'VIOLET': a fluorescence-based simulation exercise for training healthcare workers in the use of personal protective equipment.

BACKGROUND: Healthcare workers caring for patients with high-consequence infectious diseases (HCIDs) require protection from pathogen exposure, for example by wearing personal protective equipment (PPE). Protection is acquired through the inherent safety of the PPE components, but also their safe and correct use, supported by adequate training and user familiarity. However, the evidence base for HCID PPE ensembles and any associated training is lacking, with subsequent variation between healthcare providers. AIM: To develop an evidence-based assessment and training tool for evaluating PPE ensembles and doffing protocols, in the assessment of patients with suspected HCIDs. METHODS: VIOLET (Visualising Infection with Optimised Light for Education and Training) comprises a healthcare mannequin adapted to deliver simulated bodily fluids containing UV-fluorescent tracers. On demand and remotely operated, the mannequin projectile vomits (blue), coughs (red), has diarrhoea (yellow) and is covered in sweat (orange). Wearing PPE, healthcare staff participate in an HCID risk assessment and examination of the 'patient', thereby becoming exposed to these bodily fluids. Contamination of PPE is visualized and body-mapped under UV light before and after removal. Observational findings and participant feedback, around its use as a training exercise, is also recorded. FINDINGS: Significant contamination from different exposure events was seen, enabling evaluation of PPE and doffing procedures used. Observational data and participant feedback demonstrated its strengths and success as a training technique. CONCLUSION: Simulation exercises using VIOLET provide evidence-based assessment of PPE ensembles, and are a valuable resource for training of healthcare staff in wearing and safe doffing of PPE.

Use of ultraviolet-fluorescence-based simulation in evaluation of personal protective equipment worn for first assessment and care of a patient with suspected high-consequence infectious disease.

BACKGROUND: Variations currently exist across the UK in the choice of personal protective equipment (PPE) used by healthcare workers when caring for patients with suspected high-consequence infectious diseases (HCIDs). AIM: To test the protection afforded to healthcare workers by current PPE ensembles during assessment of a suspected HCID case, and to provide an evidence base to justify proposal of a unified PPE ensemble for healthcare workers across the UK. METHODS: One 'basic level' (enhanced precautions) PPE ensemble and five 'suspected case' PPE ensembles were evaluated in volunteer trials using 'Violet'; an ultraviolet-fluorescence-based simulation exercise to visualize exposure/contamination events. Contamination was photographed and mapped. FINDINGS: There were 147 post-simulation and 31 post-doffing contamination events, from a maximum of 980, when evaluating the basic level of PPE. Therefore, this PPE ensemble did not afford adequate protection, primarily due to direct contamination of exposed areas of the skin. For the five suspected case ensembles, 1584 post-simulation contamination events were recorded, from a maximum of 5110. Twelve post-doffing contamination events were also observed (face, two events; neck, one event; forearm, one event; lower legs, eight events). CONCLUSION: All suspected case PPE ensembles either had post-doffing contamination events or other significant disadvantages to their use. This identified the need to design a unified PPE ensemble and doffing procedure, incorporating the most protective PPE considered for each body area. This work has been presented to, and reviewed by, key stakeholders to decide on a proposed unified ensemble, subject to further evaluation.

Diagnostic accuracy and cost analysis of the Alere™ i Influenza A&B near-patient test using throat swabs.

BACKGROUND: Clinical diagnostic sensitivity alone is inadequate in the diagnosis of influenza. Polymerase chain reaction (PCR) testing is sensitive but the inherent delays in result availability potentially prolong time to isolation and treatment. Until recently no near-patient test (NPT) has demonstrated adequate sensitivity for routine clinical use. AIM: To evaluate diagnostic accuracy, time to result availability, clinical impact, and cost consequences of Alere™ i Influenza A&B NPT (Alere Inc., Waltham, MA, USA) using off-label throat swabs. METHODS: Prospective, multi-centre [four UK National Health Service (NHS) hospitals], diagnostic accuracy cohort study with cost modelling. Throat swab samples from suspected influenza patients were tested for influenza using the reference standard of PCR; a second throat swab was tested using NPT. FINDINGS: A total of 827 participants were recruited; 589 were suitable for analysis: sensitivity was 75.8% [95% confidence interval (CI): 67.0-84.6]; specificity was 96.8% (95% CI: 95.2-98.3). Sensitivity varied between Sheffield (Northern General Hospital: 82.1%; Royal Hallamshire Hospital: 83.3%) and other sites (Doncaster Royal Infirmary: 71.4%; Newcastle's Royal Victoria Infirmary: 50.0%) whereas specificity was high (92-100%). Positive predictive value (PPV) was 81.2% (95% CI: 72.9-89.5) with negative predictive value 95.6% (95% CI: 93.9-97.4) with observed prevalence of 15.4%. Median time to result for PCR was 1.1 days (on-site laboratories) and 5.2 days (remote laboratories). Isolation findings: 75% influenza positive not isolated; 69% of isolated participants did not have influenza. For a cohort of 1000 participants, annual estimated non-diagnostic cost savings with NPT are £215,040. CONCLUSION: This first prospective study of the Alere i NPT using throat swabs demonstrates high specificity, high PPV during seasonal epidemics, and rapid result availability which could lead to substantial cost savings.

Chickenpox in adults - clinical management.

Acute varicella zoster virus (VZV) infection, or chickenpox, is still perceived by many as a mild infection of childhood. However, chickenpox is increasingly common in adults and adolescents who together with immunosuppressed individuals are at a higher risk of severe infection. Antiviral therapy is available which both ameliorates symptoms and decreases the severity of chickenpox if administered early in the course of the infection. Passive immunisation with varicella zoster immunoglobulin (VZIG) may prevent or attenuate infection following exposure to varicella of an immunocompromised or pregnant individual or a neonate. Active immunisation is available and is universal in many developed countries. This review reflects current best practice in management of chickenpox in adults by specialist physicians in the UK. The accompanying flowchart has been formulated to guide emergency physicians and general practitioners through the decision-making process regarding treatment and admission for specialist care.

A case of disseminated histoplasmosis successfully treated with the investigational drug posaconazole.

A 79-year-old man with a 3-month history of weight loss and fever was diagnosed with disseminated histoplasmosis. When the infection became refractory to itraconazole therapy, posaconazole was prescribed. The patient became asymptomatic within 1 month of beginning treatment, and his general health improved. Posaconazole was discontinued after 6 months, and the patient has remained well since.

Alopecia in association with severe seborrhoeic dermatitis following combination antiretroviral therapy for acute retroviral syndrome.

We present a case where alopecia occurred with severe seborrhoeic dermatitis associated with the commencement of combination antiretroviral therapy for acute retroviral syndrome. We postulate that the eruption could represent a novel manifestation in association with immunological response to antiretroviral therapy.

The total parenteral nutrition service: an update.

A total parenteral nutrition (TPN) service was established in Oxford in 1978 and the results of the first 3 years were published in 1983. Since then the service has provided intravenous nutritional support to an increasing number of patients, representing a considerable and increasing financial burden on the constrained hospital budget. To assess whether this expansion is justified, and whether regular review has improved the care given to patients, a further audit has been performed for the period 1983 to 1986. Despite an increase of approximately 60% in the numbers of patients parenterally fed, line associated morbidity was less and there were no serious metabolic problems or deaths. Patient selection has improved, as judged by fewer patients fed for periods less than a week. Regular audit appears to improve the selection and treatment of patients but there remains a need to identify subgroups of patients for whom this costly form of nutrition is essential.

Use of a lipid containing medium chain triglycerides in patients receiving TPN: a randomized prospective trial.

Lipid emulsions which contain long chain triglycerides (LCTs) provide a valuable energy source for patients requiring total parenteral nutrition (TPN). We have investigated the use of a new lipid emulsion containing both long and medium chain triglycerides (MCTs) in a randomized prospective trial. Sixty patients received TPN including 500 ml of either 20 per cent Lipofundin S (LCT) or Lipofundin 10 per cent MCT/10 per cent LCT for at least 6 days. Patients with renal or hepatic impairment, or major trauma, were excluded from the study. The MCT/LCT emulsion was found to be as safe and as effective a source of calories as LCT but the differences in metabolic parameters did not differ significantly between the two groups of patients. A lipid emulsion containing MCTs may have important advantages for seriously ill patients, but appears to have no obvious advantages for the majority of patients receiving TPN who are not severely stressed.