Why do paramedics choose to bring patients to a private emergency department?

OBJECTIVE: While prior experience, favourable location and anticipation of high quality care are known to influence patient choice to attend a private ED, it is likely that decision-making is also influenced by other persons. In particular, patients arriving by ambulance are under the care of paramedics, whose values towards healthcare and rationale for choosing one ED over another have not been studied. This study aimed to describe reasons why paramedics choose to bring patients to a private ED. METHODS: Exploratory, qualitative study using semi-structured, face-to-face interviews with paramedics bringing patients to a private ED from the community. Two primary questions reinforced by structured prompts were asked: 'Why did you choose to come to this emergency department?' and 'What are your general expectations of this emergency department visit?' Interviews were audio recorded, transcribed verbatim and analysed thematically. RESULTS: Fifty paramedics were interviewed with 48 interviews able to be transcribed and used in analysis. Four factors were identified to increase the likelihood of a private ED destination: specific direction, institutional allegiance, hospital logistics and systems and receiving hospital service ethos. CONCLUSIONS: Paramedics take into consideration when possible patient's wishes and are more likely to bring a patient to a private ED if they have specific direction from the patient or the patient's family or GP. The likelihood of presenting to a private ED is increased if the patient has an allegiance with the facility and the paramedics perceive favourably the hospital logistics and systems as well as service ethos.

Emergency department 'undercrowding' is associated with decreased waiting times.

OBJECTIVE: To evaluate the effect of a sudden and sustained decrease in patient presentations on waiting times and other measures of workload and flow following the opening of a large, greenfields ED adjacent to our own. METHOD: A descriptive study involving all patients presenting to a private urban district hospital ED for two 60 day periods, immediately before and after the opening of the tertiary hospital ED. Changes in median waiting time, case-mix distribution, method of arrival, total admissions and total waiting time were compared pre-opening and post-opening. Non-normally distributed variables were analysed using Mann-Whitney U-tests. Categorical variables were compared using χ(2) analyses. RESULTS: Patient presentations decreased by 28% with a parallel decline in median waiting time of 15 min (from 26 to 11 min) (P < 0.001). Total waiting time was approximately 29 h less per day in the post-opening period. Patient urgency by triage category did not change significantly (P = 0.316), whereas the proportion of presentations by ambulance decreased 15.9% (P = 0.048) and admission rate increased from 29.1% to 32.6% (P = 0.002). CONCLUSIONS: Patient presentation numbers are strongly associated with and likely impact on median waiting time. Understanding that controlling demand can lead to significant benefits in patient processing, flow and overall patient perceived level of care and satisfaction is relevant to any discussion on ED overcrowding and the deleterious effects of access block.

Why do patients choose to attend a private emergency department?

OBJECTIVE: Understanding the reasons patients decide to attend a particular acute care service, and their expectations of that service, is important in providing optimal patient care. The present study aimed to determine factors influencing patient decisions to attend a private Australian ED, an issue that has not been previously addressed in the literature. METHODS: Semi-structured face-to-face interviews with ED patients, purposively sampled to broadly reflect the departmental caseload and casemix. The two primary questions asked were: 'Why did you choose to come to this emergency department?' and 'What are your general expectations of this emergency department visit?'. Interviews were audio recorded, transcribed verbatim, and then analysed using manifest and then latent content analysis techniques. RESULTS: All patients approached (n = 30) agreed to interview. Four key themes were identified: prior experience of the hospital, convenient location of the hospital, anticipated high-quality care and anticipated short wait times. CONCLUSIONS: Patients chose to use the private ED because of prior experience, proximity, and an expectation they would be seen promptly and be provided with competent care.

Volitional control of neural activity relies on the natural motor repertoire.

BACKGROUND: The results from recent brain-machine interface (BMI) studies suggest that it may be more efficient to use simple arbitrary relationships between individual neuron activity and BMI movements than the complex relationship observed between neuron activity and natural movements. This idea is based on the assumption that individual neurons can be conditioned independently regardless of their natural movement association. RESULTS: We tested this assumption in the parietal reach region (PRR), an important candidate area for BMIs in which neurons encode the target location for reaching movements. Monkeys could learn to elicit arbitrarily assigned activity patterns, but the seemingly arbitrary patterns always belonged to the response set for natural reaching movements. Moreover, neurons that are free from conditioning showed correlated responses with the conditioned neurons as if they encoded common reach targets. Thus, learning was accomplished by finding reach targets (intrinsic variable of PRR neurons) for which the natural response of reach planning could approximate the arbitrary patterns. CONCLUSIONS: Our results suggest that animals learn to volitionally control single-neuron activity in PRR by preferentially exploring and exploiting their natural movement repertoire. Thus, for optimal performance, BMIs utilizing neural signals in PRR should harness, not disregard, the activity patterns in the natural sensorimotor repertoire.

Blood cultures ordered in the adult emergency department are rarely useful.

OBJECTIVES: Although blood cultures are commonly ordered in the emergency department, there is controversy about their utility. This study aimed to determine the usefulness of blood cultures in the management of patients presenting to a tertiary adult teaching hospital emergency department in Perth, Western Australia. METHODS: A detailed chart review was undertaken of all blood cultures taken in our emergency department over a 2-month period. All patients within the hospital having blood cultures taken were identified; from this group, blood cultures originating from the emergency department were reviewed. Data were collected concerning patient demographics, culture indication, vital signs, culture outcome, disposition and alterations in management resulting from the blood culture. RESULTS: 218 blood cultures were ordered from the emergency department during the study period. This represented 4.0% (218/5478) of the total number of patients seen. Of the 218 cultures, only 30 were positive (13% of the study population), with 16 (7.3%) probable contaminants and 14 (6.4 %) true positives. No anaerobic isolates were identified. Of the 14 significantly positive blood cultures, the result influenced management in six patients, resulting in a useful culture rate of 2.8% (6/218). CONCLUSION: Blood cultures are ordered on a significant number of patients seen in the emergency department but rarely alter management. Our findings in conjunction with other studies suggest that eliminating blood cultures in immunocompetent patients with common illnesses such as urinary tract infection, community acquired pneumonia and cellulitis, may significantly reduce the number of blood cultures, producing substantial savings without jeopardizing patient care. This needs prospective study and validation.

A functional comparison of the venom of three Australian jellyfish--Chironex fleckeri, Chiropsalmus sp., and Carybdea xaymacana--on cytosolic Ca2+, haemolysis and Artemia sp. lethality.

Cnidarian venoms produce a wide spectrum of envenoming syndromes in humans ranging from minor local irritation to death. Here, the effects of Chironex fleckeri, Chiropsalmus sp., and Carybdea xaymacana venoms on ventricular myocyte cytosolic Ca2+, haemolysis and Artemia sp. lethality are compared for the first time. All three venoms caused a large, irreversible elevation of cytosolic Ca2+ in myocytes as measured using the Ca2+ sensitive fluorescent probe Indo-1. The L-type Ca2+ channel antagonist verapamil had no effect on Ca2+ influx whilst La3+, a non-specific channel and pore blocker, inhibited the effect. Haemolytic activity was observed for all venoms, with C. xaymacana venom displaying the greatest activity. These activities are consistent with the presence of a pore-forming toxin existing in the venoms which has been demonstrated by transmission electron microscopy in the case of C. fleckeri. The venom of C. fleckeri was found to be more lethal against Artemia sp. than the venom of the other species, consistent with the order of known human toxicities. This suggests that the observed lytic effects may not underlie the lethal effects of the venom, and raises the question of how such potent activities are dealt with by envenomed humans.

Comprehensive analysis of human immunodeficiency virus type 1-specific CD4 responses reveals marked immunodominance of gag and nef and the presence of broadly recognized peptides.

Increasing evidence suggests that human immunodeficiency virus type 1 (HIV-1)-specific CD4 T-cell responses contribute to effective immune control of HIV-1 infection. However, the breadths and specificities of these responses have not been defined. We screened fresh CD8-depleted peripheral blood mononuclear cells (PBMC) from 36 subjects at different stages of HIV-1 infection for virus-specific CD4 responses by gamma interferon enzyme-linked immunospot assay, using 410 overlapping peptides spanning all HIV-1 proteins (based on the clade B consensus sequence). HIV-1-specific CD4 responses were identified in 30 of the 36 individuals studied, with the strongest and broadest responses detected in persons treated in acute infection who underwent treatment interruption. In individuals with identified responses, the total number of recognized HIV-1 peptides ranged from 1 to 36 (median, 7) and the total magnitude of responses ranged from 80 to >14,600 (median, 990) spot-forming cells/10(6) CD8-depleted PBMC. Neither the total magnitude nor the number of responses correlated with viremia. The most frequent and robust responses were directed against epitopes within the Gag and Nef proteins. Peptides targeted by >/=25% of individuals were then tested for binding to a panel of common HLA-DR molecules. All bound broadly to at least four of the eight alleles tested, and two bound to all of the HLA-DR molecules studied. Fine mapping and HLA restriction of the responses against four of these peptides showed a combination of clustering of epitopes and promiscuous presentation of the same epitopes by different HLA class II alleles. These findings have implications for the design of immunotherapeutic strategies and for testing candidate HIV vaccines.

Mutually antagonistic effects of androgen and activin in the regulation of prostate cancer cell growth.

Activin, a member of the TGFbeta superfamily, is expressed in the prostate and inhibits growth. We demonstrate that the effects of activin and androgen on regulation of prostate cancer cell growth are mutually antagonistic. In the absence of androgen, activin induced apoptosis in the androgen-dependent human prostate cancer cell line LNCaP, an effect suppressed by androgen administration. Although activin by itself did not alter the cell cycle distribution, it potently suppressed androgen- induced progression of cells into S-phase of the cell cycle and thus inhibited androgen-stimulated growth of LNCaP cells. Expression changes in cell cycle regulatory proteins such as Rb, E2F-1, and p27 demonstrated a strong correlation with the mutually antagonistic growth regulatory effects of activin and androgen. The inhibitory effect of activin on growth was independent of serine, serine, valine, serine motif phosphorylation of Smad3. Despite their antagonistic effect on growth, activin and androgen costimulated the expression of prostate-specific antigen through a Smad3-mediated mechanism. These observations indicate the existence of a complex cross talk between activin and androgen signaling in regulation of gene expression and growth of the prostate.

Jellyfish envenoming syndromes: unknown toxic mechanisms and unproven therapies.

Interest in envenoming syndromes caused by Australian jellyfish has been intense since the deaths in early 2002 of two tourists in Queensland, attributed to the Irukandji syndrome. We review current knowledge of these envenoming syndromes, mechanisms of venom action and therapy, focusing on the deadly box jellyfish, Chironex fleckeri, and the array of jellyfish thought to cause the Irukandji syndrome. Current understanding of jellyfish venom activity is very limited, and many treatments are unproven and based on anecdote.