The integration of transabdominal ultrasound simulators into an ultrasound curriculum

Introduction

Simulation is increasingly used throughout medicine. Within ultrasound, simulators are more established for learning transvaginal and interventional procedures. The use of modern high-fidelity transabdominal simulators is increasing, particularly in centres with large trainee numbers. There is no current literature on the value of these simulators in gaining competence in abdominal ultrasound. The aim was to investigate the impact of a new ultrasound curriculum, incorporating transabdominal simulators into the first year of training in a UK radiology academy.

Methods

The simulator group included 13 trainees. The preceding cohort of 15 trainees was the control group. After 10 months, a clinical assessment was performed to assess whether the new curriculum resulted in improved ultrasound skills. Questionnaires were designed to explore the acceptability of simulation training and whether it had any impact on confidence levels.

Results

Trainees who had received simulator-enriched training scored higher in an objective clinical ultrasound assessment, which was statistically significant (p = 0.0463). End confidence scores for obtaining diagnostic images and demonstrating pathology were also higher in the simulation group. All trainees stated that transabdominal simulator training was useful in early training.

Conclusions

This initial study shows that embedded into a curriculum, transabdominal ultrasound simulators are an acceptable training method that can result in improved ultrasound skills and higher confidence levels. Using simulators early in training could allow trainees to master the basics, improve their confidence, enabling them to get more educational value from clinical ultrasound experience while reducing the impact of training on service provision.

Building new hospitals: a UK infection control perspective

Infection control input is vital throughout the planning, design and building stages of a new hospital project, and must continue through the commissioning (and decommissioning) process, evaluation and putting the facility into full clinical service. Many hospitals continue to experience problems months or years after occupying the new premises; some of these could have been avoided by infection control involvement earlier in the project. The importance of infection control must be recognized by the chief executive of the hospital trust and project teams overseeing the development. Clinical user groups and contractors must also be made aware of infection control issues. It is vital that good working relationships are built up between the infection control team (ICT) and all these parties. ICTs need the authority to influence the process. This may require their specific recognition by the Private Finance Initiative National Unit, the Department of Health or other relevant authorities. ICTs need training in how to read design plans, how to write effective specifications, and in other areas with which they may be unfamiliar. The importance of documentation and record keeping is paramount. External or independent validation of processes should be available, particularly in commissioning processes. Building design in relation to infection control needs stricter national regulations, allowing ICTs to focus on more local usage issues. Further research is needed to provide evidence regarding the relationship between building design and the prevalence of infection.

Evaluation of a new chromogenic medium, Uriselect 4, for the isolation and identification of urinary tract pathogens

AIMS

To compare the performance of a new chromogenic medium, Uriselect 4, with cystine lactose electrolyte deficient (CLED) agar and an established chromogenic agar, CPS ID 2 medium, for detection of urinary tract pathogens.

METHODS

Using a semiquantitative culture method, 777 samples were inoculated on to the three test media in duplicate. All bacterial strains that yielded a potentially significant growth were observed for colony colour and identified using standard methods.

RESULTS

Of the 777 samples tested, 589 urine samples yielded potentially significant growth of at least one strain. A total of 811 strains were isolated on at least one of the three media. A total of 168 urine samples yielded a mixture of at least two strains. Uriselect 4 medium showed the best sensitivity of the three media and only failed to recover 14 strains (1.7%). CPS ID 2 medium failed to recover 22 strains (2.7%). CLED medium showed the worst recovery and failed to recover 74 strains (9.1%). Both chromogenic media allowed for identification of Escherichia coli with a high degree of specificity (98% for Uriselect 4, 99.7% for CPS ID 2). Inclusion of a spot indole test increased the specificity of both chromogenic media to 100% for E coli.

CONCLUSIONS

Uriselect 4 and CPS ID 2 were superior to CLED medium for the isolation of urinary tract pathogens mainly because of their ability to discriminate mixed cultures. Both chromogenic media were also useful for the preliminary identification of the most common urinary tract pathogens.

A novel selective medium for the detection of methicillin-resistant Staphylococcus aureus enabling result reporting in under 24 h

A simple selective broth was devised to indicate the presence of methicillin resistant Staphylococcus aureus (MRSA) in clinical samples. The broth comprised nutrient broth supplemented with sodium chloride, ciprofloxacin, colistin and aztreonam as selective agents and also mannitol, trehalose and phenol red as an indicator system. In a preliminary study using 228 clinical samples this selective mannitol broth (SMB) proved to be more sensitive than other selective agars for detection of MRSA within 24 h. In an extended study of a further 1124 clinical samples from 470 randomly selected patients, SMB detected 85.1% of MRSA strains present with a specificity of 43.6%. We conclude that SMB offers a convenient, inexpensive and sensitive method for high-throughput screening for MRSA.

Effect of WBC reduction of transfused RBCs on postoperative infection rates in cardiac surgery

BACKGROUND

WBC-replete blood transfusion has been suggested as an independent cause of increased postoperative infection.

STUDY DESIGN AND METHODS

A total of 597 patients undergoing elective coronary artery or heart valve surgery were randomly assigned to receive plasma-reduced (PR), buffy coat-depleted (BCD), or WBC-filtered (WCF) RBCs in the event of requiring blood transfusion. Details of postoperative course were recorded. Further information was collected from the patient's general practitioner 3 months after discharge.

RESULTS

No significant difference in inpatient infection rates was observed among patients randomly assigned to receive PR, BCD, or WCF RBCs. When only those receiving transfusion were analyzed (n = 509), use of PR RBCs was associated with more events coded as infections (p < or = 0.05) compared with BCD or WCF RBCs. However, when events coded as urinary tract infections were excluded, there was no significant difference among the three groups. Follow-up performed after discharge showed no difference in readmission rates, but a higher reported rate of infection in those randomly assigned to receive WCF RBCs (p < 0.02).

CONCLUSION

No evidence has been found, analyzed by intention to treat, that use of WBC-reduced, BCD, or WCF RBCs reduces postoperative inpatient infection in patients undergoing cardiac bypass surgery.

A mass in the liver

We report a case of alveolar echinococcosis. To our knowledge this is the first report of human alveolar echinococcosis to be confirmed in the UK and if contracted in Afghanistan the first report for that country.

Survival of enterococci during hospital laundry processing

Much remains to be elucidated about the epidemiology of nosocomial enterococcal infections. Enterococci are, however, known to be relatively thermotolerant, and several studies have shown that under laboratory conditions many strains are able to survive the time/temperature combinations of the UK Department of Health recommendations for the decontamination of used linen (HSG(95)18). We therefore wished to investigate the efficacy of decontamination of enterococci from hospital linen in working hospital laundries. The thermotolerance of 40 strains of Enterococcus faecalis and Enterococcus faecium was first determined. Reduction by a factor of greater than 10(5) was achieved in only two of 40 strains after 3 min at 71 degrees C or 10 min at 65 degrees C, the time/temperature combinations specified by the Department of Health for the disinfection of used linen. During experimental challenge of 10 working hospital laundries, however, we demonstrated successful decontamination of laundry artificially contaminated with enterococci. This was shown to take place during the washing stage. Our study suggests that, despite the relative thermotolerance of enterococci, the time/temperature combinations specified in HSG(95)18 should be adequate for their decontamination in hospital laundries.

Evolution of IESs and scrambling in the actin I gene in hypotrichous ciliates

Germ-line (micronuclear) genes in hypotrichous ciliates are interrupted by numerous, short, noncoding, AT-rich segments called internal eliminated segments, or IESs. IESs divide a gene into macronuclear destined segments, or MDSs. IESs are excised from micronuclear genes, and the MDSs are spliced when a micronuclear genome is processed into a macronuclear genome after cell mating. In the micronuclear version of the actin I gene intramolecular recombination between IESs during evolution has put MDSs into a scrambled disorder in some but not all hypotrichs. Studies using rDNA sequences to define phylogenetic relationships among eight hypotrichs suggests that evolution of the micronuclear actin I gene proceeds by successive addition of IESs in earlier diverging species, without MDS scrambling. Continued addition of IESs and recombination among IESs in later diverging species produced actin I genes with scrambled MDSs. Subsequent to MDS scrambling, additional IESs were inserted into the more recently evolved species. Thus, IES insertions and gene scrambling occur in a progressive manner during species evolution to produce micronuclear actin I genes of increasing structural complexity.

Tuberculosis transmitted through transplantation

Tuberculosis in solid organ transplant recipients is associated with relatively high morbidity and mortality and is often extra-pulmonary. Reactivation of dormant infection is the usual mode of acquisition with donor and nosocomial transmission occurring infrequently. We report two cases of probable donor transmitted extra-pulmonary infection where both isolates of Mycobacterium tuberculosis proved to be indistinguishable using hemi-nested inverse PCR of the IS 6110 region.

Alizarin-beta-D-galactoside: a new substrate for the detection of bacterial beta-galactosidase

We describe the synthesis of a new substrate for the detection of bacterial beta-galactosidase. This substrate, alizarin-beta-D-galactoside, is readily hydrolysed to release alizarin which complexes with various metal ions to form brightly coloured chelates. A total of 367 strains of Gram-negative bacteria were examined for their ability to hydrolyse three chromogenic substrates: alizarin-beta-D-galactoside (Aliz-gal), cyclohexenoesculetin-beta-D-galactoside (CHE-gal) and 5-bromo-4-chloro-3-indolyl-beta-D-galactoside (X-gal). A total of 182 strains (49.6%) were found to hydrolyse at least one of the three substrates. All of these 182 strains (100%) hydrolysed Aliz-gal whereas only 170 (93.4%) and 173 (95.1%) hydrolysed CHE-gal and X-gal, respectively. We conclude that alizarin-beta-D-galactoside is a highly sensitive substrate for the demonstration of beta-galactosidase.

Evaluation of tube coagulase and a fluorogenic substrate for rapid detection of methicillin-resistant Staphylococcus aureus from selective enrichment broth in an outbreak of EMRSA 15

We investigated the use of tube coagulase and a fluorescent substrate, N-t-BOC-val-pro-arg-7-amido-4-methylcoumarin for the rapid detection of MRSA in selective broth enrichment cultures during an outbreak. These methods were compared with direct plating of swabs and plating a selective broth enrichment culture using 200 screening swabs collected from forty patients during the investigation of an outbreak of E-MRSA 15. Overall 66 swabs were positive for MRSA following subculture of broth enrichment culture. Direct plating detected 25 (38%) positives, tube coagulase 37 (56%), and fluorescent substrate 49 (74%) respectively, although nine of the 49 turned out to be false reactions. When detection from individual patients was analyzed, selective broth subculture identified 28 patients colonized with MRSA. Direct plating detected only 12 (43%) of these patients. The tube coagulase and fluorescence methods detected MRSA in 17 (60%) and 19 (68%) patients respectively. The tube coagulase method was found to be 100% specific for MRSA suggesting its use as a rapid method for the detection of MRSA from selective enrichment broth.

Outbreak of gram-negative septicaemia caused by contaminated continuous infusions prepared in a non-clinical area

An outbreak of Gram-negative septicaemia due to cross infection on an acute cardiology ward is reported. This outbreak was facilitated by two factors: first, an area originally designed for non-clinical purposes was converted into a clean utility area without consulting the infection control team, and second, changes in staff had taken place at the same time. This outbreak emphasizes the importance of continuous staff training in infection control, the involvement of the infection control team in all building alterations and the need to improve recommendations by the Department of Health in the design of clean utility areas.

Direct milk excretion of Campylobacter jejuni in a dairy cow causing cases of human enteritis

Consumption of milk contaminated with Campylobacter jejuni has been described as a cause of human enteritis. Although faecal contamination of milk with the organism has frequently been described, direct milk excretion of Campylobacter jejuni into milk has rarely been linked with cases of human infection. We describe the investigations undertaken following the isolation of Campylobacter jejuni from samples of unpasteurized milk prior to retail. Results of epidemiological investigations including typing of Campylobacter jejuni isolates using pyrolysis mass spectrometry, Penner and Lior serotyping, biotyping, phage typing and restriction fragment length polymorphism analysis provided convincing evidence implicating direct milk excretion of Campylobacter jejuni by one asymptomatic dairy cow as the source of the milk contamination and the cause of local cases of human enteritis.

Outcome of Toxoplasma gondii mismatches in heart transplant recipients over a period of 8 years

Donor-related infection due to Toxoplasma gondii is a well-recorded complication of cardiac transplantation. In order to assess the efficacy of co-trimoxazole in small doses as prophylaxis for primary Toxoplasma gondii infection in seronegative heart and heart-lung transplant recipients receiving organs from seropositive donors, we reviewed the serostatus and clinical outcome of all such mismatched transplants performed at our unit over a period of 8 years. Of 310 transplants performed between May 1985 and May 1993, donor and recipient serum samples were available for 257 heart and 33 heart-lung transplants. Of these, 13 (4.5%) were toxoplasma mismatches. Post-transplant review serum samples were available for 3 months or longer for nine of the 13 mismatches. The first three patients received co-trimoxazole 480 mg bd orally for 3 months (regimen A) while the remainder received only the standard prophylaxis designed for Pneumocystis carinii i.e., 960 mg bd orally three times per week for 3 months (regimen B). Seroconversion was demonstrated in only one patient (regimen A). Furthermore, none of the mismatched patients developed serious infection compatible with primary toxoplasmosis. We therefore conclude that in centres with a low prevalence of toxoplasma seropositivity, testing of donor and recipient serum for Toxoplasma gondii antibody should be performed only when clinically indicated and, in addition, standard prophylaxis for Pneumocystis carinii may be adequate for preventing primary toxoplasmosis.

A comparison between oral ciprofloxacin and intraperitoneal vancomycin and netilmicin in CAPD peritonitis

This report describes a prospective, randomized comparison of oral ciprofloxacin and intraperitoneal vancomycin/netilmicin in the treatment of 50 consecutive episodes of CAPD peritonitis in 35 patients. Successful cure of peritonitis was achieved in 76% of subjects taking oral ciprofloxacin and 72% of those given intraperitoneal antibiotics. Satisfactory concentrations of ciprofloxacin in dialysate were achieved in all patients. Failure of ciprofloxacin was due to persistence of an isolate of intermediate sensitivity (1), to persistence with acquisition of resistance (1), and to relapse/reinfection in the remaining four cases (with resistant or moderately sensitive strains in three cases). Ciprofloxacin was well tolerated in the majority of cases. A significant rise in serum creatinine was noted in almost all patients taking oral ciprofloxacin. The advantages of oral drug administration indicate that oral ciprofloxacin is the preferred first-line treatment of CAPD-associated peritonitis.