Implementation study reporting diagnostic accuracy, outcomes and costs in a multicentre randomised controlled trial of non-expert lung ultrasound to detect pulmonary oedema.

BACKGROUND: Lung ultrasound experts claim that 'B line' artefacts herald pulmonary oedema, but links between early recognition and improved outcome are unconfirmed, particularly for non-expert clinicians. OBJECTIVE: Assess individual and system impacts of early, non-expert lung ultrasound (LUS) in breathless older patients. METHODS: Prospective single-blinded randomised controlled trial of point of care LUS by non-expert clinicians, augmenting ED assessment of patients over 60 years, presenting with dyspnoea. After brief training, clinicians at three hospitals used computer-generated block randomisation envelopes to allocate a convenience sample of consenting presenters to conventional or LUS-augmented management. ED provisional diagnosis was compared to a post-discharge chart audit diagnosis, blinded to ultrasound findings. Secondary outcomes were the length of stay in ED and hospital, costs and discharge destinations. RESULTS: From three sites, 224 controls were compared with 218 interventions. LUS improved diagnostic accuracy, with a small effect size in favour of LUS (risk difference: 6.5%, 95% CI 0.9-12) and a number needed to scan of 16 (95% CI 8-107). With LUS, ED and hospital stay increased non-significantly, while discharge destination trends improved. No harm ensued. CONCLUSIONS: Non-expert LUS augmenting dyspnoea workup may improve diagnostic accuracy, but did not significantly alter costs or outcomes in the ED or the hospital. TRIAL REGISTRATION: Australia and New Zealand Clinical Trials Registry (ACTRN12613001023741).

Accelerated Variational Quantum Eigensolver.

The problem of finding the ground state energy of a Hamiltonian using a quantum computer is currently solved using either the quantum phase estimation (QPE) or variational quantum eigensolver (VQE) algorithms. For precision ε, QPE requires O(1) repetitions of circuits with depth O(1/ε), whereas each expectation estimation subroutine within VQE requires O(1/ε^{2}) samples from circuits with depth O(1). We propose a generalized VQE algorithm that interpolates between these two regimes via a free parameter α∈[0,1], which can exploit quantum coherence over a circuit depth of O(1/ε^{α}) to reduce the number of samples to O(1/ε^{2(1-α)}). Along the way, we give a new routine for expectation estimation under limited quantum resources that is of independent interest.

Nonclassicality of Temporal Correlations.

The results of spacelike separated measurements are independent of distant measurement settings, a property one might call two-way no-signaling. In contrast, timelike separated measurements are only one-way no-signaling since the past is independent of the future but not vice versa. For this reason some temporal correlations that are formally identical to nonclassical spatial correlations can still be modeled classically. We propose a new formulation of Bell's theorem for temporal correlations; namely, we define nonclassical temporal correlations as the ones which cannot be simulated by propagating in time the classical information content of a quantum system given by the Holevo bound. We first show that temporal correlations between results of any projective quantum measurements on a qubit can be simulated classically. Then we present a sequence of general measurements on a single m-level quantum system that cannot be explained by propagating in time an m-level classical system and using classical computers with unlimited memory.

Sensitivity, specificity and diagnostic accuracy of novices integrating lung ultrasound into the care of breathless older patients.

Background: Lung ultrasound is frequently used to identify pulmonary oedema, using the 'B line' artefact. A small study in 2011 suggested that novice sonologists had a potential diagnostic accuracy of 85%, when performing the test without reference to other patient information. Aim: We aimed to test the overall diagnostic accuracy of novice clinician sonologists incorporating the 2011 protocol into routine assessment of the patient. Method: A prospective convenience sample of breathless older patients presenting to ED received an 8-view lung scan early in management. Initial ED diagnoses, utilising all information including ultrasound result, were compared against the opinion of a medical expert auditing the patient records after discharge from hospital. Results: The cohort of five novices scanned 63 cases, from which eleven were excluded. Novices using ultrasound differentiated between pulmonary oedema and other causes of breathlessness with a sensitivity of 71% (95%CI 44 to 87), Specificity of 91% (76 to 98), a diagnostic accuracy of 85% (72 to 92), a positive LR of 8.2 (2.7 to 25) and a negative LR of 0.32 (0.15 to 0.68). Discussion: The diagnostic accuracy of emergency department clinicians incorporating novice lung ultrasound into the investigation of breathlessness is consistent with the diagnostic accuracy of scanning performed in parallel to patient care, and is likely to be an improvement on current estimates of conventional ED diagnostic strategies. Clinicians should not be afraid that their learning curve would disadvantage the patient.

Effecting change using careplans: experience from two fractured neck of femur pathways.

OBJECTIVE: To use a qualitative track of the effects of two fractured neck of femur careplans (1 & 2) implemented at the Ipswich Emergency Department in 2002 and 2003 in order to comment on the reasons for comparative successes and failures as instruments for change in clinical practice. Careplan 1 was initiated by local clinicians in 2002, rescinded in 2003 to make way for the system wide careplan 2, then informally restituted in 2004 after careplan 2 was withdrawn. Careplan 2 did not articulate specific ED management plans. METHOD: Biennial retrospective chart audits of two newly introduced evidence-based clinical practices over time was used to track changes from careplan 1. These were the use of regional anaesthesia by medical staff, and the compliance with indwelling urinary catheter insertion by nursing staff. RESULTS: Elements of careplan 1 continued despite lack of promotion. There has been significant increase in nerve block (2.8% to 27%) and indwelling catheter insertion (26% to 75%) from 2000 to 2009. Formal use of careplan 1 has declined to 13-20% in 2009. Careplan 2 was withdrawn for review in 2004. CONCLUSIONS: Careplans are one way to effect lasting changes in clinical behaviours which may persist beyond their implementation and promotion phases. For acceptance, corporate plans should incorporate local practices. For longevity, local plans should comply with the corporate vision of continuity of care, but local investment in the plan will facilitate uptake.

Retrospective case note review of patients brought to Ipswich emergency department under mental health emergency examination orders: does intoxication alter outcome?

OBJECTIVE: To alter staff perceptions, and to examine alternative management processes for intoxicated patients brought to Ipswich ED under mental health emergency examination orders by comparing disposition outcomes with non-intoxicated patients. METHODS: Consultation-Liaison mental health nursing staff completed surveys on all patients assessed under emergency examination orders over a 6 month period in 2008. Patients were classified as intoxicated if they recorded alcometer readings of greater than 0.05%, or self-reported drug use during the events leading to their transport to the ED. Outcomes were retrospectively collated with entries in Clinical Liaison nursing logbooks. Outcome measures recorded were rates of admission, outpatient referrals to the Integrated Mental Health Service, follow up by other community services or no follow up. Differences in outcomes for intoxicated and non-intoxicated patient groups were tested for significance using χ(2) or Fisher's exact test. RESULTS: One hundred and sixty-eight cases were included in the audit. No cases were excluded. Sixty patients were identified as intoxicated. The age and sex distributions were similar between intoxicated and non-intoxicated patients. There were no significant differences in admission or referral rates. The average length of assessment time in the ED was longer in the intoxicated group. DISCUSSION: This audit showed similar outcomes for both patient groups contrary to the perceptions expressed by ED staff in informal surveys. The admission and referral rate for both groups indicate they are an at-risk population. The admission rate of 16% has led to this department negotiating alternative accommodation for patients while they sober up.