Is the combination of UV-C light and bleach less effective than bleach alone for intensive care unit surface disinfection?

Background: Chlorine-based disinfectants, such as bleach, are commonly used for cleaning in healthcare settings to prevent the transmission of nosocomial pathogens. To enhance the efficacy of disinfection, ultraviolet-C (UV-C) light systems have been proposed to supplement standard cleaning procedures. As bleach decomposes in UV light, we hypothesised that the use of UV-C light as an adjunct to manual cleaning with bleach, may decrease the efficacy of disinfection instead. Methods: In the laboratory, stainless steel sheets and plastic keyboards were inoculated with Pseudomonas aeruginosa (∼106 CFU/ml) and subjected to treatment with either UV-C light only, bleach only or a combination of UV-C light and bleach. The residual bioburden (CFU/ml) was quantified through conventional microbiological techniques. Results were compared to non-exposed control surfaces and against each treatment strategy. Results: On tested surfaces, there were statistically significant reductions in P. aeruginosa when surfaces were treated with UV-C light only (>2.5 log10 reduction), bleach only (>5.6 log10 reduction) and a combination of UV-C light and bleach (>6.3 log10 reduction) compared to positive control (P < 0.001, all treatment strategies). No significant differences were observed when surfaces were treated with the addition of UV-C light to bleach compared to treatment with bleach alone. Conclusion: There was no difference in the efficacy of disinfection against P. aeruginosa with the combined treatment strategy of UV-C light and bleach compared to bleach alone under laboratory conditions. Further studies are warranted to elucidate the effectiveness of this technology on other healthcare-associated pathogens.

Face Coverings, Aerosol Dispersion and Mitigation of Virus Transmission Risk.

The SARS-CoV-2 virus is primarily transmitted through virus-laden fluid particles ejected from the mouth of infected people. Face covers can mitigate the risk of virus transmission but their outward effectiveness is not fully ascertained. Objective: by using a background oriented schlieren technique, we aim to investigate the air flow ejected by a person while quietly and heavily breathing, while coughing, and with different face covers. Results: we found that all face covers without an outlet valve reduce the front flow through by at least 63% and perhaps as high as 86% if the unfiltered cough jet distance was resolved to the anticipated maximum distance of 2-3 m. However, surgical and handmade masks, and face shields, generate significant leakage jets that may present major hazards. Conclusions: the effectiveness of the masks should mostly be considered based on the generation of secondary jets rather than on the ability to mitigate the front throughflow.

Deaths involving methylenedioxypyrovalerone (MDPV) in Upper East Tennessee.

Two deaths involving 3, 4-methylenedioxypyrovalerone (MDPV) are reported. MDPV is a synthetic cathinone stimulant found in "bath salts" with neurological and cardiovascular toxicity. Biological specimens were analyzed for MDPV by GC/MS and LC/MS. A White man was found dead with signs of nausea and vomiting after repeatedly abusing bath salts during a weekend binge. Femoral venous blood and urine had MDPV concentrations of 39 ng/mL and 760 ng/mL. The second fatality was a White man with a history of drug and bath salt abuse found dead at a scene in total disarray after exhibiting fits of anger and psychotic behavior. Femoral venous blood and urine had MDPV concentrations of 130 ng/mL and 3800 ng/mL. The blood and urine MDPV concentrations are within the reported recreational concentration ranges (blood 24-241 ng/mL and urine 34-3900 ng/mL). Both decedents' deaths were attributed to relevant natural causes in a setting of MDPV abuse.

Survival from profound metabolic acidosis due to hypovolaemic shock. A world record?

This case describes the unexpected survival of an adult man who presented to the emergency department with hypovolaemic shock secondary to a splenic haemorrhage. Before surgery he had a pH 6.527, base excess (BE) -34.2 mmol/l and lactate 15.6 mmol/l. He underwent a splenectomy after which his condition stabilised. He was managed in the intensive care unit postoperatively where he required organ support including renal replacement therapy but was subsequently discharged home with no neurological or renal deficit. Although there are case reports of patients surviving such profound metabolic acidosis these have mainly been cases of near drowning or toxic alcohol ingestion. To the best of our knowledge this is the first reported case of survival after a pH of 6.5 secondary to hypovolaemic shock.

Surgical airway in emergency department intubation.

OBJECTIVES: To determine the frequency of and primary indication for surgical airway during emergency department intubation. METHODS: Prospectively collected data from all intubations performed in the emergency department from January 1999 to July 2007 were analysed to ascertain the frequency of surgical airway access. Original data were collected on a structured proforma, entered into a regional database and analysed. Patient records were then reviewed to determine the primary indication for a surgical airway. RESULTS: Emergency department intubation was undertaken in 2524 patients. Of these, only five patients (0.2%) required a surgical airway. The most common indication for a surgical airway was trauma in four of the five patients. Two patients had attempted rapid sequence induction before surgical airway. Two patients had gaseous inductions and one patient received no drugs. In all five patients, surgical airway was performed secondary to failed endotracheal intubation attempt(s) and was never the primary technique used. CONCLUSION: In our emergency department, surgical airway is an uncommon procedure. The rate of 0.2% is significantly lower than rates quoted in other studies. The most common indication for surgical airway was severe facial or neck trauma. Our emergency department has a joint protocol for emergency intubation agreed by the Departments of Emergency Medicine, Anaesthesia and Critical Care at the Edinburgh Royal Infirmary. We believe that the low surgical airway rate is secondary to this collaborative approach. The identified low rate of emergency department surgical airway has implications for training and maintenance of skills for emergency medicine trainees and physicians.

Recovery from sedation with remifentanil and propofol, compared with morphine and midazolam, for reduction in anterior shoulder dislocation.

OBJECTIVE: To compare recovery from sedation using remifentanil and propofol with our standard regimen of morphine and midazolam for closed reduction in shoulder dislocation in an ED. METHODS: We randomised 40 patients for closed shoulder reduction to receive either remifentanil and propofol (R&P) (20 patients) or morphine and midazolam (M&M) (20 patients). A suitably trained ED doctor gave the sedation. R&P patients received oxygen from a tight-fitting facemask and Mapleson C circuit to prevent hypocapnia and thus reduce the risk of apnoea. Shoulder reduction was performed by another doctor with an ED nurse also present. We noted recovery times, pain and sedation scores, operative conditions, additional medication and adverse events. RESULTS: All patients given remifentanil and propofol had recovered within 30 min in contrast to the morphine and midazolam group where 17 of 20 patients had recovered after 60 min, the remainder requiring a total of 90 min. Median recovery times were 15 min (95% CI 15 to 20) for the remifentanil and propofol group, and 45 min (95% CI 29 to 48) for the morphine and midazolam group. Reduction conditions and scores for pain/distress did not differ between the groups. Seven patients required additional sedation (four R&P, three M&M) to enable shoulder reduction. Five patients (three R&P, two M&M) had received analgesia prior to the procedure from the ambulance service (one R&P, one M&M) and ED (two R&P). Two patients given morphine and midazolam required flumazenil to counter oversedation. CONCLUSIONS: Remifentanil and propofol reduces patient recovery time and provides equivalent operating conditions compared with morphine and midazolam for the reduction of anterior glenohumeral dislocation.

Behavioural mechanisms affecting energy regulation in mice prone or resistant to diet- induced obesity.

We investigated inbred SWR/J and AKR/J mice, two established models for different susceptibility to diet-induced obesity (DIO), to scrutinize the contribution of physical activity and energy assimilation to the etiology of developing obesity. Body mass gain and body composition of mice fed a high-energy (HE) or a low caloric control diet were monitored. In parallel, assimilated energy, locomotor activity and thermoregulatory behaviour were measured. Activity was continuously registered by radio telemetry and, in addition, Open Field (OF) behaviour was used as a quick screening tool for spontaneous activity before and after the feeding trial. Energy assimilation was increased in both strains on HE (AKR/J: +60.7% and SWR/J: +42.8%) but only in AKR/J, body mass (+8.1%) and fat mass (+40.7%) were significantly elevated. As a trend, total home cage activity was increased and was more scattered in SWR/J. Interestingly, HE stimulated OF activity only in SWR/J in the second trial at the end of the feeding experiment. The spatial pattern of OF activity also differed between strains with obese mice avoiding the core area. Under housing conditions, nest building behaviour was more pronounced in AKR/J. To further evaluate OF behaviour as a marker for spontaneous activity an obese mouse line was investigated. Mice lacking the leptin receptor (db/db) showed already before the onset of obesity lowest activity levels in OF. Adjustment of energy intake, higher activity levels and energy consuming thermoregulatory behaviour are mechanisms employed by SWR/J mice to dissipate excess energy as a defence against the onset of obesity. Therefore our results deciphering mechanisms of DIO-sensitivity in mice contribute to the understanding of inter-individual differences in body weight development in an adipogenic environment.

Effect of an integrated care pathway on acute asthma/wheeze in children attending hospital: cluster randomized trial.

OBJECTIVE: To determine whether an integrated care pathway (ICP) could improve care delivered to patients coming to an emergency department only or to patients who were subsequently admitted. STUDY DESIGN: Children (age, 2-16 years; n = 298) coming to the ED with acute asthma/wheeze, were randomized by using a cluster design to either standard care or care delivered by an ICP. RESULTS: Children discharged from the ED who received care with an ICP (n = 118) received more prednisolone (81%; standard, 63%; P = .03) and increased advice to obtain primary care review (72%; standard, 33%; P < .0001). A total of 180 children were admitted (94 ICP, 86 standard). The rate of recovery was unchanged by ICP. The mean ICP length of stay (37.6 hours; range, 33.5-42.4 hours), was 93% of the mean standard length of care (40.7 hours; range, 35.9-46; P = .36). When a discharge checklist was completed (60 of 94 cases), the mean ICP length of stay was 34.2 hours (range, 30.5-38.4 hours; P = .07 versus standard). An ICP resulted in a 30% reduction in prescribing errors (mean, 10.4; standard, 14.8; P = .002). Eighty-four of 94 children with an ICP received a 48-hour discharge plan (89%) versus 35 of 86 children with standard care (41%). More clinical contacts were observed in children receiving care by an ICP (mean, 22, versus standard, 19.2: P = .0004). CONCLUSION: An acute asthma/wheeze ICP improved education and prescribing errors, modestly reduced the length of stay when discharge criteria were adhered to, but did not influence recovery time. Further consideration of the effect on staff workload is required.

Online learning of objects in a biologically motivated visual architecture.

We present a biologically motivated architecture for object recognition that is capable of online learning of several objects based on interaction with a human teacher. The system combines biological principles such as appearance-based representation in topographical feature detection hierarchies and context-driven transfer between different levels of object memory. Training can be performed in an unconstrained environment by presenting objects in front of a stereo camera system and labeling them by speech input. The learning is fully online and thus avoids an artificial separation of the interaction into training and test phases. We demonstrate the performance on a challenging ensemble of 50 objects.

Is the 'LEMON' method an easily applied emergency airway assessment tool?

OBJECTIVE: To assess whether the 'LEMON' method, devised by the developers of the US National Emergency Airway Management Course, is an easily applied airway assessment tool in patients undergoing treatment in the emergency department resuscitation room. METHODS: One hundred patients treated in the resuscitation room of a UK teaching hospital between June 2002 and January 2003 were assessed on criteria based on the 'LEMON' method. RESULTS: All seven criteria of the 'Look' section of the method could be adequately assessed. Data for the 'Evaluate' section could not be obtained in 10 patients, with inter-incisor distance being the most problematical item. The 'Mallampatti' score was unavailable in 43 patients, and had to be assessed in the supine position in 32 of the remaining 57 patients. Assessment for airway 'Obstruction' and 'Neck mobility' could be performed in all patients. CONCLUSION: The 'Look', 'Obstruction' and 'Neck mobility' components of the 'LEMON' method are the easiest to assess in patients undergoing treatment in the emergency department resuscitation room. The 'Evaluate' and 'Mallampatti' components are less easily applied to the population that present to the resuscitation room, and assessment of these is more problematical and prone to inaccuracy. We suggest that the 'LEMON' airway assessment method may not be easily applied in its entirety to unselected resuscitation room patients, and that information on the 'Evaluate' and 'Mallampatti' parameters may not always be available.

Re-thinking approaches to undergraduate health professional education: Interdisciplinary Rural Placement Program.

The Interdisciplinary Rural Placement Program involved the development, implementation and evaluation of a common rural primary health care module. Designed for undergraduate nursing, medical and pharmacy students of the University of Tasmania, students undertook clinical experiences and a collaborative primary health care project at two different Rural Health Teaching Sites across Tasmania. The aim of the project was for interdisciplinary students to work and learn together to enhance their understanding of the cooperative and collaborative nature of professional practice among rural health care workers. This paper will describe the development and implementation of the Interdisciplinary Rural Placement Program and critically discuss the outcomes in relation to nursing. In this paper, three issues will be explored. Firstly, how student nurses questioned their sense of subordination when in fact the level of recognition by their interdisciplinary peers led them to refute this. Secondly, concerns with overcoming the difficulties of coordinating student recruitment and conflicting timetables, while working within existing curricula, will be discussed. The final issue explores the student nurses' recognition that despite inherent tensions and conflict, the need to work as a cohesive and cooperative interdisciplinary team was vital. This project highlighted the challenges that health professions continue to work through in contemporary practice and education sectors. A key recommendation for education providers is that true interdisciplinary education must be achieved through an experiential framework.