Allen B. Kaiser

Antibiotic Prophylaxis in Vascular Surgery

Preoperative and intraoperative antibiotic prophylaxis of infection in peripheral vascular surgery has been widely used although controlled studies have been lacking. A randomized, prospective, double-blind study of cefazolin versus placebo during 565 arterial reconstructive operations was performed at this hospital from February 1976 through August 1977. Among the 462 patients undergoing surgery of the abdominal aorta and lower extremity vasculature, there was a highly significant difference in the infection rates: 6.8% for placebo recipients versus 0.9% for cefazolin recipients (p <.001). Of the 18 infections, four involved vascular grafts and all four graft infections occurred in the placebo group. Over 8% of abdominal wounds of patients receiving placebo became infected versus 1.2% of cefazolin patients (p <.05). Groin wounds were infected infrequently, 1.1% for placebo patients versus none for cefazolin patients. No infections occurred among 103 brachiocephalic procedures. Skin antisepsis was analyzed retrospectively. Infection rates were significantly higher (p <.01) following hexachlorophene-ethanol versus a povidone-iodine skin preparation. Adverse effects of cefazolin were carefully monitored: no rash, phlebitis, or emergence of resistant strains was observed. A brief perioperative course of cefazolin and povidone-iodine skin antisepsis are recommended in vascular reconstructive surgery of the abdominal aorta and lower extremity vasculature.

Aminoglycoside Therapy of Gram-Negative Bacillary Meningitis

The distribution of aminoglycosides in the cerebrospinal fluid (CSF) space was examined after intralumbar, intraventricular, and systemic administration during seven episodes of gram-negative bacillary meningitis. Six episodes were associated with culture proved ventriculitis. Parenteral therapy with gentamicin or tobramycin produced low concentrations of aminoglycoside (less than 1.0 mug/ml) in the lumbar, ventricular, and cisternal CSF. Administration of 5 to 10 mg of aminoglycoside into the lumbar intrathecal space resulted in 27-81 mug/ml in the lumbar CSF, but 0-2.1 mug/ml in the ventricular CSF. In contrast, aminoglycoside administered into the cerebral ventricles produced concentrations in the lumbar CSF of 11.5-27.5 mug/ml and ventricular CSF of 12.8-40 mug/ml. All six episodes treated via the ventricular route resulted in a bacteriologic cure. Intraventricular administration of aminoglycosides offers a reliable means of achieving high aminoglycoside concentrations throughout the subarachnoid space.

The impact of peer management on test-ordering behavior

Context Can simple electronic aids help physicians reduce unnecessary, costly test ordering? Contribution In this interrupted time-series study from a large academic hospital, a committee of peer leaders selected ways to use their care provider order entry (CPOE) system to reduce unnecessary test ordering. Computer prompts questioning repetitive orders for routine tests and unbundling of tests within metabolic panel tests both reduced test orders. Patient readmission rates, length of stay, transfer to intensive care units, and mortality rates remained stable. Implications Peer-designed interventions using CPOE systems can improve provider test-ordering behavior. The Editors Providers of clinical care order excessive tests for hospitalized patients for defensive reasons (1) or ease of access (2) or because they cannot manage the fear of uncertainty (3, 4). Excessive ordering increases the use of technology and adds unnecessary costs to the delivery of health care. Motivated by studies demonstrating substantial variation in testing behaviors among providers (2, 5-14), inappropriate or unnecessary testing (15-23), and test addiction (24-26), investigators over the past decade have tried to impose sustainable limits on diagnostic evaluations. However, many recommended approaches are too time-consuming (27), difficult to scale across an institution (28), counterproductive to training (29), detrimental to clinical decision making (26), or inappropriately intrusive (26). One study suggested that short-term reductions in the amount of testing were not sustainable (30). In a review of various approaches to limit testing, Solomon and colleagues (24) noted that multifaceted interventions are most likely to succeed. The Institute of Medicine (31, 32) and industry leaders (33, 34) recently advocated the use of information systems to improve health care delivery, especially in the area of care provider order entry (CPOE) (35). Several studies document that computer-based reminders (25, 36-38) and just-in-time decision support (39) improve test-ordering practices. Care provider order entry systems also are an effective way to manage and implement change (38, 40) and can be used to reduce variability in provider behavior (41). Citing an alarming increase in the use of expensive or duplicate testing, the Vanderbilt University Medical Center, Nashville, Tennessee, chartered a resource utilization committee (RUC) to reduce variability in laboratory testing, imaging, and formulary use without restricting access to necessary or reasoned inquiry. Members of the committee included many clinical leaders in the institution (Appendix). The committee first identified specific patterns of excessive resource utilization in the hospital and subsequently devised several interventions using CPOE to reduce repetitive testing. The institutional review board approved the study, and the need for informed consent was waived. Methods Study Sample Vanderbilt University Hospital is a 658-bed tertiary care facility that houses 2 floors of the Vanderbilt Childrens Hospital. During the study period (1999 to 2001), more than 10000 orders were placed daily through the use of CPOE systems from 35 of the 37 patient care units; these 35 units cover approximately 600 beds of the hospital. The pediatric and neonatal intensive care units (ICUs) were not using CPOE systems during this interval. The study sample consisted of attending physicians, housestaff, medical students, nurses, advance practice nurses, and other clinical staff at Vanderbilt University Hospital who used CPOE systems. Physicians directly entered 70% of orders, and other members of the patient care team entered the remainder of orders. Care Provider Order Entry Like many systems, our CPOE system processes test orders as follows. First, a provider enters an order with a specified duration of recurrences. Second, the system generates up to 1 week of orders for individual tests. Third, each test is performed as scheduled unless a provider cancels subsequent occurrences. Finally, for recurring orders still active after each week, the software queues up a subsequent week of individual occurrences. Resource Utilization Committee Interventions To determine how and where to intervene, the RUC analyzed past CPOE log files for testing patterns and used bibliographic resources and its own expertise to determine optimal strategies for ordering individual tests. From December 1999 through the study period, during weekly to monthly committee meetings with all RUC members invited, the committee reviewed CPOE summary data that indicated the volume of laboratory, radiology, and cardiology tests that were ordered per month on each hospital ward. This was done prospectively to identify opportunities for intervention and was also done after the intervention to determine effectiveness. (No study intervention described in this paper was changed on the basis of this feedback, although the transition from the first intervention method to the second intervention method was catalyzed by such analysis.) Physician behaviors were not analyzed individually. Simple RUC member consensus after committee discussions determined which interventions to implementinformed by the data, the expertise of the chiefs of the clinical services serving on the RUC (who at times also consulted faculty experts within their departments and the literature), and the informatics faculty members of the RUC (who could speak to feasibility of various proposed CPOE-based interventions). In designing the educational components of the interventions, various RUC members (or their expert faculty designees within their departments) often provided literature-based synopses of evidence that were converted to hypertext markup language (HTML) documents and made available through the CPOE system at ordering time. Individuals creating such documents were responsible for regularly reviewing them to keep their content current. The first RUC intervention was implemented on 5 December 1999 as a broad attempt to reduce open-ended test ordering beyond 72 hours in the future. Each morning, the CPOE system would display a pop-up message that listed orders for scheduled laboratory tests, radiography, and electrocardiography extending beyond 72 hours. The pop-up prompted the provider to choose whether to continue the order, discontinue the order, or defer a decision until later in the day. If the provider chose to continue or discontinue the order, no other provider would receive pop-up reminders about that order until possibly the next day. The second RUC intervention involved several specific ordering constraints. The RUC reasoned that most repetitive orders for routine blood tests, radiology, and electrocardiography could not be justified without an intervening bedside visit. They then developed several specific ordering constraints. First, individual orders were limited to 1 occurrence in a fixed period of time. Second, the metabolic panel was unbundled and could be ordered only as individual components. Third, a graphical display of results from the previous week was placed on the ordering page for frequently ordered serum chemistry tests. This display made it difficult to claim that previous results were unknown at the time when additional tests were ordered. On 20 January 2000, the RUC initiated the second intervention by making all portable chest radiography orders one-time only. Starting on 1 February 2000, electrocardiograms could be ordered only once or twice in 8 hours per individual order. Providers still could order more electrocardiograms or portable chest radiographs by entering additional one-time orders with different start dates and times. On 21 March 2000, the RUC also implemented specific ordering constraints for unbundled components of the serum metabolic panel: Sodium, potassium, chloride, bicarbonate, and glucose tests could be ordered once or at recurring intervals up to hourly but not beyond 24 hours; blood urea nitrogen (BUN) or serum creatinine tests could be ordered only once in 24 hours. Orders for a complete blood count were not constrained during this second intervention period so that the complete blood count test could be used as a control for ordering behavior. Statistical Analysis The RUC examined 2 methods of counting test orders: on the basis of the day tests were first ordered or on the basis of the day tests were intended to occur. Because providers frequently enter orders to discontinue tests, the RUC defined net orders as the number of tests not discontinued before their time of occurrence. Some tests could be ordered as panels, so that a metabolic panel contributed 7 tests (sodium, potassium, chloride, bicarbonate, glucose, BUN, and creatinine tests) to the overall count of ordered component tests, whereas a portable chest radiograph or electrocardiogram counted as 1 test each. The data were evaluated by using interrupted time-series analyses. Patient name, individual ordering provider, and attending physician were not identified as part of the analysis. Each order was assessed in 3 ways to account for all possible outcomes. First, we noted the date that the order was written to determine whether constraining the duration of the order resulted in increased daily ordering. Second, we analyzed the daily number of net orders to approximate the number of ordered tests performed each day. Third, we counted the number of tests resulted in our institutional data repository to determine the actual number of tests performed. We ultimately used orders rather than test results as our primary measure because log file review revealed that net orders for a test closely reflected the actual number of tests performed and because tests ordered during system downtime were not subject to the intervention. The primary outcome was the daily number of new tests ordered and discontinued. Every CPOE order for each targeted test was considered. We ev

Cefoxitin versus erythromycin, neomycin, and cefazolin in colorectal operations. Importance of the duration of the surgical procedure.

Perioperative parenteral cefoxitin was compared with oral erythromycin, neomycin and parenteral cefazolin in a prospective, double-blind, randomized evaluation of 119 patients undergoing colorectal operations. Patients receiving cefoxitin had a higher wound infection rate than patients receiving erythromycin-neomycin-cefazolin (12.5% v 3.2%, respectively, p = .06). A direct correlation existed between the duration of the operation and the infection rate. Cefoxitin prophylaxis was as effective as erythromycin-neomycin-cefazolin in patients undergoing surgical procedures of 4 hours or less (infection rates of 4.8% and 4.0%, respectively). However, for surgical procedures lasting more than 4 hours, 5 of 14 patients (37.5%) receiving cefoxitin developed a wound infection v 0 of 13 patients receiving erythromycin-neomycin-cefazolin (p < .05). It is speculative as to whether frequent two-gram doses of cefoxitin given during the operation would provide prophylaxis equivalent to erythromycin-neomycin-cefazolin.

Low-level colonization of hospitalized patients with methicillin-resistant coagulase-negative staphylococci and emergence of the organisms during surgical antimicrobial prophylaxis.

By use of techniques that have been developed to detect small numbers of methicillin-resistant staphylococci, we cultured samples from the nares and subclavian and inguinal areas of 29 patients before and after cardiac surgery and 10 patients before and after coronary angioplasty. Methicillin-resistant coagulase-negative staphylococci were recovered before the surgical or angioplasty procedure from 74% of patients. The quantitative recovery of methicillin-resistant isolates before cardiac surgery or coronary angioplasty was compared with the number of methicillin-resistant staphylococci detected at the same site 3 days after the procedure. In cardiac surgery patients (who received antibiotic prophylaxis), 17 of the 28 sites (61%) in which low-level colonization with methicillin-resistant strains was detected preoperatively contained high levels of methicillin-resistant staphylococci postoperatively. In contrast, coronary angioplasty patients (who did not receive antibiotic prophylaxis) did not have any of the 14 sites containing low levels of methicillin-resistant strains before angioplasty emerge to harbor high levels of methicillin-resistant staphylococci after angioplasty. Methicillin-resistant coagulase-negative staphylococci from each site in which high levels of methicillin-resistant staphylococci emerged postoperatively were paired with preoperative isolates from the same site. Identical antibiograms and plasmid profile patterns were demonstrated for seven of the pre- and postoperative isolate pairs, suggesting that the high levels of methicillin-resistant coagulase-negative staphylococci detected on the skin or in the nares after cardiac surgery were derived from methicillin-resistant organisms present at the site preoperatively in much smaller numbers. Images

Guidelines for infection control in intravenous therapy.

Abstract Infusion-associated septicemia is an appreciable hazard to the more than 8 million patients who receive intravenous therapy in U.S. hospitals each year. Rigorous infection control measures...

Pyomyositis: Tropical Disease in a Temperate Climate

Two cases of pyomyositis or bacterial abscess of striated muscle in adults are presented. One patient was initially diagnosed as having acute thrombophlebitis of the lower extremity. Computerized tomography was helpful in establishing the correct diagnosis. The other patient presented with a closed compartment syndrome following blunt trauma. Both patients responded to open drainage and antibiotic therapy, although the diagnosis was delayed for over three weeks in one patient. Although common in the tropics, pyomyositis is unusual in the temperate zone. Unfamiliarity with this entity remains the major obstacle to appropriate management.

Effects of performance-based compensation and faculty track on the clinical activity, research portfolio, and teaching mission of a large academic department of medicine

Purpose Academic departments of medicine must compete effectively for extramural research support and access to patients while preserving their teaching mission. There is not much literature describing plausible mechanisms for ensuring success. The authors describe the design, implementation, and testing of a performance-based compensation plan in a department of medicine that is closely linked to the faculty appointment track. Method Over a three-year period, the changes this plan effected in research portfolio, clinical enterprise, and faculty satisfaction as well as the teaching perceptions of students and housestaff were measured. Results The compound annual growth rate (CAGR) for clinical work grew 40% faster after plan implementation. Federal funding increased at a CAGR that was 170% greater than before. The department halved its award rankings at the National Institutes of Health and faculty satisfaction improved compared with the former method of compensation. Faculty who better understood the plan were more satisfied with the conversion. High measures of teaching quality were maintained by faculty with no apparent change in satisfaction among students or housestaff. Conclusions This performance-based compensation plan with its emphasis on the objectives of career orientation and faculty track assignment strengthened the opportunity to grow both clinical productivity and the funded research portfolio.

Purpura fulminans in pneumococcal sepsis: case report and review.

Purpura fulminans is classically defined by ecchymotic skin lesions, fever, and hypotension. The majority of cases occur in association with bacterial sepsis, and disseminated intravascular coagulation (DIC) is usually present. Prompted by our experience with a patient with pneumococcal sepsis and purpura fulminans in whom hypotension was never observed, we evaluated the important parameters of sepsis in reports of this syndrome. 42 additional cases of pneumococcal bacteremia and purpura fulminans were identified. Hypotension was present in only 51%. Although DIC was present in 85% of patients, hypofibrinogenemia was documented in only 26%. By contrast, both hypotension and hypofibrinogenemia are present in the vast majority of patients described with purpura fulminans in association with meningococcal sepsis. These data confirm that hypotension is not a necessary feature of the syndrome of purpura fulminans associated with pneumococcal sepsis and suggest further that qualitative or quantitative differences exist in the DIC cascade of pneumococcal vs meningococcal sepsis.

Use of extracts versus whole-cell bacterial suspensions in the identification of Staphylococcus aureus beta-lactamase variants.

We previously have shown that extracts of S. aureus isolates which produce the recognized serotypes of staphylococcal beta-lactamase (A, B, C, D) differ in the rates at which they hydrolyze selected cephalosporins, exhibiting substrate profiles which are distinctive for each serotype. In an effort to simplify the methods employed in identifying the different staphylococcal beta-lactamases, we evaluated whether distinctive substrate profiles could be obtained by using whole-cell suspensions of 115 beta-lactamase-producing isolates of S. aureus. Compared with extracts from the same strains, the whole-cell bacterial suspensions not only were simpler to prepare but enabled beta-lactamase typing of a higher proportion of the evaluated strains (86 versus 97%, respectively). Furthermore, the use of whole-cell bacterial suspensions enabled the simultaneous quantitation of the beta-lactamase activity exhibited by each strain. Additionally, by comparing the quantitative activity of beta-lactamase-induced and -uninduced preparations of the same strain, induction ratios (i.e., induced/uninduced activity) could be derived, yielding information regarding the regulation of beta-lactamase production by each strain. We believe that the utilization of whole-cell methods, such as those employed in this study, will facilitate the investigation of qualitative and quantitative differences in beta-lactamase production among clinical and reference isolates of S. aureus.