Considerations in Mass Casualty and Disaster Management

[Extract] Disasters have increased in frequency over the past century. A number of high profile disasters have also dominated news headlines in the past decade raising the media and community awareness, of disasters. This has been across the full spectrum of disasters and as illustrated in Table 1 has included terrorist bombings, hurricanes, earthquakes, tsunamis and floods

Simple Reaction Time of Ipsilateral and Contralateral Hand to Monaurally Presented Tones of Different Pitch with Binaural White Noise

This study hypothesized that reaction times to monaural auditory stimuli are shorter with the ipsilateral hand than with the contralateral hand under binaural white noise stimulation, and that ipsi- and contralateral reactions do not differ in the absence of white noise. The relationship between the ipsilateral-contralateral reaction time difference and the frequency of the reaction signal was also determined. In experiment I, 10 male undergraduate students each performed 20 ipsilateral and 20 contralateral reactions to each of 6 signal frequencies (400, 800,1200,1600, 2000, 2400 cps) under binaural white noise stimulation. In experiment II, 10 male undergraduate students each performed 20 ipsi- and 20 contralateral reactions, at one stimulus frequency, under white noise on and white noise off conditions. The results support both hypotheses ( p \u3c .001), and also indicate that signal frequency has a significant effect on contralateral reactions· ( p \u3c .001) but not on ipsilateral reactions. Close agreement was obtained with results of other callosal transmission studies, and support provided for the theory that the ear asymmetry effect is caused in part by the occlusion of ipsilateral auditory connections by contralateral ones. The results also suggest that the effect of signal frequency on contralateral reactions is related to the mechanism limiting the frequency at which binaural beats are perceived

Hippocampal representations switch from errors to predictions during acquisition of predictive associations

We constantly exploit the statistical regularities in our environment to help guide our perception. The hippocampus has been suggested to play a pivotal role in both learning environmental statistics, as well as exploiting them to generate perceptual predictions. However, it is unclear how the hippocampus balances encoding new predictive associations with the retrieval of existing ones. Here, we present the results of two high resolution human fMRI studies (N = 24 for both experiments) directly investigating this. Participants were exposed to auditory cues that predicted the identity of an upcoming visual shape (with 75% validity). Using multivoxel decoding analysis, we find that the hippocampus initially preferentially represents unexpected shapes (i.e., those that violate the cue regularities), but later switches to representing the cue-predicted shape regardless of which was actually presented. These findings demonstrate that the hippocampus is involved both acquiring and exploiting predictive associations, and is dominated by either errors or predictions depending on whether learning is ongoing or complete

Immediate access arteriovenous grafts versus tunnelled central venous catheters: study protocol for a randomised controlled trial

Background Autologous arteriovenous fistulae (AVF) are the optimal form of vascular access for haemodialysis. AVFs typically require 6 to 8 weeks to “mature” from the time of surgery before they can be cannulated. Patients with end-stage renal disease needing urgent vascular access therefore traditionally require insertion of a tunnelled central venous catheter (TCVC). TCVCs are associated with high infection rates and central venous stenosis. Early cannulation synthetic arteriovenous grafts (ecAVG) provide a novel alternative to TCVCs, permitting rapid access to the bloodstream and immediate needling for haemodialysis. Published rates of infection in small series are low. The aim of this study is to compare whether TCVC ± AVF or ecAVG ± AVF provide a better strategy for managing patients requiring immediate vascular access for haemodialysis. Methods/design This is a prospective randomised controlled trial comparing the strategy of TCVC ± AVF to ecAVG ± AVF. Patients requiring urgent vascular access will receive a study information sheet and written consent will be obtained. Patients will be randomised to receive either: (i) TCVC (and native AVF if this is anatomically possible) or (ii) ecAVG (± AVF). 118 patients will be recruited. The primary outcome is systemic bacteraemia at 6 months. Secondary outcomes include culture-proven bacteraemia rates at 1 year and 2 years; primary and secondary patency rates at 3, 6, 12 and 24 months; stenoses; re-intervention rates; re-admission rate; mortality and quality of life. Additionally, treatment delays, impact on service provision and cost-effectiveness will be evaluated. Discussion This is the first randomised controlled trial comparing TCVC to ecAVG for patients requiring urgent vascular access for haemodialysis. The complications of TCVC are considered an unfortunate necessity in patients requiring urgent haemodialysis who do not have autologous vascular access. If this study demonstrates that ecAVGs provide a safe and practical alternative to TCVC, this could instigate a paradigm shift in nephrology thinking and access planning.</p

Causal pathways of flood related river drowning deaths in Australia

Introduction: Globally, flooding is the most common of all natural disasters and drowning is the leading cause of death during floods. In Australia, rivers are the most common location of drowning and experience flooding on a regular basis. Methods: A cross-sectional, total population audit of all known unintentional river flood related fatal drownings in Australia between 1-July-2002 and 30-June-2012 was conducted to identify trends and causal factors. Results: There were 129 (16.8%) deaths involving river flooding, representing a crude drowning rate of 0.06 per 100,000 people per annum. Half (55.8%) were due to slow onset flooding, 27.1% flash flooding and the type of flooding was unknown in 17.1% of cases. Those at an increased risk were males, children, driving (non-aquatic transport) and victims who were swept away (p<0.01). When compared to drownings in major cities, people in remote and very remote locations were 79.6 and 229.1 times respectively more likely to drown in river floods. Common causal factors for falls into flooded rivers included being alone and a blood alcohol content ≥0.05% (for adults). Non-aquatic transport incident victims were commonly the drivers of four wheel drive vehicles and were alone in the car, whilst attempting to reach their own home or a friend’s. Discussion: Flood related river drownings are preventable. Strategies for prevention must target causal factors such as being alone, influence of alcohol, type/size of vehicle, and intended destination. Strategies to be explored and evaluated include effective signage, early warning systems, alternate routes and public awareness for drivers

A class of Lorentzian Kac-Moody algebras

We consider a natural generalisation of the class of hyperbolic Kac-Moody algebras. We describe in detail the conditions under which these algebras are Lorentzian. We also construct their fundamental weights, and analyse whether they possess a real principal so(1,2) subalgebra. Our class of algebras include the Lorentzian Kac-Moody algebras that have recently been proposed as symmetries of M-theory and the closed bosonic string.Comment: 40 pages TeX, 5 eps-figure

Distribution of subsequent primary invasive melanomas following a first primary invasive OR in situ Melanoma Queensland, Australia, 1982-2010

IMPORTANCE: Melanoma survivors are known to have a highly elevated risk of subsequent primary melanomas. OBJECTIVE: To determine the relative risk of subsequent primary invasive melanomas following a first primary invasive or in situ melanoma, with a focus on body site. DESIGN, SETTING, AND PARTICIPANTS: A retrospective cohort studywas conducted using population-based administrative data for melanoma diagnoses collected by the Queensland Cancer Registry, Queensland, Australia. Deidentified records of all cases of melanoma among Queensland residents during the period 1982-2005 were obtained and reviewed to December 31, 2010. There were 39 668 eligible cases of first primary invasive melanoma and 22 845 cases of first primary in situ melanoma. MAIN OUTCOMES AND MEASURES: Standardized incidence ratios (SIRs), a proxy measure for relative risk, were calculated by dividing the observed number of subsequent primary invasive melanomas by the product of the strata-specific incidence rates that occurred in the general population and the cumulative time at risk for the cohort. Synchronous subsequent melanomas (diagnosed within 60 days of the first primary melanoma) were excluded. Differences between SIRs were assessed using multivariate negative binomial regression adjusted for sex, age group, time to second diagnosis, and body site and expressed in terms of adjusted SIR ratios with corresponding 95%CIs. RESULTS: There were 5358 subsequent primary invasive melanomas diagnosed, resulting in SIRs of 5.42 (95%CI, 5.23-5.61) and 4.59 (4.37-4.82) for persons with a first primary invasive or in situ melanoma, respectively. The SIRs remained elevated throughout the follow-up period. In general, subsequent primary invasive melanomas were more likely to occur at the same body site as the initial invasive or in situ melanoma. The largest relative risk was for females with a first primary invasive melanoma on the head followed by a subsequent primary invasive melanoma also on the head (SIR, 13.32; 95%CI, 10.28-16.98). CONCLUSIONS AND RELEVANCE: Melanoma survivors require ongoing surveillance, with particular attention required for the body site of the initial lesion. Clinical practice guidelines have recognized the importance of monitoring for people with invasive melanoma; the results of the present study highlight the need for similar levels of supervision for those with a diagnosis of in situ melanoma

Public use and perceptions of emergency departments: A population survey

Objectives: To inform demand management strategies aimed at reducing congestion in EDs by: (i) identifying public use of EDs, decision-making and reasons; and (ii) measuring acceptance of alternative care models.\ud \ud Methods: A cross-sectional telephone survey of a random sample of Queensland population aged 18 years or older residing in a dwelling unit in Queensland that could be contacted on a land-based telephone service was conducted. One person per household was selected according to a predetermined algorithm to ensure sex and regional balance were interviewed. The main outcome measures were: ED use, attitudes towards ED staff and services, and alternative models of care.\ud \ud Results: The final sample included a total of 1256 respondents (response rate = 40.3%). Twenty-one per cent attended EDs in the preceding 12 months. The decision to attend was made by patients (51%), health and medical professionals (31%), and others (18%). The main reasons included perceived severity of the illness (47%), unavailability of alternative services (26%) and better care (11%). Most respondents agreed with more flexible care models of service delivery including incentives for general practitioners (90%), private health insurance coverage for ED use (89%), and enhanced roles for paramedics and nurses.\ud \ud Conclusions: Main reason for attending ED is perceived severity of illness, followed by lack of alternative care. The majority of both consumers and the public are in favour of more flexible care models. However, further research is necessary to detail those alternatives and to test and validate their effectiveness

Factors associated with spontaneous clearance of chronic hepatitis C virus infection

Background &amp; Aims: Spontaneous clearance of chronic hepatitis C virus (HCV) infection (CHC) is rare. We conducted a retrospective case-control study to identify rates and factors associated with spontaneous clearance of CHC. Methods: We defined cases as individuals who spontaneously resolved CHC, and controls as individuals who remained chronically infected. We used data obtained on HCV testing between 1994 and 2013 in the West of Scotland to infer case/control status. Specifically, untreated patients with ⩾2 sequential samples positive for HCV RNA ⩾6 months apart followed by ⩾1 negative test, and those with ⩾2 positive samples ⩾6 months apart with no subsequent negative samples were identified. Control patients were randomly selected from the second group (4/patient of interest). Case notes were reviewed and patient characteristics obtained. Results: 25,113 samples were positive for HCV RNA, relating to 10,318 patients. 50 cases of late spontaneous clearance were identified, contributing 241 person-years follow-up. 2,518 untreated, chronically infected controls were identified, contributing 13,766 person-years follow-up, from whom 200 controls were randomly selected. The incidence rate of spontaneous clearance was 0.36/100 person-years follow-up, occurring after a median 50 months’ infection. Spontaneous clearance was positively associated with female gender, younger age at infection, lower HCV RNA load and co-infection with hepatitis B virus. It was negatively associated with current intravenous drug use. Conclusions: Spontaneous clearance of CHC occurs infrequently but is associated with identifiable host and viral factors. More frequent HCV RNA monitoring may be appropriate in selected patient groups. Lay summary: Clearance of hepatitis C virus infection without treatment occurs rarely once chronic infection has been established. We interrogated a large Scottish patient cohort and found that it was more common in females, patients infected at a younger age or with lower levels of HCV in the blood, and patients co-infected with hepatitis B virus. Patients who injected drugs were less likely to spontaneously clear chronic infection

Student perspectives of preparedness characteristics for clinical learning within a fully distributed veterinary teaching model.

The transition into the clinical environment is challenging and associated with significant stress and anxiety. This study aimed to examine the perspectives of students on the characteristics important for preparedness for clinical learning and the influence of gender, age, and graduate status on those perspectives. This descriptive, questionnaire-based study of 62 characteristics categorised into six themes was conducted within the Surrey School of Veterinary Medicine completed by 139 students commencing their final clinical year. The Friedman test and post-hoc Wilcoxon signed rank sum test explored for differences in ranking across the themes. Ordinal logistic regression and Mann-Whitney U pairwise comparisons were utilised to investigate for effects of gender, age, and graduate status on theme ranking. There was a significant difference (P 0.05) of gender, age or graduate status on student rating of preparedness characteristics. Integrating learning opportunities of those preparedness characteristics in the pre-clinical curriculum may improve students' preparedness for the clinical environment