Robert A. Larsen

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 patients 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.

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 < 0.001). The average cost of antibiotics received more than 48 hours after the operation was

Development of a computerized infectious disease monitor (CIDM)

42 less per patient in year 2 than in year 1, resulting in a potential cost savings of

Prevention of catheter-associated bacterieuria: Clinical trial of methods to block three known pathways of infection

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.

DAILY MEATAL CARE FOR PREVENTION OF CATHETER-ASSOCIATED BACTERIURIA : RESULTS USING FREQUENT APPLICATIONS OF POLYANTIBIOTIC CREAM

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 patients 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.

The epidemiology and risk factors for nosocomial catheter-associated bacteriuria caused by coagulase-negative staphylococci.

The simultaneous use of methods to block all three known pathways of bacterial entry into the bladders of catheterized patients has been suggested because of the limited effectiveness of individual methods that block single pathways. We conducted a randomized controlled trial to assess the prevention of bacteriuria in patients, using a three-way system that included a hydrophilic polymer-coated and preconnected sealed catheter system, daily catheter care, and disinfection of the outflow tube of the drainage bag with povidone-iodine (i.e., methods to block bacterial entry at the urethral insertion site, at the catheter drainage tube junction, and at the outflow tube). Among treated patients, 14 (4.7%) of 300 acquired bacteriuria as compared with 15 (4.9%) of 306 who did not receive the protocol treatments. Only 3 of 29 episodes of bacteriuria occurred in patients whose meatal cultures did not contain gram-negative bacilli or enterococci; thus migration of bacteria in the periurethral mucous sheath appeared to be the most common pathway by which bacteria gained entry into the bladder in this study. Catheter care and disinfection of the drainage bag outflow tube as used in this study remain unproven methods of preventing catheter-associated bacteriuria. Preconnected catheters with junction seals were used in both treated and untreated patients and, on the basis of previous studies, appear to be effective in reducing junction disconnections and bacteriuria. Therefore we conclude that the use of several simultaneous measures to prevent catheter-associated urinary infections is no more effective than the use of preconnected catheters with junction seals alone and is clearly more expensive.

Computer Surveillance of Hospital-Acquired Infections and Antibiotic Use

OBJECTIVE To determine the efficacy of meatal treatment with a polyantibiotic cream in the prevention of bacteriuria during transurethral bladder catheterization. DESIGN Randomized controlled trial. SETTING Community teaching hospital. PATIENTS Adult patients who underwent closed urinary catheter drainage for short and intermediate durations (two to 30 days). INTERVENTION Polyantibiotic cream containing polymyxin B sulfate, neomycin sulfate, and gramicidin was applied to the urethral meatus-catheter interface three times daily from the first day of catheterization until bacteriuria was found. The onset of bacteriuria was defined as the day the colonizing species first achieved a colony count of greater than or equal to 1000 colonies/ml. Patients randomized to the control group received routine meatal care with cleansing of the meatal surface during daily bathing. RESULTS Among 2,923 patients who were randomly allocated to receive either the protocol meatal care or routine care, the evaluable study population consisted of 747 patients who were nonbacteriuric and who remained catheterized for more than two days. Overall, 26 (6.8%) of 383 patients given the polyantibiotic treatment acquired bacteriuria, as compared to 37 (10.1%) of 364 patients not given this treatment (p = .167). A Cox proportional hazards regression analysis showed that, among putative risk factors including lack of meatal care, only female gender, a meatal swab culture yielding gram-negative rods or enterococci, and lack of antibiotic use during catheterization were independently associated with the development of bacteriuria. CONCLUSIONS The adverse effect of meatal care noted in earlier studies of a disinfectant ointment applied twice daily was not found in this study of an antimicrobial preparation in a cream vehicle applied three times daily. However, the results do not support meatal care as an efficacious method to prevent catheter-associated bacteriuria in all patients.

Randomized Trial of Meatal Care with Silver Sulfadiazine Cream for the Prevention of Catheter-Associated Bacteriuria

Studies of the risk factors for bacteriuria associated with the use of temporary indwelling urinary catheters have focused on gram-negative bacilli and enterococci, the predominant causes of nosocomial urinary tract infection. During a prospective study of 747 catheterized patients, bacteriuria with greater than or equal to 1,000 bacteria/mL were found in 96 patients. Coagulase-negative staphylococci (CNS) accounted for 19% of the episodes of bacteriuria, and S. epidermidis was the most frequent species of CNS. Significant risk factors for bacteriuria were a positive meatal culture for CNS, non-surgical illness, and no antibiotic therapy during catheterization. In contrast to the results of this and earlier studies that females were at greater risk factor for catheter-associated bacteriuria with gram-negative bacilli and enterococci, this was not a risk factor for acquisition of CNS. Possibly this is due to the more similar prevalence of meatal colonization with CNS of males and females compared to the striking difference in prevalence of meatal colonization with gram-negative bacilli and/or enterococci of males and females.