Recorded infection control messages delay inter-professional communication but are not associated with COVID-19 prevalence or mortality: insights from a national switchboard analysis.

Appropriate dissemination of information to the general public is a key component of the pandemic response. In 2018, recorded infection control advice messages were affixed to 30% of England's automated hospital switchboards during the seasonal influenza and norovirus outbreaks. As the majority of messages were mandatory for all callers, healthcare professionals using the hospital switchboard - including during time-critical emergencies - had their enquiries significantly delayed by these measures. Importantly, published analyses did not demonstrate an association between these messages and patient outcomes. As of May 2020, 85% of NHS trusts made use of infection control messages; on average, these delayed healthcare professionals by 59.4 seconds per call, but had no clear association with patient outcomes from COVID-19. An ongoing national switchboard quality improvement project seeks to establish a gold standard whereby healthcare professionals with urgent enquiries can press 'X' to skip past infection control messages and have their calls triaged immediately.

Reproducible 3D printed head tanks for electrical impedance tomography with realistic shape and conductivity distribution.

OBJECTIVE: Electrical impedance tomography (EIT) has many promising applications in brain injury monitoring. To evaluate both instrumentation and reconstruction algorithms, experiments are first performed in head tanks. Existing methods, whilst accurate, produce a discontinuous conductivity, and are often made by hand, making it hard for other researchers to replicate. APPROACH: We have developed a method for constructing head tanks directly in a 3D printer. Conductivity was controlled through perforations in the skull surface, which allow for saline to pass through. Varying the diameter of the holes allowed for the conductivity to be controlled with 3% error for the target conductivity range. Taking CT and MRI segmentations as a basis, this method was employed to create an adult tank with a continuous conductivity distribution, and a neonatal tank with fontanelles. MAIN RESULTS: Using 3D scanning a geometric accuracy of 0.21 mm was recorded, equal to that of the precision of the 3D printer used. Differences of 6.1% ± 6.4% (n = 11 in 4 tanks) compared to simulations were recorded in c. 800 boundary voltages. This may be attributed to the morphology of the skulls increasing tortuosity effects and hole misalignment. Despite significant differences in errors between three repetitions of the neonatal tank, images of a realistic perturbation could still be reconstructed with different tanks used for the baseline and perturbation datasets. SIGNIFICANCE: These phantoms can be reproduced by any researcher with access to a 'hobbyist' 3D printer in a matter of days. All design files have been released using an open source license to encourage reproduction and modification.