Population screening for colorectal cancer: the implications of an ageing population

Population screening for colorectal cancer (CRC) has recently commenced in the United Kingdom supported by the evidence of a number of randomised trials and pilot studies. Certain factors are known to influence screening cost-effectiveness (e.g. compliance), but it remains unclear whether an ageing population (i.e. demographic change) might also have an effect. The aim of this study was to simulate a population-based screening setting using a Markov model and assess the effect of increasing life expectancy on CRC screening cost-effectiveness. A Markov model was constructed that aimed, using a cohort simulation, to estimate the cost-effectiveness of CRC screening in an England and Wales population for two timescales: 2003 (early cohort) and 2033 (late cohort). Four model outcomes were calculated; screened and non-screened cohorts in 2003 and 2033. The screened cohort of men and women aged 60 years were offered biennial unhydrated faecal occult blood testing until the age of 69 years. Life expectancy was assumed to increase by 2.5 years per decade. There were 407 552 fewer people entering the model in the 2033 model due to a lower birth cohort, and population screening saw 30 345 fewer CRC-related deaths over the 50 years of the model. Screening the 2033 cohort cost £96 million with cost savings of £43 million in terms of detection and treatment and £28 million in palliative care costs. After 30 years of follow-up, the cost per life year saved was £1544. An identical screening programme in an early cohort (2003) saw a cost per life year saved of £1651. Population screening for CRC is costly but enables cost savings in certain areas and a considerable reduction in mortality from CRC. This Markov simulation suggests that the cost-effectiveness of population screening for CRC in the United Kingdom may actually be improved by rising life expectancies

Investigation of the Thermal Performance of Salt Hydrate Phase Change of Nanoparticle Slurry Flow in a Microchannel

Computational study was conducted to investigate the thermal performance of water-based salt hydrate S44 nanoparticles as the phase change material (PCM) in a microchannel heat sink. Constant heat dissipation was applied on the top wall of the heat sink. Forced internal convection of the PCM slurry flow was performed through a homogeneous approach. Three thermal performance parameters, including effectiveness ratio, performance index, and Merit number, were used to quantify the cooling performance of S44 for various concentrations of the PCM nanoparticles. The thermal performance of the salt hydrate S44 slurry was also compared with a similar study conducted for lauric acid nanoparticle slurry found in the literature. Specific operating conditions were identified. The salt hydrate S44 would provide better thermal performance than lauric acid, and vice versa. Finally, Nusselt number correlations have been developed for the microchannel PCM heat sink for Reynolds numbers in the range 12.23 to 47.14 and Prandtl numbers in the range 3.74 to 5.30. A design guideline for manufacturing PCM particles and microchannel heat sinks is provided. With this guideline, the heat absorption ability of the heat sink is maximized, and the pumping power and the losses related to the addition of the particles are minimized

Outcomes after perioperative SARS-CoV-2 infection in patients with proximal femoral fractures: an international cohort study

Objectives Studies have demonstrated high rates of mortality in people with proximal femoral fracture and SARS-CoV-2, but there is limited published data on the factors that influence mortality for clinicians to make informed treatment decisions. This study aims to report the 30-day mortality associated with perioperative infection of patients undergoing surgery for proximal femoral fractures and to examine the factors that influence mortality in a multivariate analysis. Setting Prospective, international, multicentre, observational cohort study. Participants Patients undergoing any operation for a proximal femoral fracture from 1 February to 30 April 2020 and with perioperative SARS-CoV-2 infection (either 7 days prior or 30-day postoperative). Primary outcome 30-day mortality. Multivariate modelling was performed to identify factors associated with 30-day mortality. Results This study reports included 1063 patients from 174 hospitals in 19 countries. Overall 30-day mortality was 29.4% (313/1063). In an adjusted model, 30-day mortality was associated with male gender (OR 2.29, 95% CI 1.68 to 3.13, p80 years (OR 1.60, 95% CI 1.1 to 2.31, p=0.013), preoperative diagnosis of dementia (OR 1.57, 95% CI 1.15 to 2.16, p=0.005), kidney disease (OR 1.73, 95% CI 1.18 to 2.55, p=0.005) and congestive heart failure (OR 1.62, 95% CI 1.06 to 2.48, p=0.025). Mortality at 30 days was lower in patients with a preoperative diagnosis of SARS-CoV-2 (OR 0.6, 95% CI 0.6 (0.42 to 0.85), p=0.004). There was no difference in mortality in patients with an increase to delay in surgery (p=0.220) or type of anaesthetic given (p=0.787). Conclusions Patients undergoing surgery for a proximal femoral fracture with a perioperative infection of SARS-CoV-2 have a high rate of mortality. This study would support the need for providing these patients with individualised medical and anaesthetic care, including medical optimisation before theatre. Careful preoperative counselling is needed for those with a proximal femoral fracture and SARS-CoV-2, especially those in the highest risk groups. Trial registration number NCT0432364