Experiential learning in the animal sciences: development of a multispecies large-animal management and production practicum.

Students enrolled in an introductory animal science course (ASG 3003) at the University of Florida were surveyed (n = 788) over a 3-yr period to ascertain their current experience and career goals in animal agriculture. Sixty-one percent of the students indicated that they were from an urban background. Only 4% were raised on a farm or ranch where the majority of family income was attributed to production agriculture. Eighty-six percent of the students had minimal or no experience working with large domestic farm animals, but nearly 64% of the students wanted to pursue a career in veterinary medicine. Disciplinary and species interests of the students were highly associated with previous background experiences. Students from nonagricultural backgrounds, who were most likely to indicate a career interest involving veterinary medicine, were most interested (P < 0.05) in animal behavior, whereas the students of rural background were more interested (P < 0.05) in animal management. Thirty-three percent of students were primarily interested in small companion animals; 22% in horses; 20% in domestic farm animals, including beef, dairy, swine, or sheep; and 24% in undomesticated zoo animals or wildlife. The career goals indicated by most students necessitate practical application of animal husbandry skills that are often assumed as general knowledge. Thus, a multispecies large animal management and production practicum (ANS 3206) was developed to provide students with hands-on experience. It was an elective course, and students were encouraged to enroll for two consecutive semesters. Teams of students rotated responsibilities among four livestock species (beef, dairy, equine, and swine). Daily responsibilities at each of the units included feeding and monitoring growth of feedlot cattle and finishing swine, farrowing assistance and baby pig processing, and equine training and foaling assistance. Students were also involved with all facets of a working dairy. Additionally, students completed written assignments specific to their individual species responsibilities that included daily journals, worksheets, or calculation of performance measures. Weekly class meetings allowed for instruction and were used to manage the varied course activities. Using a 5-point scale (1 = poor, 5 = excellent), students indicated that the course further stimulated their interest (4.73) and facilitated their learning (4.63) of animal science concepts. Overall course evaluations ranged from 4.54 +/- 0.55 to 4.85 +/- 0.38 over a 4-yr period. As more students enter animal science programs with nonagricultural backgrounds, it will become necessary to reemphasize basic animal-handling skills and practical applications through experiential learning activities.

Management of an outbreak of vancomycin-resistant enterococci in the medical intensive care unit of a cancer center.

Between November 1996 and February 1997, 17 episodes of vancomycin-resistant enterococci (VRE) infection or colonization (9 infections, 8 colonizations), all with the same or a similar genomic DNA pattern, were identified in the medical intensive care unit (MICU) of a tertiary-care cancer hospital. The cases were genotypically traced to a patient who was admitted to the hospital in September 1996 and who, by December 1996, had four different admissions to the MICU. Multifaceted infection control measures, including decontamination of the environment and of nondisposable equipment, halted the nosocomial transmission of VRE in the MICU.

Optimal frequency of changing intravenous administration sets: is it safe to prolong use beyond 72 hours?

OBJECTIVE: To determine the safety and cost-effectiveness of replacing the intravenous (IV) tubing sets in hospitalized patients at 4- to 7-day intervals instead of every 72 hours. DESIGN: Prospective, randomized study of infusion-related contamination associated with changing IV tubing sets within 3 days versus within 4 to 7 days of placement. SETTING: A tertiary university cancer center. PATIENTS AND METHODS: Cancer patients requiring IV infusion therapy were randomized to have the IV tubing sets replaced within 3 days (280 patients) or within 4 to 7 days of placement (232 patients). Demographic, microbiological, and infusion-related data were collected for all participants. The main outcome measures were infusion- or catheter-related contamination or colonization of IV tubing, determined by quantitative cultures of the infusate, and infusion- or catheter-related bloodstream infection (BSI), determined by quantitative culture of the infusate in association with blood cultures in febrile patients. RESULTS: The two groups were comparable in terms of patient and catheter characteristics and the agents given through the IV tubing. Intent-to-treat analysis demonstrated a higher level of tubing colonization in the 4- to 7-day group versus the 3-day group (median, 145 vs 50 colony-forming units; P=.02). In addition, there were three episodes of possible infusion-related BSIs, all of which occurred in the 4- to 7-day group (P=.09). However, when the 84 patients who received total parenteral nutrition, blood transfusions, or interleukin-2 through the IV tubing were excluded, the two groups had a comparable rate of colonization (0.4% vs 0.5%), with no catheter- or infusion-related BSIs in either group. CONCLUSION: In patients at low risk for infection from infusion- or catheter-related infection who are not receiving total parenteral nutrition, blood transfusions, or interleukin-2, delaying the replacement of IV tubing up to 7 days may be safe, as well as cost-effective

Interrelationships in lactating Holsteins of rectal and skin temperatures, milk yield and composition, dry matter intake, body weight, and feed efficiency in summer in Alabama.

Thirty-two lactating, multiparous Holstein cows were utilized in a 91-d experiment in Auburn, Alabama, during summer to determine whether rectal and skin temperatures and respiration rates are repeatable and interrelated and whether whole cottonseed or calcium salts of long-chain fatty acids (Megalac, Church & Dwight Co., Inc., Princeton, NJ) affected milk production or its constituents. Treatments were (I) control, (II) I plus 10.4% whole cottonseed, (III) I plus 2.6% Megalac, and (IV) I plus 5.2% whole cottonseed plus 1.3% Megalac. Data included 358 to 2644 measurements analyzed as a split-plot design of experiment. Only milk protein percentage and protein-to-fat ratio were significantly affected by dietary treatment. Milk protein percentage was depressed by dietary fat additions, especially by the combination of whole cottonseed and Megalac. Within lactation repeatabilities for milk, fat, protein, and SCM yields ranged from 0.44 to 0.66; two percentages and protein to fat ratio, 0.21 to 0.32; feed efficiency, 0.18; dry matter intake (DMI) and body weight, 0.98 and 0.84; rectal and skin temperatures and respiration rate, 0.001 to 0.055. Partial and simple correlations were similar in sign and magnitude. Noteworthy were partial correlations between milk yield and DMI, 0.367; milk yield and rectal temperature, -0.135; milkyield and respiration rate, 0.102. Skin temperature was unrelated to other variables. Respiration rate was correlated with DMI, 0.270. Results should help researchers designing future experiments involving these responses to predict the number of measures needed to detect differences.

Control of nosocomial Clostridium difficile transmission in bone marrow transplant patients.

This is a report of six cases of Clostridium difficile-associated diarrhea (CDAD) that occurred among cancer patients undergoing bone marrow transplantation in a tertiary-care cancer hospital. Specific infection control measures that were taken to minimize the nosocomial spread of CDAD also are discussed.

Infusion therapy team and dressing changes of central venous catheters.

OBJECTIVE: To determine whether central venous catheter (CVC) dressing changes could be performed by ward nurses rather than by the infusion therapy team (ITT) nurses without increasing the risk of catheter-related infection. DESIGN: Retrospective cohort study using prospectively collected data. The study extended from January 1995 to June 1996. SETTING: The University of Texas M.D. Anderson Cancer Center, a referral cancer center. PATIENTS: The study group was a random sample of 483 patients who received CVC dressing changes by ward nurses during the study period. A random sample of 483 patients who received CVC dressing changes by the ITT constituted the control group. RESULTS: The risks of catheter-related septicemia were 1.7% among cases and 1.4% among controls (risk ratio, 1.14; 95% confidence interval [CI95], 0.26-6.42; P=.70). There also were no significant differences between the two groups in the risks of catheter-related site infection (risk ratio, 0.50; CI95, 0.02-4.12; P=.25) or any catheter-related infection (risk ratio=1.00; CI95, 0.27-3.64; P=.59). CONCLUSIONS: Provided that aseptic techniques (including maximal barrier precautions during insertion) are maintained, the responsibility of CVC dressing changes could be delegated to the ward nurses without increasing the low risk of CVC-related infection, resulting in an estimated cost saving in excess of $90,000 per year.

The risk of infection associated with intra-arterial catheters for cancer chemotherapy.

OBJECTIVE: To determine the frequency of, and risk factors for, infections associated with intra-arterial catheters used for cancer chemotherapy. METHODS: Between September 1992 and September 1995, we conducted a surveillance study of all 807 intra-arterial catheters placed for chemotherapy at our center. The insertion site was disinfected with povidone iodine and alcohol, and the arterial catheter was placed using maximal sterile barrier precautions. Upon removal, all intravascular segments were submitted for semi-quantitative culture. RESULTS: No episodes of catheter-related bloodstream infection (95% confidence interval [CI95], 0%-1.6%) were observed. However, the risk of colonization (>15 colony-forming units) of arterial catheters was 15% (CI95, 12%-17%). Retrospective risk-factor analysis conducted on 224 intra-arterial catheters placed for chemotherapy in 1993 showed that colonization was associated significantly with duration of catheterization (median of 1 day for culture-negative catheters vs median of 4 days for culture-positive catheters, P<.001). Age, gender, prior radiotherapy, underlying cancer, neutropenia, and hypoalbuminemia were not associated with catheter colonization. CONCLUSION: Intra-arterial catheters for cancer chemotherapy placed under maximal sterile barrier precautions for a short period of time are associated with a very low risk of bloodstream infection.

Nosocomial respiratory syncytial virus infections: prevention and control in bone marrow transplant patients.

OBJECTIVE: To assess the effectiveness of a multifaceted infection control strategy in limiting the nosocomial transmission of respiratory syncytial virus (RSV) infection to patients in a bone marrow transplant (BMT) unit. DESIGN: Before/after trial. SETTING: University-affiliated tertiary cancer center. PATIENTS: Adult BMT recipients hospitalized during two consecutive wintertime community outbreaks of RSV infection. INTERVENTIONS: An infection control strategy against nosocomial RSV infection was implemented in the BMT unit in February 1993. The strategy involved prompt identification, isolation, and cohorting of RSV-infected patients; prompt therapy with aerosolized ribavirin; use of masks and gloves by anyone entering an infected BMT patient's room; screening visitors for respiratory symptoms; restricting visitation by all children under 12 years of age and all family members and other visitors with RSV symptoms; and restricting symptomatic hospital staff from working in the BMT unit. RESULTS: After implementation of the multifaceted infection-control strategy, there were four cases of nosocomial RSV infection in 3,870 patient days (incidence density, 1.0 case/1,000 patient days) compared with 14 cases of nosocomial RSV infection in 3,152 patient days (incidence density, 4.4 cases/1,000 patient days) during the 1992-1993 RSV season (rate ratio, 4.4; 95% confidence interval [CI95]. 1.4-17.9: P < .01). This decrease in incidence occurred despite a comparable prevalence of community-acquired RSV cases between the two seasons (2.2% vs 3.2% in 1992-1993 and 1993-1994, respectively; prevalence ratio, 0.7; CI95, 0.2-2.1; P = 0.5). CONCLUSION: Institution of a multifaceted infection control strategy significantly reduced the frequency of nosocomial RSV infection in a high-risk group of adult BMT recipients.

Low infection rate and long durability of nontunneled silastic catheters. A safe and cost-effective alternative for long-term venous access.

BACKGROUND: Tunneled central venous catheters (CVCs) and infusion ports have often been considered as the only safe alternative for long-term venous access. The objective of this study was to assess the durability, cost, and infection rate of nontunneled, noncuffed Silastic CVCs. METHODS: We studied a representative cohort of 340 consecutive cancer patients with 359 nontunneled Silastic CVCs inserted and followed up at our center. All patients were evaluated clinically and microbiologically at the time of CVC removal. RESULTS: The mean in-place duration of the catheter for the 359 nontunneled CVCs studied was 109 days (total, 39,147 days of catheter use), and the infection rate was 0.13 per 100 catheter days. When compared with the tunneled Hickman catheter, the insertion cost saving was at least $2322 per CVC. At our institution, the use of nontunneled Silastic catheters with the support of an expert infusion team has resulted in an annual cost saving of at least $7,692,000. Long peripheral CVCs (in the basilic/cephalic vein) had a 26% rate of inflammation at the insertion site compared with only 2.6% for the short subclavian CVCs (P < .01). Most of the exit-site inflammations were sterile, with negative skin and catheter cultures. Neutropenia, bone marrow transplantation, high-dose steroids, and use of vesicant chemotherapeutic agents through the CVC did not predispose the patients to catheter infection. By univariate analysis, acute leukemia was the only risk factor for catheter infection. CONCLUSIONS: Given the low infection rate and long durability of nontunneled silicone CVCs, these catheters could offer a cost-effective and safe alternative to surgically implantable tunneled catheters.

The duration of placement as a predictor of peripheral and pulmonary arterial catheter infections.

To determine the appropriate time for removal or replacement of peripheral and pulmonary arterial catheters in critically ill cancer patients, we prospectively studied 71 peripheral arterial catheters and 71 pulmonary artery (Swan-Ganz) catheters from 110 consecutive cancer patients. All catheters were cultured semiquantitatively, by the roll-plate culture technique. Of the 71 peripheral arterial catheters, 11 (15%) produced local infections (> or = 15 colonies) and four (5.5%) produced catheter-related septicaemia. Ten of the 11 local infections and all four septicaemias occurred after 4 days of catheter placement (P < 0.05). Likewise, of the 71 Swan-Ganz catheters, 12 (17%) produced local infection and four (5.6%) led to septicaemia. Swan-Ganz catheter-related septicaemia occurred at rates of 2% and 16%, before and after 7 days of catheter placement, respectively (P = 0.056). Duration of placement was a risk factor for the development of catheter infections, independent of the patient's neutropenic status, administration of antibiotics such as vancomycin during catheterization, and the presence of concurrent central venous catheters. Life-table analysis showed that the cumulative risks of developing a catheter infection increased from 7% to 17% after 6 days of peripheral arterial catheter placement and from 9% to 18% after 4 days of placement of the Swan-Ganz catheter. We conclude that in the critically ill cancer patient in our unit, peripheral arterial catheters should be changed to a new site every 4-6 days and pulmonary artery catheters every 4-7 days.