameters such as number of days to first fever, total number of febrile days, length of stay, and number of transfusions could be demonstrated. Because of a lack of efficacy of vancomycin and emerging problems with vancomycin-resistant isolates, vancomycin should not be used in oral antimicrobial prophylaxis regimens.

Antibiotic Prophylaxis

Association of borderline oxacillin-susceptible strains of Staphylococcus aureus with surgical wound infections.

Staphylococcus aureus isolates which produce type A staphylococcal beta-lactamase have been associated with wound infections complicating the use of cefazolin prophylaxis in surgery. To further evaluate this finding, 215 wound isolates from 14 cities in the United States were characterized by antimicrobial susceptibility and beta-lactamase type and correlated with the preoperative prophylactic regimen. Borderline-susceptible S. aureus isolates of phage group 5 (BSSA-5), which produce large amounts of type A beta-lactamase and exhibit borderline susceptibility to oxacillin, comprised a greater percentage of the 120 wound isolates associated with cefazolin prophylaxis than they did of the 95 isolates associated with other prophylactic regimens (25% versus 12.6%, respectively; P < 0.05). In contrast, methicillin-resistant S. aureus isolates were distributed evenly between the two groups (8.3% versus 11.6%, respectively). In vitro assays demonstrated that cefazolin was hydrolyzed faster by BSSA-5 strains than by other beta-lactamase-producing, methicillin-susceptible strains (1.54 versus 0.50 microg/min/10(8) CFU, respectively; P < 0.0001). These data demonstrate that BSSA-5 strains are a distinct subpopulation of methicillin-susceptible S. aureus which frequently cause deep surgical wound infections. Cefazolin use in prophylaxis is a risk factor for BSSA-5 infection.

Cefazolin

Infectious diseases consultation: impact on outcomes for hospitalized patients and results of a preliminary study.

In the absence of detailed and specific data on outcomes, specialists are thought to contribute excessively to the cost of care. Infectious diseases physicians are at further risk of heavy utilization of medical resources because their patients often are those with serious complications or expensive underlying diseases (e.g., AIDS). By using readily available information in a sophisticated computer database, we examined the crude economic impact of an inpatient infectious diseases consultation and identified important matching variables for more refined analysis. The study was performed at LDS Hospital (Salt Lake City), a tertiary care facility with four full-time infectious diseases physicians. A total of 496 cases (patients who were seen by an infectious diseases consultant) were matched with 3,117 controls (patients who were not seen by an infectious diseases consultant). Matching was performed on the basis of age, sex, exact discharge diagnosis-related group, minimum length of hospital stay equal to the interval from admission to consultation for cases, and measures of the severity of illness (nursing acuity score and the number of secondary diagnoses). Cases had longer lengths of hospital stays, longer intensive care unit lengths of stays, and higher antibiotic costs than did matched controls, and if the consultation occurred in the last one-third of hospitalization, cases had shorter lengths of hospital stay and lower antibiotic costs than did controls.

Case-Control Studies

Implementing antibiotic practice guidelines through computer-assisted decision support: clinical and financial outcomes.

OBJECTIVE: To determine the clinical and financial outcomes of antibiotic practice guidelines implemented through computer-assisted decision support. DESIGN: Descriptive epidemiologic study and financial analysis. SETTING: 520-bed community teaching hospital in Salt Lake City, Utah. PATIENTS: All 162 196 patients discharged from LDS Hospital between 1 January 1988 and 31 December 1994. INTERVENTION: An antibiotic management program that used local clinician-derived consensus guidelines embedded in computer-assisted decision support programs. Prescribing guidelines were developed for inpatient prophylactic, empiric, and therapeutic uses of antibiotics. MEASUREMENTS: Measures of antibiotic use included timing of preoperative antibiotic administration and duration of postoperative antibiotic use. Clinical outcomes included rates of adverse drug events, patterns of antimicrobial resistance, mortality, and length of hospital stay. Financial and use outcomes were expressed as yearly expenditures for antibiotics and defined daily doses per 100 occupied bed-days. RESULTS: During the 7-year study period, 63 759 hospitalized patients (39.3%) received antibiotics. The proportion of the hospitalized patients who received antibiotics increased each year, from 31.8% in 1988 to 53.1% in 1994. Use of broad-spectrum antibiotics increased from 24% of all antibiotic use in 1988 to 47% in 1994. The annual Medicare case-mix index increased from 1.7481 in 1988 to 2.0520 in 1993. Total acquisition costs of antibiotics (adjusted for inflation) decreased from 24.8% ($987,547) of the pharmacy drug expenditure budget in 1988 to 12.9% ($612,500) in 1994. Antibiotic costs per treated patient (adjusted for inflation) decreased from $122.66 per patient in 1988 to $51.90 per patient in 1994. Analysis using a standardized method (defined daily doses) to compare antibiotic use showed that antibiotic use decreased by 22.8% overall. Measures of antibiotic use and clinical outcomes improved during the study period. The percentage of patients having surgery who received appropriately timed preoperative antibiotics increased from 40% in 1988 to 99.1% in 1994. The average number of antibiotic doses administered for surgical prophylaxis was reduced from 19 doses in the base year to 5.3 doses in 1994. Antibiotic-associated adverse drug events decreased by 30%. During the study, antimicrobial resistance patterns were stable, and length of stay remained the same. Mortality rates decreased from 3.65% in 1988 to 2.65% in 1994 (P < 0.001). CONCLUSIONS: Computer-assisted decision support programs that use local clinician-derived practice guidelines can improve antibiotic use, reduce associated costs, and stabilize the emergence of antibiotic-resistant pathogens.

Anti-Bacterial Agents

A large randomized clinical trial of a silver-impregnated urinary catheter: lack of efficacy and staphylococcal superinfection.

PURPOSE: The antibacterial activity of silver-containing compounds has recently been employed in constructing medical devices, such as vascular and urinary catheters, that may be effective in blocking infection. The present study was designed to evaluate the efficacy of a silver oxide-coated urinary catheter. PATIENTS AND METHODS: A total of 1,309 hospitalized patients who required placement of an indwelling urinary catheter for 24 hours or longer were randomly assigned to receive either a silicone catheter coated externally with 5% silver oxide or a standard silicone elastomer-coated latex catheter. Daily catheter-urine specimens were collected aseptically and catheter-care violations were monitored daily for the duration of the catheterization. RESULTS: Bacteriuria developed in 85 of 745 patients (11.4%) in the silver-coated catheter group and in 73 of 564 patients (12.9%) in the control group (P = 0.45). In women who did not receive antibiotics, the rates were 29.3% and 30.4%, respectively (P = 0.98). In men who did not receive antibiotics, the rate of bacteriuria was significantly higher with the silver-coated catheter (29.4% compared to 8.3%, respectively, P = 0.02). Staphylococcal species were isolated more often from the silver-coated catheter group than from the control group (25% versus 8% of all isolates, respectively, P = 0.002). CONCLUSIONS: This study, the largest ever reported evaluating any silver-impregnated device, has not only failed to demonstrate the efficacy of silver in prevention of catheter-associated bacteriuria, as suggested in prior studies, but it has also shown a significantly increased incidence of bacteriuria in male patients and a significantly increased occurrence of staphylococcal bacteriuria. These results suggest the need for caution and for similar large-scale trials before silver-containing compounds are widely used for preventing device-associated infections, both in vascular and urinary catheters.

Bacteriuria

The computer-based patient record: the role of the hospital epidemiologist.

Despite advances in computers and software for data analysis, hospital epidemiologists still must use manual methods for data collection. To automate infection control surveillance fully, healthcare institutions need computerized medical records; however, very few institutions currently have such a system. Healthcare institutions appreciate the need for automation, but frequently do not see a clear path to the desired outcome. In this article, we outline the important issues that hospital epidemiologists must understand if they wish to help their institutions to computerize their medical records.

Hospital Information Systems

Candidal brain abscess associated with vascular invasion: a devastating complication of vascular catheter-related candidemia.

We describe a patient who developed Candida albicans brain abscess associated with prominent vascular invasion following an episode of central venous catheter-related fungemia. The increasing population of immunosuppressed patients and the frequent use of broad-spectrum antimicrobials, corticosteroids, chemotherapeutics, organ transplantation, and prolonged supportive measures are responsible for an increasing incidence of candidal infections. Brain abscess is a rare complication of candidemia but may be expected to become more common as venous catheter-related fungemia is encountered more frequently.

Amphotericin B

Rheumatic pneumonia: reappearance of a previously recognized complication of acute rheumatic fever.

The clinical diagnosis of acute rheumatic fever (ARF) may be challenging; however, a constellation of signs including new valvular insufficiency, cardiomegaly, and heart failure should readily prompt consideration of the diagnosis of rheumatic carditis. In addition, pulmonary findings are compatible with ARF, as associated pulmonary involvement may represent rheumatic pneumonia. We report the case of a young man with ARF and rheumatic pneumonia, a previously described but rare complication of ARF.

Adult

A decision support tool for antibiotic therapy.

We developed a decision support tool to assist physicians anticipating the need for antibiotic therapy. The initial screen alerts physicians of pertinent patient information, provides direct access to other essential medical information, and stimulates clinical judgment by suggesting an antibiotic regimen. The decision support tool also suggests the dose and interval for any ordered antibiotics selected by the physicians. During a 7-month pilot study, all antibiotics for patients admitted to the Shock/Trauma/Respiratory Intensive Care Unit (STRICU) were ordered using the decision support tool. Clinical data from the study period and a 12-month control period (the previous year) were collected and compared. The decision support tool was used to order antibiotics 588 times during the study period and the suggested antibiotics were used 218 (37%) times. The computer suggested dosages were used over 90% of the time. The mean cost of antibiotics was $87.00 (p < 0.04) less per patient during the study period as compared to the control period. Prospective assessment revealed only 3 antibiotic adverse drug events (ADEs) (0.9%) among 336 study patients as compared to 15 ADEs (2.4%) among 626 control patients (p = 0.164).

Anti-Bacterial Agents

Improving empiric antibiotic selection using computer decision support.

BACKGROUND: Physicians frequently need to start antibiotic therapy before the results of bacterial cultures and antibiotic susceptibility tests are available. We developed and evaluated a computerized antibiotic consultant to assist physicians in the selection of appropriate empiric antibiotics. METHODS: We used a two-stage random-selection study to compare antibiotics suggested by the antibiotic consultant with 482 associated antibiotic susceptibility results and the concurrent antibiotics ordered by physicians. The antibiotics ordered by randomized physicians were then compared between crossover periods of antibiotic consultant use. RESULTS: The antibiotic consultant suggested an antibiotic regimen to which all isolated pathogens were shown to be susceptible for 453 (94%) of 482 culture results, while physicians ordered an antibiotic regimen to which all isolated pathogens were susceptible for 369 culture results (77%) (P < .001). The physicians who prescribed antibiotics to which all pathogens were susceptible did so a mean of 21 hours after the culture specimens were collected. Physicians ordered appropriate antibiotics within 12 hours of the culture collection significantly more often when they had use of the antibiotic consultant than during the period before use (P < .035). Moreover, 88% of the physicians stated they would recommend the program to other physicians, 85% said the program improved their antibiotic selection, and 81% said they felt use of the program improved patient care. CONCLUSIONS: Information from computer-based medical records can be used to help improve physicians' selection of empiric antibiotics for infections.

Anti-Bacterial Agents

Information management in infectious diseases: survival of the fittest.

Like all physicians, infectious disease practitioners are concerned and uncertain about their future role as the United States undergoes a major reform of its health care system. Managed care has become the dominant type of health care provided to most patients in the United States, and specialists are increasingly threatened as patient referrals decrease, reimbursements decline, and health care organizations preferentially recruit primary care physicians over specialists. These changes may represent a potential shift in responsibilities and duties for many infectious disease practitioners. The primary role of the infectious disease physician has traditionally been consultative, although many practitioners have organized programs in infection control, hospital epidemiology, and antibiotic management. These programs have become more important as managed care organizations understand the implications of their potential cost savings. The value of these programs will also be significantly enhanced by the ongoing revolution in medical information management that is being driven by computerization. This paper outlines the enlarging role of computerized information management in clinical patient care and its impact on infectious disease practitioners who are increasingly involved in infection control, hospital epidemiology, and antibiotic management programs, as well as in the development of computerized clinical information systems.

Communicable Diseases

Preventing adverse drug events in hospitalized patients.

OBJECTIVE: To use computerized adverse drug event (ADE) surveillance to help identify methods to reduce the number of ADEs in hospitalized patients. DESIGN: Prospective study of 79,719 hospitalized patients during a 44-month period. SETTING: LDS Hospital, a 520-bed tertiary care center affiliated with the University of Utah School of Medicine, Salt Lake City. INTERVENTION: Sequential study periods of at least one year each were compared. In the first period, data were collected but not reported to physicians, pharmacists, or nurses. In the subsequent study periods, three interventions (computerized alerts of drug allergies, standardized antibiotic administration rates, and timely physician notification of all ADEs) were made to reduce the number of type B (allergic or idiosyncratic reactions) and severe ADEs. RESULTS: In the first study period, we identified 56 type B ADEs during 120,213 patient days. During two subsequent study periods that included alerts to physicians of known drug allergies and standardized antibiotic administration rates, 8 type B events were identified during 113,237 patient days and 18 during 107,868 patient days, respectively (p < 0.002). Early notification of physicians of all confirmed ADEs regardless of severity was associated with a significant reduction of ADEs classified as severe from 41 during 113,859 patient days in the first study period to 12 during 103,071 patient days and 15 during 108,320 patient days in two subsequent study periods, respectively (p < 0.001). CONCLUSIONS: Prospective surveillance of computer-based medical records for known drug allergies and appropriate drug administration rates can reduce the number of type B ADEs. Early ADE detection and notification of physicians permit drug and dosage changes that reduce the progression of mild and moderate ADEs to more severe conditions.

Adverse Drug Reaction Reporting Systems

Prospective surveillance of imipenem/cilastatin use and associated seizures using a hospital information system.

OBJECTIVE: To develop computerized methods to monitor and recommend dosage changes for patients treated with excessive dosages of imipenem/cilastatin (I/C) and to determine the incidence of I/C-associated seizures in our patient population. DESIGN: Prospective observational and interventional study of all patients admitted to LDS Hospital and treated with I/C from May 1, 1987, through June 30, 1991. SETTING: LDS Hospital, Salt Lake City, UT, a 520-bed, tertiary care center associated with the University of Utah School of Medicine. PATIENTS: Using a hospital information system we developed computerized algorithms to identify and monitor patients receiving I/C. These algorithms screened the computer-stored medical records of all inpatient admissions for I/C prescription orders. Computer-decision support algorithms estimated the renal function of each I/C-treated patient and provided suggestions when dosages were determined to be excessive. Additional computer-generated alerts identified patients who were receiving anticonvulsants concomitantly with I/C or whose therapy reflected dosage changes in the previous 24 hours. A list of all I/C-treated patients with alerts was reviewed daily by a clinical pharmacist and prescribing physicians were contacted if the computer-generated suggestions were clinically relevant. MAIN OUTCOME MEASURE: The number and characterization of I/C-associated seizures. RESULTS: From May 1, 1987, through June 30, 1991, we prospectively monitored 107,600 patients of whom 1951 were treated with I/C. The following risk factors for I/C-associated seizures were observed in the I/C-treated population: CNS disease (6 percent), seizure disorders (0.6 percent), and abnormal renal function (70 percent). The observational and interventional methods employed in this study resulted in 79 percent of the patients receiving I/C dosages appropriate for their corresponding renal function. During the 50-month study period, we detected four seizures (0.20 percent) in the I/C-treated patients. All 4 patients were receiving I/C dosages that were excessive with respect to their renal function. CONCLUSIONS: Our rate of seizure (0.2 percent) was lower than the 1-2 percent rate reported in the literature despite the fact that more than 70 percent of the patients who received I/C had risk factors for seizure. We believe that appropriate dosing of I/C results in a low rate of associated seizures. Computer-assisted monitoring of I/C dosages in relation to renal function resulted in a reduced incidence of seizures.

Adolescent